Repair of umbilical hernias concomitant to other procedures is safe: a propensity score-matched database study

BACKGROUND

Repair of an umbilical hernia is most often considered the less important condition when concomitant with other abdominal surgery. Despite this, the evidence for a concomitant umbilical hernia repair is sparse. The aim of this nationwide cohort study is to compare the short- and long-term outcomes of primary umbilical hernia repair and umbilical hernia repair concomitant with other abdominal surgery.

METHOD

Data from the Danish Hernia Database and the National Patients Registry from January 2007 to December 2018 was merged, resulting in identification of patients receiving umbilical hernia concomitant to another abdominal surgery (laparoscopic inguinal hernia repair, laparoscopic cholecystectomy, and laparoscopic appendectomy). This group was propensity score matched with patients undergoing umbilical hernia repair as a primary procedure. Outcome data included 90-day readmission, 90-day reoperation, and operation for recurrence.

RESULTS

A total of 3365 primary umbilical hernia repairs and 2418 umbilical hernia repairs concomitant to other abdominal surgery were included. Readmission (10.5%, 255/2418) and reoperation (3.8%, 93/2418) rates within 90 days were decreased for umbilical hernia repairs concomitant to other abdominal surgery, compared with primary umbilical hernia repairs (22.7%, 765/3365) and (10.5%, 255/3365), P < 0.001 and P < 0.001, respectively. The rate of operation for recurrence was significantly increased for primary repairs (4.2%, 141/3365), compared with repairs concomitant to other abdominal surgery (3.2%, 77/2418), P = 0.014.

CONCLUSION

Outcome in umbilical hernia repair performed concomitant to laparoscopic inguinal hernia repair, elective or emergency laparoscopic cholecystectomy, or laparoscopic appendectomy is comparable to umbilical hernia repair without concomitant surgery.

Time to pregnancy and life expectancy: a cohort study of 18 796 pregnant couples

STUDY QUESTION

Is fecundity, measured as time to pregnancy (TTP), associated with mortality in parents?

SUMMARY ANSWER

Prolonged TTP is associated with increased mortality in both mothers and fathers in a dose-response manner.

WHAT IS KNOWN ALREADY

Several studies have linked both male and female fecundity to mortality. In women, infertility has been linked to several diseases, but studies suggest that the underlying conditions, rather than infertility, increase mortality.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study was carried out on 18 796 pregnant couples, in which the pregnant women attended prophylactic antenatal care between 1973 and 1987 at a primary and tertiary care unit. The couples were followed in Danish mortality registers from their child's birth date until death or until 2018. The follow-up period was up to 47 years, and there was complete follow-up until death, emigration or end of study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

At the first antenatal visit, the pregnant women were asked to report the time to the current pregnancy. Inclusion was restricted to the first pregnancy, and TTP was categorised into <12 months, ≥12 months, not planned, and not available. In sub-analyses, TTP ≥12 was further categorized into 12-35, 36-60, and >60 months. Information for parents was linked to several Danish nationwide health registries. Survival analysis was used to estimate the hazard ratios (HRs) with a 95% CI for survival and adjusted for age at the first attempt to become pregnant, year of birth, socioeconomic status, mother's smoking during pregnancy, and mother's BMI.

MAIN RESULTS AND THE ROLE OF CHANCE

Mothers and fathers with TTP >60 months survived, respectively, 3.5 (95% CI: 2.6-4.3) and 2.7 (95% CI: 1.8-3.7) years shorter than parents with a TTP <12 months. The mortality was higher for fathers (HR: 1.21, 95% CI: 1.09-1.34) and mothers (HR: 1.29, 95% CI: 1.12-1.49) with TTP ≥12 months compared to parents with TTP <12 months. The risk of all-cause mortality during the study period increased in a dose-response manner with the highest adjusted HR of 1.98 (95% CI: 1.62-2.41) for fathers and 2.03 (95% CI: 1.56-2.63) for mothers with TTP >60 months. Prolonged TTP was associated with several different causes of death in both fathers and mothers, indicating that the underlying causes of the relation between fecundity and survival may be multi-factorial.

LIMITATIONS, REASONS FOR CAUTION

A limitation is that fecundity is measured using a pregnancy-based approach. Thus, the cohort is conditioned on fertility success and excludes sterile couples, unsuccessful attempts and spontaneous abortions. The question used to measure TTP when the pregnant woman was interviewed at her first attended prophylactic antenatal care: 'From the time you wanted a pregnancy until it occurred, how much time passed?' could potentially have led to serious misclassification if the woman did not answer on time starting unprotected intercourse but on the start of wishing to have a child.

WIDER IMPLICATIONS OF THE FINDINGS

We found that TTP is a strong marker of survival, contributing to the still-emerging evidence that fecundity in men and women reflects their health and survival potential.

STUDY FUNDING/COMPETING INTEREST(S)

The authors acknowledge an unrestricted grant from Ferring. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication. M.L.E. is an advisor to Ro, VSeat, Doveras, and Next.

TRIAL REGISTRATION NUMBER

N/A.

Higher free testosterone in the third trimester was associated with lower abdominal circumference at birth in boys: Odense child cohort

OBJECTIVE

To investigate associations between maternal testosterone status and offspring birth anthropometrics.

DESIGN

Population-based prospective cohort study.

SETTING

University Hospital.

POPULATION

1486 mother-child dyads from Odense Child Cohort.

METHODS

Maternal blood samples were collected at gestational weeks 27-30 and free testosterone (FT) levels were calculated using the Vermeulen equation from total testosterone (TT) analysed by mass spectrometry and sex hormone binding globulin. Associations between FT or TT levels and birth anthropometrics were analysed with multiple linear regression models according to offspring sex with adjustment for maternal age, parity, smoking and educational level. Analyses were repeated with polycystic ovary syndrome as exposure for offspring birth anthropometrics.

MAIN OUTCOME MEASURES

Offspring birth weight (BW), birth length, abdominal and head circumferences.

RESULTS

Maternal mean (SD) age was 30.2 (4.5) years and pre-pregnancy body mass index was 23.5 (5.3) kg/m2 . In boys (n = 787), higher FT was associated with lower birth weight (adjusted doubling constant = -65.53, P = 0.010), shorter birth length (adjusted doubling constant = -0.43, P < 0.001), and lower abdominal circumference (adjusted doubling constant = -0.39, P < 0.001); Higher TT was associated with lower abdominal circumference (adjusted doubling constant = -0.25, P = 0.028). In girls, no associations were found between maternal FT or TT and offspring anthropometrics.

CONCLUSIONS

Higher maternal free testosterone exposure was linked to reduced birth weight, length and abdominal circumference in boys, whereas girls were not susceptible to maternal testosterone exposure.

Real-world accuracy of computed tomography in patients admitted with small bowel obstruction: a multicentre prospective cohort study

PURPOSE

Small bowel obstruction (SBO) is a common surgical emergency. Previous studies have shown the value computed tomography (CT) scanning in both confirming this diagnosis and identifying indications for urgent surgical intervention, such as strangulated bowel or closed loop obstructions. However, most of the literature is based on retrospective expert review of previous imaging and little data regarding the real-time accuracy of CT reporting is available. Here, we investigated the real-world accuracy of CT reporting in patients admitted with SBO.

METHODS

This was a multicentre prospective study including consecutive patients admitted with SBO. The primary outcomes were the sensitivity and specificity of CT scanning for bowel obstruction with ischaemia and closed loop obstruction. Data were retrieved from the original CT reports written by on-call radiologists and compared with operative findings.

RESULTS

One hundred seventy-six patients were included, all of whom underwent CT scanning with intravenous contrast followed by operative management of SBO. Bowel obstruction with ischaemia was noted in 20 patients, with a sensitivity and specificity of CT scanning of 40.0% and 85.5%, respectively. Closed loop obstructions were noted in 26 patients, with a sensitivity and specificity of CT scanning of 23.1% and 98.0%, respectively.

CONCLUSIONS

The real-world accuracy of CT scanning appears to be lower than previously reported in the literature. Strategies to address this could include the development of standardised reporting schemas and to increase the surgeon's own familiarity with relevant CT features in patients admitted with SBO.

Prenatal paraben exposures and birth size: Sex-specific associations in a healthy population - A study from the Odense Child Cohort

OBJECTIVES

To investigate the sex-specific associations between maternal paraben concentrations in second trimester urine and birth size of the offspring.

METHODS

A prospective cohort study of 529 mother-child pairs within the Odense Child Cohort. Pregnant women were recruited to the cohort from 2010 to 2012 and provided fasting spot urine samples in second trimester (median 28.7 weeks). Concentrations of methylparaben (MeP), ethylparaben (EtP), iso-propylparaben (i-PrP), n-propylparaben (n-PrP), n-butylparaben (n-BuP) and benzylparaben (BzP) were analyzed by isotope diluted liquid-chromatography tandem-mass-spectrometry and osmolality adjusted. Exposures were categorized into tertiles or above/below level of detection. Data on maternal and birth characteristics were extracted from hospital records. Sex-stratified multiple linear regression analyses were performed according to relevant birth outcomes (length, weight, head/abdominal circumference) adjusting for a priori defined confounders.

RESULTS

Higher paraben levels were detected in pregnant women who were older, more obese, who smoked and were primigravidae. Generally, higher maternal paraben exposure was consistently associated with lower birth size in female but not in male offspring, but with few substantial or statistically significant. Higher maternal exposure to n-BuP during pregnancy was associated with a statistically significant lower birth size in female offspring only [birth weight: -137 g (95 % CI -256; -19), head circumference: -0.48 cm (95 % CI -0.90; -0.05), abdominal circumference: -0.65 cm (95 % CI -1.21; -0.08)]. No differences in birth size were observed for other parabens.

CONCLUSION

Higher maternal exposure to n-butylparaben was associated with lower birth size in female but not male offspring.

Higher Maternal Cortisol Associated With Lower Blood Pressure in Offspring From 3 Months to 5 Years of Age in the Odense Child Cohort

BACKGROUND

Synthetic glucocorticoid exposure in late pregnancy may be associated with higher blood pressure in offspring. We hypothesized that endogenous cortisol in pregnancy relates to offspring blood pressure (OBP).

OBJECTIVE

To investigate associations between maternal cortisol status in third trimester pregnancy and OBP.

METHODS

We included 1317 mother-child pairs from Odense Child Cohort, an observational prospective cohort. Serum (s-) cortisol and 24-hour urine (u-) cortisol and cortisone were assessed in gestational week 28. Offspring systolic blood pressure and diastolic blood pressure were measured at age 3, 18 months, and 3 and 5 years. Associations between maternal cortisol and OBP were examined by mixed effects linear models.

RESULTS

All significant associations between maternal cortisol and OBP were negative. In boys in pooled analyses, 1 nmol/L increase in maternal s-cortisol was associated with average decrease in systolic blood pressure (β=-0.003 mmHg [95% CI, -0.005 to -0.0003]) and diastolic blood pressure (β=-0.002 mmHg [95% CI, -0.004 to -0.0004]) after adjusting for confounders. At 3 months of age, higher maternal s-cortisol was significantly associated with lower systolic blood pressure (β=-0.01 mmHg [95% CI, -0.01 to -0.004]) and diastolic blood pressure (β=-0.010 mmHg [95% CI, -0.012 to -0.011]) in boys after adjusting for confounders, which remained significant after adjusting for potential intermediate factors.

CONCLUSIONS

We found temporal sex dimorphic negative associations between maternal s-cortisol levels and OBP, with significant findings in boys. We conclude that physiological maternal cortisol is not a risk factor for higher blood pressure in offspring up to 5 years of age.

Self-Reported Asthma Is Associated with Reduced Sperm Count-A Cross-Sectional Study of More than 6000 Young Men from the General Population

Asthma is driven by an inflammatory response that may impact testicular function. In this cross-sectional study, we investigated the association between self-reported asthma and testicular function (semen parameters, reproductive hormone levels), and determined whether potential further inflammation due to self-reported allergy modified this association. A total of 6177 men from the general population completed a questionnaire including information on doctor-diagnosed asthma or allergy, had a physical examination, delivered a semen sample, and had a blood sample drawn. Multiple linear regression analyses were performed. A total of 656 (10.6%) men reported having ever been diagnosed with asthma. Generally, self-reported asthma was consistently associated with a poorer testicular function; however, few estimates were statistically significant. Specifically, self-reported asthma was associated with statistically significant lower total sperm count [median: 133 vs. 145 million; adjusted β (95% CI): -0.18 (-0.33 to -0.04) million on cubic-root-transformed scale] and borderline statistically significant lower sperm concentration compared with no self-reported asthma. The association between asthma and total sperm count was of similar magnitude among men with and without allergy. In conclusion, men with self-reported asthma had poorer testicular function than men without asthma. However, the cross-sectional design of the study limits ascertainment of causality.

Rectus diastasis increases risk of burst abdomen in emergency midline laparotomies: a matched case–control study

PURPOSE

Burst abdomen is a serious complication requiring immediate surgical treatment. This study aimed to investigate the association between rectus diastasis and burst abdomen in patients undergoing emergency midline laparotomy.

METHODS

A single-center, retrospective, matched case-control study of patients undergoing emergency midline laparotomy from May 2016 to August 2021 was conducted. Cases (patients who suffered from burst abdomen) were matched 1:4 with controls based on age and sex. Rectus diastasis was evaluated on CT imaging and was defined as a distance of at least three centimeters between the rectus abdominis muscles, three centimeters above the umbilicus. Midline laparotomy aponeurosis closure was standardized during the study period, using a slowly absorbable suture, sutured continuously with small bites of five millimeters and a minimum suture-to-wound ratio of 4:1. The primary outcome was the association between rectus diastasis and burst abdomen, evaluated against other suspected risk factors including obesity, liver cirrhosis, previous laparotomy, midline hernias and active smoking in a multivariate analysis.

RESULTS

A total of 465 patients were included in the study, with 93 cases matched to 372 controls. Eighty-four patients had rectus diastasis (35.5% cases vs. 13.7% controls; p =  < 0.001). Multivariate analysis found rectus diastasis significantly associated with burst abdomen (OR 3.06, 95% CI 1.71-5.47; p =  < 0.001). No other suspected risk factors showed a significant association with burst abdomen.

CONCLUSION

Rectus diastasis was highly associated with an increased risk of burst abdomen after emergency midline laparotomy.

Management and short-term outcomes of patients with small bowel obstruction in Denmark: a multicentre prospective cohort study

AIMS

The optimal management of small bowel obstruction (SBO) remains a matter of debate and treatment varies internationally. In Denmark, a more surgically aggressive strategy has traditionally been used, but to what extent patient outcomes differ from international reports is unknown. This study aimed to describe the current management and outcomes of patients admitted with SBO in Denmark.

METHODS

This was a prospective cohort study conducted at six acute hospitals in Denmark over a 4-month period. Patients aged ≥ 18 years with a clinical or radiological diagnosis of SBO were eligible. Primary outcomes were 30 day morbidity and mortality rates.

RESULTS

316 patients were included during the study period. The median age was 72 years and 56% were female. Diagnosis was made by computed tomography (CT) in 313 patients (99.1%), with the remaining three diagnosed clinically. Non-operative management was the initial strategy in 152 patients (48.1%) and successful in 119 (78.3%). Urgent surgery was performed in the remaining 164 (51.9%), with a laparoscopic approach used in 84 patients (51.2%). The entire cohort had a 30 day mortality rate of 7.3% and a 30 day morbidity rate of 17.1%.

CONCLUSIONS

The management of SBO in Denmark differs markedly to previous international reports, with an almost ubiquitous use of CT for diagnosis and a high proportion of patients undergoing urgent surgery. Despite higher rates of surgery, patient outcomes are broadly similar to reports of more conservative strategies, perhaps due to a reduction in delayed operations.

TRIAL REGISTRATION

Trial registration number: NCT04750811. Trial registration date: 11/02/2021.

Aryl hydrocarbon receptor activity in human breast milk and cryptorchidism: A case-control study within the prospective Norwegian HUMIS cohort

BACKGROUND

The etiology of cryptorchidism remains poorly understood. Endocrine disrupting chemicals can impact estrogen signaling by interacting with aryl hydrocarbon receptor (AhR) activity.

OBJECTIVE

To evaluate whether AhR activity in breast milk samples is associated with cryptorchidism.

METHOD

We conducted a case-control study based on 199 mother-child pairs (n = 91 cases/108 controls) selected from the Norwegian Human Milk Study (2002-2009). We defined cases for cryptorchidism based on maternal reports at 1-, 6-, 12-, and 24- months after birth. Chemically- and biologically stable AhR activity (pg 2,3,7,8-TCDD equivalent (TEQ)/g lipid) was determined by DR- CALUX® assay in the mothers' milk collected at a median of 33 (10th-90th percentile: 18-57) days after delivery. We used multivariate logistic regression to compare AhR activity levels between cases and controls, and linear regression separately, to establish the relationship with the presence of 27 potential EDCs measured in breast milk and AhR activity.

RESULTS

The average estimated daily intake (EDI) of dioxin and (dioxin-like (dl)-compounds via breast milk is 33.7 ± 17.9 pg TEQ/kg bodyweight per day among Norwegian children. There were no significant differences in AhR activation in breast milk samples between cases with cryptorchidism and controls. Among the 27 chemicals measured in breast milk, AhR activity was (borderline) significantly associated with all dl-PCBs, three non-dioxin-like (ndl)-PCBs (PCB-74, PCB-180, PCB-194) and two organochlorine pesticides (OCPs; HCB, β-HCH). No associations between AhR activity and brominated flame retardants (PBDEs) or poly- and perfluoroalkyl substances (PFASs).

CONCLUSION

No association between AhR activity and cryptorchidism was found among Norwegian boys. The average EDI of dioxin and dl-compounds in exclusively breastfed Norwegian infants remains above the safety threshold and, therefore requires further reduction measures. Consistent with a possible role in the observed AhR activity, all dl-PCBs were associated with AhR activity whereas the association was null for either PBDEs or PFASs.

Prenatal and early postnatal exposure to perfluoroalkyl substances and bone mineral content and density in the Odense child cohort

INTRODUCTION

Exposure to perfluoroalkyl substances (PFAS) has been associated with lower bone mineral density (BMD) in animal and human studies, but prospective data from children are limited.

OBJECTIVES

To determine associations between prenatal and early postnatal PFAS exposure and BMD at age 7 years.

METHODS

In the Odense Child Cohort, Denmark, pregnant women were recruited in 2010-2012, and their children were invited for subsequent health examinations. At 12 weeks of gestation the pregnant women delivered a serum sample, and at age 18 months serum was obtained from the child to measure perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) by LC-MS/MS. At age 7 years DXA scans were performed to measure bone mineral content (BMC) and BMD Z-score. PFAS in pregnancy (n = 924) and/or at age 18 months (n = 511) were regressed against DXA measurements, adjusted for maternal education, child height Z-score, sex (for BMC) and for postnatal exposure, additionally duration of total breastfeeding. We additionally performed structural equation models determining combined effects of pre-and postnatal PFAS exposures.

RESULTS

Higher prenatal and early postnatal serum concentrations of all measured PFAS were associated with lower BMC and BMD Z-scores at age 7 years, all estimates were negative although not all significant. For each doubling of prenatal or 18-month exposure to PFDA, BMD Z-scores were lowered by -0.07 (95 % CI -0.10; -0.03) and -0.14 (-0.25; -0.03), respectively after adjustment. Pre- and postnatal PFAS were correlated, but structural equation models suggested that associations with BMD were stronger for 18-month than prenatal PFAS exposure.

DISCUSSION

Bone density is established in childhood, and a reduction in BMD during early childhood may have long-term implication for peak bone mass and lifelong bone health. Future studies of the impact of PFAS exposure on fracture incidence will help elucidate the clinical relevance.

Prenatal and early childhood predictors of intelligence quotient (IQ) in 7-year-old Danish children from the Odense Child Cohort

BACKGROUND

Cognitive development measured as intelligence quotient can predict socioeconomic markers in adulthood. It is therefore of interest to determine predictors of childhood intelligence quotient.

AIM

To assess intelligence quotient scores based on standardised Danish age-appropriate scores and to evaluate potential predictors of intelligence quotient.

MATERIALS

At 7 years of age children in the Odense Child Cohort completed an abbreviated version of the Wechsler intelligence scale for children 5th edition consisting of four subtests (vocabulary, similarities, block design and matrix reasoning) from which the full scale intelligence quotient and verbal comprehension index were estimated. Potential predictors from pregnancy through childhood were collected from questionnaires, birth records and clinical examinations.

METHODS

Intelligence quotient scores were investigated through descriptive statistics and linear regression models.

RESULTS

The mean full scale intelligence quotient among 1375 children was 99.1 (95% confidence interval 98.5; 99.8) points. Higher full scale intelligence quotient scores were observed in girls 100.8 (95% confidence interval 100.0; 101.8) compared to boys 97.6 (96.7; 98.4), and in children of mothers with high and intermediate education 101.7 (100.4; 103.1) and 99.6 (98.7; 100.5), respectively, compared to low education 96.1 (94.9; 97.3). In linear regression analyses, longer maternal education and child sex (girls) remained strong predictors of intelligence quotient at age 7 years. In addition, paternal education, child head circumference and longer duration of breastfeeding were associated with higher intelligence quotient, whereas maternal overweight and obesity before pregnancy was associated with lower intelligence quotient.

CONCLUSIONS

Mean intelligence quotient scores were comparable to the standardised mean intelligence quotient of 100 point of Danish peers. It is important to follow up these children to determine which predictors persist into adulthood.

Anti-androgenic compounds in breast milk and cryptorchidism among Norwegian boys in the HUMIS birth cohort

The prevalence of cryptorchidism has increased over the past decades, yet its origins remain poorly understood. Testis descent is dependent on androgens and likely affected by endocrine disrupting compounds (EDCs), targeting the androgen receptor (AR). We investigated the association between anti-androgenic activity, not derived from natural hormones, in maternal breast milk and impaired testis descent among boys. We performed a case-control study based on 199 breast milk samples from 94 mothers of cryptorchid boys and 105 random non-cryptorchid boys participating in the Norwegian HUMIS (Human Milk Study) cohort. For each participant, apolar, and polar fractions were extracted, and combined to reconstitute a mixture. Anti-androgenic activity was measured in all three fractions using the human cell-based in vitro anti-AR CALUX® assay and expressed in μg of flutamide equivalent, a well-known antiandrogen. Results from fraction analyses were compared among boys with cryptorchidism and controls using multiple logistic regression, controlling for appropriate confounders identified using a directed acyclic graph. Children's daily exposure to anti-androgenic EDCs through breastfeeding was estimated to 78 μg flutamide eq./kg of body weigh/day. The activity was higher in the polar fraction (1.48 ± 1.37 μg flutamide eq./g of milk) mainly representing non-persistent chemicals, in contrast to other fractions. However, the activity in the polar extracts was decreased when in mixtures with the apolar fraction, indicating synergistic interactions. No significant difference in the activity was observed according to cryptorchid status for polar, apolar or mixed breast milk fractions. The study showed anti-androgenic activity in nearly all human milk samples, and at levels higher than the advisory threshold. However, no significant association was observed between cryptorchidism and antiandrogenic activity measured in either polar, apolar, or mixture fractions derived from breast milk.

A case-cohort study of perinatal exposure to potential endocrine disrupters and the risk of cryptorchidism in the Norwegian HUMIS study

BACKGROUND

Exposure to endocrine-disrupting chemicals (EDCs) during the critical period of testicular descent may increase the risk of cryptorchidism and male fertility.

OBJECTIVE

To investigate 27 potential EDCs measured in breast milk as a proxy for perinatal exposure and the risk of cryptorchidism in a prospective cohort.

METHOD

The Norwegian Human Milk Study (2002-2009) enrolled 2606 mother-infant pairs, of which 1326 were mother-son pairs. In a case-cohort design, we studied 641 male infants who had 27 EDCs already quantified in milk samples: 5 organochlorine pesticides, 14 polychlorinated biphenyls (PCBs), 6 brominated flame retardants, and 2 poly- and perfluoroalkyl substances. We defined cases of congenital, recurrent, persistent and ever-reported cryptorchidism based on questionnaires mothers completed when children were 1, 6, 12 and 24 months old. Variable selection via elastic net logistic regression identified the best cryptorchidism predictors while multivariable logistic regression models determined their effect estimates.

RESULTS

The prevalence of reported congenital cryptorchidism was 6.1%, with half spontaneously descending within six months of birth, after which prevalence stabilized between 2.2 and 2.4%. The ever-reported prevalence of cryptorchidism at 1, 6, 12, or 24 months was 12.2%. Elastic net models identified PCB-74 (OR = 1.31, 95% CI: 1.001-1.703), PCB-114 (OR = 1.36, 95% CI: 1.05-1.77), PCB-194 (OR = 1.28, 95% CI: 1.03-1.53) and β-HCH (OR = 1.26, 95% CI: 1.03-1.53 (per interquartile range increase in concentration of EDCs) as best predictors of congenital cryptorchidism. No EDCs were selected for either recurrent or persistent cryptorchidism, and only PCB-194 was selected by elastic net for ever-reported cryptorchidism (OR = 1.23, 95% CI: 1.01-1.51), in contrast to unpenalized multivariable logistic regression, where most of the individual congeners of PCBs showed significant associations.

CONCLUSION

In the largest multi-pollutant analysis to date considering potential confounding from co-exposure to other chemicals, perinatal exposure to PCB-74, PCB-114, PCB-194 and β-HCH were associated with increased odds of congenital cryptorchidism. Many PCBs may falsely be associated with cryptorchidism when assessed individually, due to confounding by highly correlated chemicals. Experimental studies are warranted to confirm our findings.

Association between intake of soft drinks and testicular function in young men

STUDY QUESTION

Is intake of sugar-sweetened beverages (SSB) or artificially sweetened beverages (ASB) associated with testicular function in young men?

SUMMARY ANSWER

Among young men unaware of their semen quality and reproductive hormone levels, intake of SSBs was associated with lower sperm concentration, lower total sperm count, and a lower ratio of serum inhibin-B/FSH.

WHAT IS KNOWN ALREADY

SSBs may adversely impact testicular function, but results are not consistent across studies. Moreover, the associations of ASB, energy-drinks or fruit juices with testicular function are unclear.

STUDY DESIGN, SIZE, DURATION

Young healthy men and unselected for fertility status men enrolled in a cross-sectional study between 2008 and 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 2935 young (median age: 19 years) men enrolled in the study. Intake of SSBs, ASBs, fruit juices, and energy-drinks was assessed with a validated food frequency questionnaire. Testicular function was assessed through conventional semen quality parameters (semen volume, sperm concentration, total count, motility and morphology), testicular volume assessed with ultrasound, and serum reproductive hormone concentrations (total testosterone, free testosterone, E2, inhibin-B, LH, FSH, sex hormone-binding globulin) were measured.

MAIN RESULTS AND THE ROLE OF CHANCE

In multivariable-adjusted analyses, men in the highest category of SSB intake (median: 1.1 servings (∼220 ml)/day) had a 13.2 million/ml lower median sperm concentration (95% CI: -21.0, -5.5) than non-consumers. A similar pattern was observed with total sperm count (-28 million (95% CI: -48, -9)), serum inhibin-B (-12 pg/ml (95% CI: -21, -4)), and inhibin-B/FSH ratio (-9 (95% CI: -18, 0)). The adjusted median difference in sperm concentration and inhibin-B associated with increasing SSB intake by 1 serving (∼200ml)/day at the expense of water was -3.4 million sperm/ml (95% CI: -5.8, -1.0) and -7 pg/ml (95% CI: -11, -3), respectively.

LIMITATIONS, REASONS FOR CAUTION

Inferring causality is limited owing to the cross-sectional design. We adjusted for a number of potential confounders but cannot exclude that unmeasured lifestyle and behavior associated with soft drink intake is associated with testicular function in these young men.

WIDER IMPLICATIONS OF THE FINDINGS

In the largest study to date, intake of SSBs was associated with lower sperm concentration, total sperm count, and serum inhibin-B/FSH ratio, consistent with a direct suppressive effect of SSB intake on testicular function among otherwise healthy men, potentially affecting fertility. However, the observed association between higher SSB intake and lower semen quality does not necessarily imply a decrease in fertility.

STUDY FUNDING/COMPETING INTEREST(S)

Supported by research from the Danish Council for Strategic Research (2101-08-0058), Independent Research Fund Denmark (8020-00218B), European Union (212844), the Kirsten and Freddy Johansen's Foundation (95-103-72087), the Research Fund of the Capital Region of Denmark (A6176), and the NIH (P30DK046200). The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Natural moisturizing factors in children with and without eczema: Associations with lifestyle and genetic factors

BACKGROUND

Filaggrin-derived natural moisturizing factors (NMF) play an important role in skin barrier function and in atopic dermatitis (AD). Its deficiency is associated with dry skin and increased surface pH. Studies on childhood environmental exposures and associations with NMF levels are scarce.

OBJECTIVES

To investigate previous exposures and genetic factors and their associations with NMF levels in young children.

METHODS

In a case-control study nested in a prospective birth cohort (Odense Child Cohort), 169 healthy controls (HC) and 99 children with AD were included consecutively at the age of 7 years based on previous responses from questionnaires administered at 18 months, 3 years and 5 years, pertaining to past medical history, including allergy-specific questions. NMF levels were measured via a stratum corneum tape-stripping technique, genotyping for filaggrin (FLG) gene variants was performed and data on external exposures, including usage of moisturizer and topical steroids, antibiotics and early pet exposures, were obtained from questionnaires.

RESULTS

Natural moisturizing factors levels were significantly lower in AD participants compared to HC (P < 0.001). This significance persisted after stratifying for AD subgroups of present AD, current AD during the last year and previous AD (P < 0.001, P = 0.039, P = 0.009 respectively). There was a significant association between NMF and FLG genotype (P = 0.016, P = 0.002 for HC, AD respectively). NMF levels were negatively correlated with early age moisturizer use (<18 months, P = 0.001) in HC but not significant in AD.

CONCLUSIONS

We found decreased levels of NMF with early moisturizer use and a genetic influence of the FLG variant on these levels. NMF was decreased in the AD subgroup with previous AD compared with HC, which could suggest the persistence of a Th₂ cytokine milieu suppressing these levels.

Maternal polycystic ovary syndrome and attention deficit hyperactivity disorder in offspring at 3 years of age: Odense Child Cohort

INTRODUCTION

Previous data suggested a link between maternal polycystic ovary syndrome (PCOS) and offspring attention deficit hyperactivity disorder (ADHD), which could be mediated by higher prenatal androgen exposure.

MATERIAL AND METHODS

The study was part of the prospective Odense Child Cohort and included 1776 pregnant women, 165 (9%) with PCOS and 1607 (91%) controls. ADHD symptoms at 3 years of age were defined using the parent-reported questionnaire Child Behavior Checklist/1.5-5 (scores >90th centile of Danish national standard). Maternal blood samples were collected in the third trimester measuring total testosterone by mass spectrometry, sex hormone-binding globulin, and calculated free testosterone. Offspring anogenital distance was measured at 3 months of age. Regression models were performed with presence of ADHD symptoms as the dependent variable and adjusted for maternal age, body mass index, parity, smoking status, educational level, and parental psychiatric diagnoses.

RESULTS

ADHD symptoms were present in 105/937 (11%) boys and 72/839 (9%) girls. In boys, maternal PCOS was positively associated with ADHD symptoms (unadjusted odds ratio [OR] 1.91, 95% CI 1.07-3.43, p = 0.03, adjusted OR 2.20, 95% CI 1.20-4.02, p = 0.01), whereas maternal PCOS was not associated with ADHD symptoms in girls. Maternal total testosterone, free testosterone, and offspring anogenital distance were not associated with higher risk of ADHD symptoms in the offspring.

CONCLUSIONS

Higher risk of ADHD in boys born of mothers with PCOS were not associated with maternal third-trimester testosterone levels or offspring anogenital distance.

Reference intervals for trace elements in the general Danish population and their dependence on serum proteins

Reference intervals that indicate the anticipated results of clinical chemistry parameters in a healthy background population are essential for the proper interpretation of laboratory data. In the present study, we analysed major trace elements in blood samples from 400 randomly selected members of the general Danish population. Reference intervals were established for trace elements in both whole blood and serum, and associations with major plasma transport proteins were investigated. In the case of a statistically significant correlation, a corresponding protein-adjusted reference interval was established for comparison with the unadjusted interval. While several trace elements correlated with albumin, ferritin and transferrin, the overall impact of transport proteins was minor and resulted in only marginal changes in the reference intervals. In conclusion, the updated reference intervals for trace elements can be employed without adjusting for plasma protein concentrations.

Impaired fecundity as a marker of health and survival: a Danish twin cohort study

STUDY QUESTION

Is fecundity, measured as self-reported time to first pregnancy (TTP), a marker for subsequent health and survival?

SUMMARY ANSWER

Long TTP was a marker for increased mortality among women and higher hospitalization rates for both women and men.

WHAT IS KNOWN ALREADY

Poor semen quality has been linked to increased mortality and morbidity from a wide range of diseases. Associations among fecundity, health and survival among women are still uncertain and studies on actual measures of fecundity and health outcomes are rare.

STUDY DESIGN, SIZE, DURATION

We performed a prospective cohort study of 7825 women and 6279 men, aged 18 and above with measures on first TTP, who participated in one of the Danish nation-wide twin surveys in 1994 (twins born 1953-1976) and 1998 (twins born 1931-1952). They were followed-up for mortality and hospital admissions from the interview until 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Twins were identified in the Danish Twin Registry and linked to Danish registers. TTP was restricted to the first pregnancy as a categorical outcome with cut-off points at 2, 10 and 18 months. We analysed the association between TTP and survival using a Cox proportional hazards model estimating hazards ratios (HRs) with 95% confidence intervals (CIs). Fine-Gray survival models were used to estimate sub-hazard ratios for specific causes of death allowing for competing risks. Using negative binomial regression, we estimated incidence rate ratios (IRRs) with 95% CIs for all-cause and cause-specific hospitalizations. All analyses were stratified by sex and adjusted for age at interview, birth cohorts, age at first attempt to become pregnant, smoking, years in school and BMI.

MAIN RESULTS AND THE ROLE OF CHANCE

In the total study population, 49.9% of women and 52.7% of men reported a TTP of less than 2 months, 30.8% of women and 29.6% of men reported a TTP of 2-9 months, 6.6% of women and 5.7% of men reported a TTP of 10-17 months, and 13.3% of women and 12.0% of men reported a TTP of 18 months or more. Among 1305 deaths, we found a higher mortality for women (HR = 1.46; 95% CI 1.15, 1.87) with a TTP of ≥18 months relative to those with a TTP of <2 months, while the highest mortality was indicated for men with a TTP of 10-17 months (HR = 1.31; 95% CI 0.98, 1.74). Among 53 799 hospitalizations, we found an increased hospitalization rate among women (HR = 1.21; 95% CI 1.0-1.41) and men (HR = 1.16; 95% CI 1.00-1.35) with a TTP of ≥18 months, and for men with a TTP of 2-9 months (HR = 1.14; 95% CI 1.01-1.30). A dose-response relationship was found for women regarding both mortality (P = 0.022) and hospitalizations (P = 0.018). Impaired fecundity was associated with a wide range of diseases and some causes of death, indicating a multi-factorial causal influence on fecundity, especially among women.

LIMITATIONS, REASONS FOR CAUTION

A major limitation was that fecundity depends on both partners, which was not considered in this study. Moreover, we could not obtain information on a number of potential confounders.

WIDER IMPLICATIONS OF THE FINDINGS

Fecundity seems positively correlated with overall health and may be a universal marker of future health and survival. These results add knowledge to the limited findings showing that reduced fecundity in women and poor semen quality in men may reflect worse health and a shorter life, particularly among women.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by NIH grant HD096468 (M.L.E., T.K.J. and R.L.J.). The authors declare that they have no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Parental comorbidity and medication use in the USA: a panel study of 785 000 live births

STUDY QUESTION

How prevalent is paternal medication use and comorbidity, and are rates of these rising?

SUMMARY ANSWER

Paternal medication use and comorbidity is common and rising, similar to trends previously described in mothers.

WHAT IS KNOWN ALREADY

Maternal medication use and comorbidity has been rising for the past few decades. These trends have been linked to potential teratogenicity, maternal morbidity and mortality and poorer fetal outcomes.

STUDY DESIGN, SIZE, DURATION

This is a Panel (trend) study of 785 809 live births from 2008 to 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We used the IBM© Marketscan®™ database to gather data on demographic information and International Classification of Diseases codes and Charlson comorbidity index (CCI) during the 12 months prior to the estimated date of conception for mothers and fathers. We similarly examined claims of prescriptions in the 3 months prior to conception. We performed companion analyses of medications used for >90 days in the 12 months prior to conception and of any medication use in the 12 months prior to conception.

MAIN RESULTS AND THE ROLE OF CHANCE

We confirmed that both maternal medication use and comorbidity (e.g. hypertension, diabetes, hyperlipidemia) rose over the study period, consistent with prior studies. We found a concurrent rise in both paternal medication use 3 months prior to conception (overall use, 31.5-34.9% during the study period; P < 0.0001) and comorbidity (CCI of ≥1 and 10.6-18.0% over study period; P < 0.0001). The most common conditions seen in the CCI were chronic obstructive pulmonary disease for mothers (6.6-11.6%) and hyperlipidemia for fathers (8.6-13.7%). Similar trends for individual medication classes and specific comorbidities such as hypertension, diabetes and hyperlipidemia were also seen. All primary result trends were statistically significant, making the role of chance minimal.

LIMITATIONS, REASONS FOR CAUTION

As this is a descriptive study, the clinical impact is uncertain and no causal associations may be made. Though the study uses a large and curated database that includes patients from across the USA, our study population is an insured population and our findings may not be generalizable. Mean parental age was seen to slightly increase over the course of the study (<1 year) and may be associated with increased comorbidity and medication use.

WIDER IMPLICATIONS OF THE FINDINGS

As parental comorbidity and certain medication use may impact fecundability, temporal declines in parental health may impact conception, pregnancy and fetal outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

N/A.

Paternal prescription medication before conception: A retrospective cohort study of all births in Denmark 1997-2017

AIM

To study what medication fathers are being prescribed in the months preceding conception.

METHODS

A retrospective cohort study of Danish national registries, comprising all births in Denmark 1997-2017 (1.3 million births). Time trends and absolute levels of paternal prescription medication in the 6 months prior to conception were assessed. While all medications were examined (N = 1335), we focused on the main medication groups, medications that have increased in use over time, and medications for which previous evidence exists of an effect on sperm quality.

RESULTS

The average number of prescriptions increased over the study period (from 0.75 prescriptions to 0.82 per birth). Polypharmacy (three or more prescriptions) increased from less than 8% to 10% of fathers. The use of pain medication, proton-pump inhibitors, selective serotonin reuptake inhibitors and some inhalants have all increased markedly over the last 20 years.

CONCLUSIONS

Potential harm to the offspring done by paternal medication may present an increasing problem. As paternal medication exposure is increasing, examination of generational effects, such as major birth defects, is necessary.

Exposure to perfluoroalkylated substances (PFAS) in relation to fitness, physical activity, and adipokine levels in childhood: The european youth heart study

BACKGROUND

perfluoroalkylated substances (PFAS) are highly persistent chemicals that are able to alter the human metabolism - potentially via disruption of cell signaling pathways mediated by adipokines. Both adiponectin and leptin are influenced by and exert influence on energy storage and energy expenditure, wherefore associations between PFAS and adipokines may be mediated by fitness and fat mass.

OBJECTIVES

the aim of this cross-sectional study was to investigate the association between childhood exposure to PFAS and adipokines (adiponectin and leptin), while considering associations between PFAS and children's level of fitness, physical activity and fat mass to elucidate potential mediation by fitness, physical activity and fat mass.

METHODS

9-year old children from Danish public schools were recruited in the European Youth Heart Study in 1997. For this study only children with valid measures on PFAS (PFOS, PFOA, PFNA, PFDA and PFHxS), adipokines (adiponectin and leptin), fitness, fat mass and co-variates (parity and maternal income) were included (N = 242). Multiple linear regression models with and without conditioning and causal mediation analysis were applied.

RESULTS

this study found inverse associations between PFOA, PFDA and PFHxS and leptin. PFOA was positively associated with adiponectin, whereas PFHxS was inversely associated with adiponectin in boys. Latter association seemed to be mediated by fat mass. Associations with leptin showed indirect effects of fitness and fat mass but were unable to demonstrate significant mediation. Neither PFOS nor PFNA were associated with the outcome.

DISCUSSION

these results may indicate a favorable leptin profile with increasing PFAS, although the results could be driven by residual negative confounding from socio-economic factors and mediation by fitness and fat mass.

Psychological stress, stressful life events, male factor infertility, and testicular function: a cross-sectional study

OBJECTIVE

To assess the association between psychological stress and male factor infertility as well as testicular function (semen quality, serum reproductive hormones) and erectile dysfunction.

DESIGN

Cross-sectional study.

SETTING

University Hospital-based research center.

PATIENTS

Men with impaired semen quality were included from infertile couples, and men with naturally conceived pregnant partners were used as a reference population.

INTERVENTIONS

Participants completed a questionnaire on health and lifestyle, including a 14-item questionnaire about self-rated psychological stress symptoms and stressful life event (SLEs), had a physical examination performed, delivered a semen sample and had a blood sample drawn.

MAIN OUTCOMES

Differences in stress scores (calculated from self-reported stress symptoms) and SLEs between infertile and fertile men were assessed in crude and fully adjusted linear regression models. Secondary outcomes were semen quality, serum reproductive hormones, and erectile dysfunction.

RESULTS

Of 423 men, 176 (41.6%) experienced at least one SLE in the 3 months prior to inclusion (50.4%/36.9%: infertile/fertile men, P = .03); β-coefficient and 95% confidence interval for the difference between the groups on the transformed scale in fully adjusted linear regression models was 0.18 (0.06, 0.30). However, there were no differences in psychological stress symptoms between the two groups (β-coefficient and 95% confidence interval) on the transformed scale (0.14; -0.02, 0.30). No association between stress (self-reported stress symptoms and SLEs) and testicular function or with erectile dysfunction was found in any of the men.

CONCLUSION

Infertile men reported a higher number of SLEs than fertile men but did not report more psychological stress symptoms. Distress and SLEs were not associated with reduced male reproductive function.

Higher circulating plasma polychlorinated biphenyls (PCBs) in fit and lean children: The European youth heart study

BACKGROUND

Lipophilic compounds such as polychlorinated biphenyls (PCBs) are primarily stored in adipose tissue, but exercise-induced lipolysis is able to release PCBs from the adipose tissue into the circulation. The plasma concentration, distribution and metabolism of PCBs can thus vary much among individuals due to inter-human variations in lifestyle behavior and pharmacokinetics.

OBJECTIVES

We examined the observational relationship of circulating plasma PCB concentrations with cardiorespiratory fitness, engagement in vigorous physical activity and fat mass in a healthy Danish child population.

METHODS

Data on ∑PCB (PCB138, PCB153 and PCB180), cardiorespiratory fitness, skinfold thickness and objectively measured physical activity of 509 children derived from the Danish sub-study of The European Youth Heart Study.

RESULTS

Higher fitness and greater leanness were associated with elevated plasma ∑PCB in both boys and girls. The associations were independent of each other and persisted after controlling for socio-economic status and duration of breastfeeding. We observed an almost three-fold increase in plasma ∑PCB level in the most fit/least fat children relative to the least fit/most fat children. The association between fatness and ∑PCB was strongest for boys as girls, and especially pubertal girls, displayed lower decrease in plasma ∑PCB with higher fat mass.

DISCUSSION

Our findings suggest that increased lipolysis stimulates the release of PCBs into the vasculature. The consequence is higher plasma levels of PCB in very fit and lean subjects. This scenario is likely to cause negative confounding in epidemiological observations of PCB and cardio-metabolic health. At the same time adipose tissue may play a dual role in promoting adverse health and providing a relatively safe place to store PCB.

Association of Dietary Patterns With Testicular Function in Young Danish Men

IMPORTANCE

Diet may play a role in testicular function, but data on how adherence to different diet patterns influences human testicular function are scarce.

OBJECTIVE

To determine whether adherence to specific dietary patterns is associated with testicular function in young men.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study included 2935 young Danish men unselected regarding fertility status who were enrolled from April 1, 2008, through May 31, 2017. Data were analyzed from July 1, 2017, to January 30, 2019.

EXPOSURES

Dietary patterns identified with principal component analysis based on responses to a validated food frequency questionnaire.

MAIN OUTCOMES AND MEASURES

Standard semen quality assessment; serum concentrations of testosterone, free testosterone, estradiol, inhibin B, follicle-stimulating hormone, luteinizing hormone, and sex hormone-binding globulin; and testicular volume measured with ultrasonography.

RESULTS

Among the 2935 participants included in the analysis, median age was 19 (interquartile range, 19-20) years and 2290 (78.0%) had normal body mass index. The 4 dietary patterns identified included Western, prudent, open-sandwich (a traditional Danish eating pattern), and vegetarianlike. The greatest adherence to the prudent pattern was associated with the highest total sperm count (median, 167 [95% CI, 146-183] million), followed by adherence to vegetarianlike (median, 151 [95% CI, 134-168] million) and open-sandwich (median, 146 [95% CI, 131-163] million) patterns. Adherence to the Western pattern was associated with the lowest total sperm count (median, 122 [95% CI, 109-138] million), which was significantly lower than sperm count in the other 3 diet patterns. After adjusting for confounders, the median total sperm count for men in the highest quintile of adherence to the Western pattern was 26 million lower (95% CI, -42 to -9 million) than for men in the lowest quintile of adherence to this pattern. Conversely, the median total sperm count of men in the highest quintile of adherence to the prudent pattern was 43 million (95% CI, 23-63 million) higher than that of men in the lowest quintile. Men with the highest adherence to the Western pattern had a lower median ratio of inhibin B to follicle-stimulating hormone (-12 [95% CI, -20 to -3]) and higher median ratio of free testosterone to luteinizing hormone (10 [95% CI, 2-19]) compared with men with lowest adherence to this pattern.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, adherence to generally healthy diet patterns was associated with better semen quality, with potentially more favorable fertility potential among adult men.

Average sperm count remains unchanged despite reduction in maternal smoking: results from a large cross-sectional study with annual investigations over 21 years

STUDY QUESTION

How are temporal trends in lifestyle factors, including exposure to maternal smoking in utero, associated to semen quality in young men from the general population?

SUMMARY ANSWER

Exposure to maternal smoking was associated with lower sperm counts but no overall increase in sperm counts was observed during the study period despite a decrease in this exposure.

WHAT IS KNOWN ALREADY

Meta-analyses suggest a continuous decline in semen quality but few studies have investigated temporal trends in unselected populations recruited and analysed with the same protocol over a long period and none have studied simultaneous trends in lifestyle factors.

STUDY DESIGN, SIZE, DURATION

Cross-sectional population-based study including ~300 participants per year (total number = 6386) between 1996 and 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study is based on men from the Greater Copenhagen area, Denmark, with a median age of 19 years, and unselected with regard to fertility status and semen quality. The men delivered a semen sample, had a blood sample drawn and a physical examination performed and answered a comprehensive questionnaire, including information on lifestyle and the mother's pregnancy. Temporal trends in semen quality and lifestyle were illustrated graphically, and trends in semen parameters and the impact of prenatal and current lifestyle factors were explored in multiple regression analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

Throughout the study period, 35% of the men had low semen quality. Overall, there were no persistent temporal trends in semen quality, testicular volume or levels of follicle-stimulating hormone over the 21 years studied. The men's alcohol intake was lowest between 2011 and 2016, whereas BMI, use of medication and smoking showed no clear temporal trends. Parental age increased, and exposure in utero to maternal smoking declined from 40% among men investigated in 1996-2000 to 18% among men investigated in 2011-2016. Exposure to maternal smoking was associated with lower sperm counts but no overall increase in sperm counts was observed despite the decrease in this exposure.

LIMITATIONS, REASONS FOR CAUTION

Information of current and prenatal lifestyle was obtained by self-report, and the men delivered only one semen sample each.

WIDER IMPLICATIONS OF THE FINDINGS

The significant decline in in utero exposure to maternal smoking, which was not reflected in an overall improvement of semen quality at the population level, suggest that other unknown adverse factors may maintain the low semen quality among Danish men.

STUDY FUNDING/COMPETING INTEREST(S)

The study has received financial support from the ReproUnion; the Research fund of Rigshospitalet, Copenhagen University Hospital; the European Union (Contract numbers BMH4-CT96-0314,QLK4-CT-1999-01422, QLK4-CT-2002-00603, FP7/2007-2013, DEER Grant agreement no. 212844); the Danish Ministry of Health; the Danish Environmental Protection Agency; A.P. Møller and wife Chastine McKinney Møllers foundation; and Svend Andersens Foundation. None of the funders had any role in the study design, collection, analysis or interpretation of data, writing of the paper or publication decisions.

TRIAL REGISTRATION NUMBER

N/A.

Anogenital distance is associated with semen quality but not reproductive hormones in 1106 young men from the general population

STUDY QUESTION

Is anogenital distance (AGD) associated with semen quality and reproductive hormones in men from the general population?

SUMMARY ANSWER

Short AGD measured from the anus to the base of scrotum (AGDAS) was associated with reduced sperm counts and morphology but not with sperm motility or reproductive hormones.

WHAT IS KNOWN ALREADY

AGD is longer in males than in females. In rodents, AGD is a well-established and sensitive marker of disruption during the masculinization programming window in utero and it has been suggested to be so in humans as well. Therefore, the average AGD would be expected to be shorter in men with poor semen quality, which some studies have confirmed while others have not.

STUDY DESIGN, SIZE, DURATION

This cross-sectional population-based study was of 1106 men included between 2012 and 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Men from the general Danish population (median age 19 years), unselected with regard to fertility status and semen quality, delivered a semen sample, had a blood sample drawn, which was analyzed for concentrations of reproductive hormones, and answered a comprehensive questionnaire. They also had a physical examination performed including determination of AGD measured as the distance between anus and scrotum (AGDAS) and penis (AGDAP). Odds ratios (OR) and 95% CI were estimated for a man having abnormal semen parameters according to the World Health Organization's reference values or a low/high concentration of reproductive hormones (defined as the lowest or highest 10%) depending on AGD. AGD was categorized in four strata: ≤10th percentile, 10th-30th percentile, 30th-50th percentile and >50th percentile.

MAIN RESULTS AND THE ROLE OF CHANCE

Men with the 10% shortest AGDAS had a more than doubled risk (OR: 2.19, 95% CI: 1.40-3.42) of being in the subfertile range for either sperm concentration (<15 million/mL) or sperm morphology (<4%) compared to men with AGDAS above the median (reference). Men in the 10th-30th percentile also had an increased OR of 1.48 (95% CI: 1.06-2.08) but not men in the 30th-50th percentile (OR: 1.14, 95% CI: 0.81-1.62). AGDAP was only weakly related to semen quality. AGD was not associated with testicular volume or any of the reproductive hormones.

LIMITATIONS, REASONS FOR CAUTION

Limitations include the potential non-differential misclassification of reproductive outcomes based on a single semen and blood sample and some between-examiner differences in AGD measurements which introduces noise and may result in an underestimation of observed associations.

WIDER IMPLICATIONS OF THE FINDINGS

Our study of men from the general population confirmed associations between AGD and semen quality, supporting the hypothesis that AGD in humans could be a marker of fetal testicular development. This suggests that the low semen quality in Danish men may partly be explained by prenatal factors.

STUDY FUNDING/COMPETING INTEREST(S)

The study has received financial support from the ReproUnion (L.P.); the Research fund of Rigshospitalet, Copenhagen University Hospital (N.J.); Grants R01ES016863-04 and R01ES016863-02S4; National Institute of Environmental Health Sciences (NIEHS) and National Institute of Environmental Health Sciences grant (P30ES023515) (S.S.); the European Union (Contract numbers BMH4-CT96-0314, QLK4-CT-1999-01422, QLK4-CT-2002-00603, FP7/2007-2013, DEER Grant agreement no. 212844); the Danish Ministry of Health; the Danish Environmental Protection Agency; A.P. Møller and wife Chastine McKinney Møllers foundation; and Svend Andersens Foundation. None of the funders had any role in the study design, collection, analysis or interpretation of data, writing of the paper or publication decisions. The authors have nothing to declare.

TRIAL REGISTRATION NUMBER

N/A.

Prenatal pesticide exposure associated with glycated haemoglobin and markers of metabolic dysfunction in adolescents

BACKGROUND

Pesticide exposure has been associated with increased risk of diabetes mellitus in adults, but potential effects of prenatal exposure on glucose regulation have not been investigated. The aim of this study was to investigate if maternal occupational pesticide exposure in pregnancy was associated with glycated haemoglobin A1c (HbA1c) in adolescents and whether an association was modified by sex and paraoxonase-1 (PON1) Q192R polymorphism.

METHODS

A prospective cohort study of children whose mothers were either occupationally exposed or unexposed to pesticides in early pregnancy. At age 10-to-16 years, the children (n = 168) underwent clinical examinations including pubertal stage assessment (accepted by 141 children) and blood sampling. PON1 Q192R genotype was available for 139 children and 103 mothers. The main outcome measure was HbA1c but other relevant biomarkers were also included.

RESULTS

Prenatal pesticide exposure was associated with a 5.0% (95% confidence interval: 1.8; 8.2) higher HbA1c compared to unexposed children after adjustment for confounders. After stratification, the association remained significant for girls (6.2% (1.6; 11.1)) and if the child or the mother had the PON1 192R-allele (6.1% (1.6; 10.8) and 7.1% (2.0; 12.6), respectively). Besides, an exposure-related increase was seen for the leptin-to-adiponectin ratio, for plasminogen activator inhibitor type-1 in girls, and for interleukin-6 in children whose mothers had the R-allele.

CONCLUSION

Prenatal pesticide exposure was associated with higher HbA1c and changes in related biomarkers in adolescents. Our results suggest an adverse effect on glucose homeostasis and support previous findings from this cohort of an exposure-associated metabolic risk profile with higher susceptibility related to female sex and the PON1 192R-allele.

Gestational Diabetes Mellitus: Does One Size Fit All? A Challenge to Uniform Worldwide Diagnostic Thresholds

OBJECTIVE

To define the prevalence and pregnancy outcomes related to elevated fasting venous plasma glucose (FVPG) in a Danish pregnancy cohort.

RESEARCH DESIGN AND METHODS

This was an observational cohort study including 1,516 women without gestational diabetes mellitus (GDM) by Danish criteria. FVPG measured at 28 weeks' gestation was related to pregnancy outcomes.

RESULTS

With use of the World Health Organization (WHO) 2013 threshold of FVPG ≥5.1 mmol/L, 40.1% of the cohort qualified as having GDM. There was no evidence of excess fetal growth, hypertension in pregnancy, or cesarean delivery in women with FVPG <5.6 mmol/L.

CONCLUSIONS

The WHO 2013 FVPG threshold for GDM is unsuitable for Denmark. It inappropriately labels as having GDM an unmanageably large number of women who are at low absolute risk of pregnancy complications.

Anogenital distance as a phenotypic signature through infancy

BackgroundAnogenital distance (AGD) has been suggested to represent a phenotypic signature reflecting in utero androgen action. However, it is not known whether an individual's AGD at birth correlates to the AGD later in life. We investigate correlations of AGD between 3 and 18 months of age and assess reproducibility of measurements.MethodsWe measured AGD from anus to scrotum (AGDas) and to penis (AGDap) in 407 boys, and to posterior fourchette (AGDaf) and clitoris (AGDac) in 282 girls. Each measure was repeated three times at 3 and 18 months of age, and some children were, furthermore, examined by two different examiners. We assessed age-related changes and reproducibility of measurements.ResultsAGD increased between the two examinations and correlated within the child. A large proportion of the observed variation in AGD was due to true differences between the children (AGDas: 62%, AGDap: 40%, AGDaf: 30%, AGDac: 21%), and measurement error due to between- and within-examiner variation was low.ConclusionsOur study showed that measures of AGD within a child correlated during infancy, especially in boys and particularly for AGD measured as the distance between anus and scrotum. A planned cohort follow-up through childhood and puberty will reveal whether AGD represents a phenotypic signature throughout life.

Individual testosterone decline and future mortality risk in men

OBJECTIVE

Male aging is characterized by a decline in testosterone (TS) levels with a substantial variability between subjects. However, it is unclear whether differences in age-related changes in TS are associated with general health. We investigated associations between mortality and intra-individual changes in serum levels of total TS, SHBG, free TS and LH during a ten-year period with up to 18 years of registry follow-up.

DESIGN

1167 men aged 30-60 years participating in the Danish Monitoring Trends and Determinants of Cardiovascular Disease (MONICA1) study and who had a follow-up examination ten years later (MONICA10) were included. From MONICA10, the men were followed up to 18 years (mean: 15.2 years) based on the information from national mortality registries via their unique personal ID numbers.

METHODS

Cox proportional hazard models were used to investigate the association between intra-individual hormone changes and all-cause, CVD and cancer mortalities.

RESULTS

A total of 421 men (36.1%) died during the follow-up period. Men with most pronounced decline in total TS (<10th percentile) had a higher all-cause mortality risk compared to men within the 10th to 90th percentile (hazard ratio (HR): 1.60; 95% confidence interval (CI): 1.08-2.36). No consistent associations were seen in cause-specific mortality analyses.

CONCLUSION

Our study showed that higher mortality rates were seen among the men who had the most pronounced age-related decline in TS, independent of their baseline TS levels.

Presence and localization of bacteria in the bovine endometrium postpartum using fluorescence in situ hybridization

The aim of this study was to investigate bacterial invasiveness of the bovine endometrium during the postpartum period. Fluorescence in situ hybridization was applied to endometrial biopsies using probes for Fusobacterium necrophorum, Porphyromonas levii, Trueperella pyogenes, Escherichia coli and a probe for bacteria in general (the overall domain Bacteria) to determine their tissue localization. Holstein cows were sampled at three time points postpartum (T1: 4-12 days postpartum, T2: 24-32 days postpartum and T3: 46-54 days postpartum). At T1, cows were clinically scored as having a uterine infection based on presence of a brownish, fetid vaginal discharge or as normal if having normal lochia. An endometrial biopsy was taken from all cows at T1 (n = 57). Endometrial biopsies were taken from the same cows at T2 and T3 if allowed by the size of the cervical canal and if the cow had not been inseminated. Fifty and 39 biopsies were obtained at T2 and T3, respectively. The biopsies were evaluated for inflammation and for presence and localization of bacteria. When analyzed by the probe for the entire domain Bacteria, bacteria were found in most biopsies irrespectively of time (T1: 79.0%, T2: 82.0%, T3: 89.7%). Fusobacterium necrophorum and Porphyromonas levii were often present in the endometrium at T1 (61.1% and 47.8%, respectively), but the prevalence decreased significantly over time. Trueperella pyogenes and Escherichia coli were less prevalent at T1 (8.8% and 10.5%, respectively) and their prevalence also decreased significantly over time. Fusobacterium necrophorum and Porphyromonas levii were often co-localized intraepithelially or in the lamina propria. Trueperella pyogenes and Escherichia coli were located only on the endometrial surface. Due to the high prevalence of tissue invasiveness, these findings emphasize the importance of Fusobacterium necrophorum and Porphyromonas levii in postpartum uterine disease of cattle and indicate that tissue invasiveness is an important aspect of the pathogenesis.

Bacterial invasion of the uterus and oviducts in bovine pyometra

Pyometra is a common disease of cattle that causes infertility and thereby financial losses to the cattle industry. Bacteria involved in the development and progression of pyometra have been investigated by microbial culture but their tissue invading abilities, which is an important aspect of bacterial pathogenicity and development of lesions, have not been investigated. Bacterial invasion of the uterus and oviducts was studied in 21 cows diagnosed with pyometra at the time of slaughter by applying fluorescence in situ hybridization using probes targeting 16S ribosomal RNA of Fusobacterium necrophorum, Porphyromonas levii, Trueperella pyogenes and the overall bacterial domain Bacteria. Fusobacterium necrophorum and P. levii were found to invade the endometrium, especially if the endometrium was ulcerated, and penetrated deep into the lamina propria. These species co-localized within the tissue thus indicating a synergism. Trueperella pyogenes did not invade the uterine tissue. In addition to endometrial lesions, most cows with pyometra also had salpingitis but without significant bacterial invasion of the oviductal wall.

Complications after emergency laparotomy beyond the immediate postoperative period - a retrospective, observational cohort study of 1139 patients

Mortality and morbidity occur commonly following emergency laparotomy, and incur a considerable clinical and financial healthcare burden. Limited data have been published describing the postoperative course and temporal pattern of complications after emergency laparotomy. We undertook a retrospective, observational, multicentre study of complications in 1139 patients after emergency laparotomy. A major complication occurred in 537/1139 (47%) of all patients within 30 days of surgery. Unadjusted 30-day mortality was 20.2% and 1-year mortality was 34%. One hundred and thirty-seven of 230 (60%) deaths occurred between 72 h and 30 days after surgery; all of these patients had complications, indicating that there is a prolonged period with a high frequency of complications and mortality after emergency laparotomy. We conclude that peri-operative, enhanced recovery care bundles for preventing complications should extend their focus on continuous complication detection and rescue beyond the first few postoperative days.

Early pregnancy angiogenic markers and spontaneous abortion: an Odense Child Cohort study

BACKGROUND

Spontaneous abortion is the most commonly observed adverse pregnancy outcome. The angiogenic factors soluble Fms-like kinase 1 and placental growth factor are critical for normal pregnancy and may be associated to spontaneous abortion.

OBJECTIVE

We investigated the association between maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor, and subsequent spontaneous abortion.

STUDY DESIGN

In the prospective observational Odense Child Cohort, 1676 pregnant women donated serum in early pregnancy, gestational week <22 (median 83 days of gestation, interquartile range 71-103). Concentrations of soluble Fms-like kinase 1 and placental growth factor were determined with novel automated assays. Spontaneous abortion was defined as complete or incomplete spontaneous abortion, missed abortion, or blighted ovum <22+0 gestational weeks, and the prevalence was 3.52% (59 cases). The time-dependent effect of maternal serum concentrations of soluble Fms-like kinase 1 and placental growth factor on subsequent late first-trimester or second-trimester spontaneous abortion (n = 59) was evaluated using a Cox proportional hazards regression model, adjusting for body mass index, parity, season of blood sampling, and age. Furthermore, receiver operating characteristics were employed to identify predictive values and optimal cut-off values.

RESULTS

In the adjusted Cox regression analysis, increasing continuous concentrations of both soluble Fms-like kinase 1 and placental growth factor were significantly associated with a decreased hazard ratio for spontaneous abortion: soluble Fms-like kinase 1, 0.996 (95% confidence interval, 0.995-0.997), and placental growth factor, 0.89 (95% confidence interval, 0.86-0.93). When analyzed by receiver operating characteristic cut-offs, women with soluble Fms-like kinase 1 <742 pg/mL had an odds ratio for spontaneous abortion of 12.1 (95% confidence interval, 6.64-22.2), positive predictive value of 11.70%, negative predictive value of 98.90%, positive likelihood ratio of 3.64 (3.07-4.32), and negative likelihood ratio of 0.30 (0.19-0.48). For placental growth factor <19.7 pg/mL, odds ratio was 13.2 (7.09-24.4), positive predictive value was 11.80%, negative predictive value was 99.0%, positive likelihood ratio was 3.68 (3.12-4.34), and negative likelihood ratio was 0.28 (0.17-0.45). In the sensitivity analysis of 54 spontaneous abortions matched 1:4 to controls on gestational age at blood sampling, the highest area under the curve was seen for soluble Fms-like kinase 1 in prediction of first-trimester spontaneous abortion, 0.898 (0.834-0.962), and at the optimum cut-off of 725 pg/mL, negative predictive value was 51.4%, positive predictive value was 94.6%, positive likelihood ratio was 4.04 (2.57-6.35), and negative likelihood ratio was 0.22 (0.09-0.54).

CONCLUSION

A strong, novel prospective association was identified between lower concentrations of soluble Fms-like kinase 1 and placental growth factor measured in early pregnancy and spontaneous abortion. A soluble Fms-like kinase 1 cut-off <742 pg/mL in maternal serum was optimal to stratify women at high vs low risk of spontaneous abortion. The cause and effect of angiogenic factor alterations in spontaneous abortions remain to be elucidated.

Longitudinal Associations of Exposure to Perfluoroalkylated Substances in Childhood and Adolescence and Indicators of Adiposity and Glucose Metabolism 6 and 12 Years Later: The European Youth Heart Study

OBJECTIVE

To investigate the long-term association of exposure to perfluoroalkylated substances, including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), during childhood (9 years) and adolescence (15 years) on indicators of adiposity and glucose metabolism in adolescence (15 years) and young adulthood (21 years). Secondarily, we aim to clarify the degree of tracking of exposure from childhood into young adulthood.

RESEARCH DESIGN AND METHODS

Data derived from a large multicenter prospective cohort study, in which the same participants have been observed from childhood (N = 590), during adolescence (N = 444), and into young adulthood (N = 369). Stored plasma samples were analyzed for PFOS and PFOA. Indicators of adiposity comprising body height, body weight, sum of four skinfolds, and waist circumference, as well as indicators of glucose metabolism, comprising fasting blood glucose, triglyceride, and insulin levels, β-cell function, and insulin resistance, have been collected at all study waves. Multiple linear regression was applied in order to model earlier exposure on later outcome while controlling for baseline outcome levels, sex, age, and socioeconomic factors.

RESULTS

Childhood exposure to PFOS was associated with indicators of adiposity at 15 years of age that are displayed in elevated BMI, skinfold thickness, and waist circumference, as well as increased skinfold thickness and waist circumference at 21 years of age. PFOA exposure in childhood was associated with decreased β-cell function at 15 years of age. We did not observe associations between exposure during adolescence and indicators of adiposity and glucose metabolism in young adulthood.

CONCLUSIONS

This study found evidence for childhood exposure to PFOS and PFOA predicting adiposity at 15 and 21 years of age and impaired β-cell function at 15 years of age, respectively.

Low Testosterone: A Risk Marker Rather Than a Risk Factor for Type 2 Diabetes

CONTEXT

Low serum T levels have been associated with type 2 diabetes (T2D) and cardiovascular disease. However, it is unresolved whether low T is a risk factor or rather a risk marker for these conditions.

OBJECTIVE

The objective of the study was to investigate serum levels of total T, SHBG, free T, estradiol, LH, and FSH and the subsequent risk of T2D and/or cardiovascular disease.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study consisting of 5350 men from the general population aged 30-70 years at baseline, examined between 1982 and 2001 and followed with complete registry follow-up until December 2011, ie, up to 29 years of follow-up.

MAIN OUTCOME MEASURES

T2D outcomes defined as the first diagnosis of T2D and cardiovascular outcomes defined as first diagnosis of either ischemic heart disease or stroke (ischemic and hemorrhagic stroke).

RESULTS

In Cox proportional hazards models, a significantly negative association between T quartile and the risk of T2D was seen. Similarly, men with SHBG in the highest quartile had a decreased risk of developing T2D (nonsmokers: hazard ratio 0.30, 95% confidence interval 0.14-0.63; smokers: hazard ratio 0.40, 95% confidence interval 0.20-0.78). Similar trends were seen for free T, however, insignificant in the fully adjusted analysis. No associations were seen for estradiol, LH, and FSH. A less consistent pattern was seen for the hormones in relation to CVD outcomes; nonsmoking men showed a pattern of higher levels of total T, SHBG, and LH being negatively associated with ischemic heart disease and less pronounced for stroke, whereas in smokers higher levels of total T, free T, and LH were positively associated with the two CVD outcomes.

CONCLUSIONS

The observed negative associations of T and SHBG with T2D, but no association to LH and free T, indicates that low T in men who develop T2D is a marker of the disease rather than primary hypogonadism being a causal risk factor.

Application of Fluorescent In Situ Hybridization for Specific Diagnosis of Pneumocystis carinii Pneumonia in Foals and Pigs

Fluorescent in situ hybridization, immunohistochemistry, and Grocott's methenamine-silver nitrate staining were compared as diagnostic methods for Pneumocystis carinii pneumonia in formalin-fixed lung tissue from foals and pigs. An oligonucleotide probe targeting 18S ribosomal RNA of P. carinii was designed for in situ hybridization, and a commercially available monoclonal antibody was used for immunohistochemistry. Samples from six foals and 10 pigs with P. carinii pneumonia, as verified by Grocott's methenaminesilver nitrate staining, were examined concurrently with samples from seven animals with pneumonia caused by other pathogens. Fluorescent in situ hybridization showed distinctive positive reactions for P. carinii in all test samples. The immunohistochemical procedure, however, only revealed P. carinii in the foals. The number of P. carinii organisms observed by fluorescent in situ hybridization and immunohistochemistry far exceeded the number of organisms stained by Grocott's methenamine-silver nitrate staining. The results show that fluorescent in situ hybridization targeting ribosomal RNA can provide a specific diagnosis of P. carinii pneumonia in foals and pigs.

Prenatal pesticide exposure and PON1 genotype associated with adolescent body fat distribution evaluated by dual X-ray absorptiometry (DXA)

Many modern pesticides have endocrine disrupting abilities and early-life exposure may affect growth and disease risk later in life. Previously, we reported associations between prenatal pesticide exposure and higher childhood body fat content measured by anthropometry. The associations were affected by child PON1 Q192R genotype. We aimed to study whether prenatal pesticide exposure was still associated with body fat content and distribution in the children at puberty and the potential impact of both maternal and child PON1 Q192R genotype. In this prospective cohort study of 247 children born by occupationally exposed or unexposed women (greenhouse workers and controls) two follow-up examinations (age 10-15 and 11-16 years) including simple anthropometry, skinfold measurements, pubertal staging and blood sampling were performed. Total and regional fat% was determined by dual X-ray absorptiometry (DXA) at age 10-15. Prenatal pesticide exposure was associated with increased total, android, and gynoid fat percentage (DXA) at age 10-15 years after adjustment for sex, socioeconomic status, and puberty (all β = 0.5 standard deviation score (SDS) p < 0.05). Stratified by sex, the associations were significant in girls (total fat: β = 0.7 SDS, android-gynoid ratio: β = 0.1, both p < 0.05), but not in boys. Carrying the R-allele (child or mother, separately, or both) augmented the differences between exposed and unexposed children (total fat: β = 1.0 SDS, β = 0.8 SDS, p < 0.05, respectively, and β = 1.2 SDS, p < 0.01). No exposure-related differences were found if either the child or mother had the QQ wild-type. At age 11-16, exposed children tended to have a higher total fat% estimated by skinfolds than unexposed children (p = 0.06). No significant associations between prenatal exposure and body mass index or waist circumference were found. Prenatal pesticide exposure was associated with higher adolescent body fat content, including android fat deposition, independent of puberty. Girls appeared more susceptible than boys. Furthermore, the association depended on maternal and child PON1 Q192R genotype.

Prenatal exposure to persistent organochlorine pollutants is associated with high insulin levels in 5-year-old girls

BACKGROUND

Several persistent organochlorine pollutants (POPs) possess endocrine disrupting abilities, thereby potentially leading to an increased risk of obesity and metabolic diseases, especially if the exposure occurs during prenatal life. We have previously found associations between prenatal POP exposures and increased BMI, waist circumference and change in BMI from 5 to 7 years of age, though only among girls with overweight mothers.

OBJECTIVES

In the same birth cohort, we investigated whether prenatal POP exposure was associated with serum concentrations of insulin and leptin among 5-year-old children, thus possibly mediating the association with overweight and obesity at 7 years of age.

METHODS

The analyses were based on a prospective Faroese Birth Cohort (n=656), recruited between 1997 and 2000. Major POPs, polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyldichloroethylene (DDE) and hexachlorobenzene (HCB), were measured in maternal pregnancy serum and breast milk. Children were followed-up at the age of 5 years where a non-fasting blood sample was drawn; 520 children (273 boys and 247 girls) had adequate serum amounts available for biomarker analyses by Luminex® technology. Insulin and leptin concentrations were transformed from continuous to binary variables, using the 75th percentile as a cut-off point. Multiple logistic regression was used to investigate associations between prenatal POP exposures and non-fasting serum concentrations of insulin and leptin at age 5 while taking into account confounders.

RESULTS

Girls with highest prenatal POP exposure were more likely to have high non-fasting insulin levels (PCBs 4th quartile: OR=3.71; 95% CI: 1.36, 10.01. DDE 4th quartile: OR=2.75; 95% CI: 1.09, 6.90. HCB 4th quartile: OR=1.98; 95% CI: 1.06, 3.69) compared to girls in the lowest quartile. No significant associations were observed with leptin, or among boys. A mediating effect of insulin or leptin on later obesity was not observed.

CONCLUSION

These findings suggest, that for girls, prenatal exposure to POPs may play a role for later development of metabolic diseases by affecting the level of insulin.

Vitamin D insufficiency is associated with increased risk of first-trimester miscarriage in the Odense Child Cohort

BACKGROUND

Miscarriage is the most common negative outcome of pregnancy, and identification of modifiable risk factors is potentially of great importance for public health. Low vitamin D concentrations in pregnancy are widespread worldwide, and vitamin D deficiency is implicated in immune cell regulation at the feto-maternal interface and several diseases of pregnancy.

OBJECTIVE

We investigated whether 25-hydroxyvitamin D serum concentration was a modifiable risk factor for early miscarriage.

DESIGN

In a prospective cohort study of 1683 pregnant women donating serum before gestational week 22, we investigated the association between maternal serum concentrations of serum 25-hydroxyvitamin D [25(OH)D] and the risk of subsequent miscarriage (n = 58).

RESULTS

The adjusted hazard of first-trimester miscarriage was lower with higher 25(OH)D concentrations (HR: 0.98; 95% CI: 0.96, 0.99). Concentrations of 25(OH)D <50 nmol/L were associated with a >2-fold increased adjusted HR for miscarriage (HR: 2.50; 95% CI: 1.10, 5.69). Concentrations of 25(OH)D were not associated with an increased risk of second-trimester miscarriage.

CONCLUSIONS

We found an association between 25(OH)D and first-trimester miscarriages, suggesting vitamin D as a modifiable risk factor for miscarriage. To test this hypothesis, randomized controlled trials should investigate the possible effect of vitamin D supplementation to increase 25(OH)D concentrations in early pregnancy, or before conception, to decrease risk of miscarriage. This trial was registered at clinicaltrials.gov as NCT02434900.

Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls

BACKGROUND

Endocrine disrupting industrial chemicals, such as polychlorinated biphenyls (PCBs), are suspected to adversely affect male reproductive functions.

OBJECTIVES

The Faroe Islands community exhibits an unusually wide range of exposures to dietary contaminants, and in this setting we examined the possible association between PCB exposure and semen quality and reproductive hormones in fertile Faroese men.

METHODS

Participants in this cross-sectional study include 266 proven fertile men residing in the Faroe Islands. PCB levels and hormone profiles were measured in serum samples taken at the clinical examination that included semen quality parameters.

RESULTS

A significant positive association was seen between serum-PCB and the testosterone/estradiol ratio (p=0.04). In the unadjusted analyses, elevated PCB exposure was associated with increased serum concentrations of SHBG (p=0.01) and FSH (p=0.05). We found no association between the serum PCB concentration and the semen quality variables.

CONCLUSION

In this population of highly exposed fertile men, the current serum-PCB concentration was associated with higher androgen/estrogen ratio. Further studies are needed to establish the findings and further document PCB-associated hormonal effects, any time windows of increased susceptibility, and the role of PCB in sub-fecundity.

Prenatal phthalate exposures and anogenital distance in Swedish boys

BACKGROUND

Phthalates are used as plasticizers in soft polyvinyl chloride (PVC) and in a large number of consumer products. Because of reported health risks, diisononyl phthalate (DiNP) has been introduced as a replacement for di(2-ethylhexyl) phthalate (DEHP) in soft PVC. This raises concerns because animal data suggest that DiNP may have antiandrogenic properties similar to those of DEHP. The anogenital distance (AGD)--the distance from the anus to the genitals--has been used to assess reproductive toxicity.

OBJECTIVE

The objective of this study was to examine the associations between prenatal phthalate exposure and AGD in Swedish infants.

METHODS

AGD was measured in 196 boys at 21 months of age, and first-trimester urine was analyzed for 10 phthalate metabolites of DEP (diethyl phthalate), DBP (dibutyl phthalate), DEHP, BBzP (benzylbutyl phthalate), as well as DiNP and creatinine. Data on covariates were collected by questionnaires.

RESULTS

The most significant associations were found between the shorter of two AGD measures (anoscrotal distance; AGDas) and DiNP metabolites and strongest for oh-MMeOP [mono-(4-methyl-7-hydroxyloctyl) phthalate] and oxo-MMeOP [mono-(2-ethyl-5-oxohexyl) phthalate]. However, the AGDas reduction was small (4%) in relation to more than an interquartile range increase in DiNP exposure.

CONCLUSIONS

These findings call into question the safety of substituting DiNP for DEHP in soft PVC, particularly because a shorter male AGD has been shown to relate to male genital birth defects in children and impaired reproductive function in adult males and the fact that human levels of DiNP are increasing globally.

Associations between Exposure to Persistent Organic Pollutants in Childhood and Overweight up to 12 Years Later in a Low Exposed Danish Population

BACKGROUND

Persistent organic pollutants (POPs) have metabolic disrupting abilities and are suggested to contribute to the obesity epidemic. We investigated whether serum concentrations of POPs at 8-10 years of age were associated with subsequent development of overweight at age 14-16 and 20-22 years.

METHODS

The study was based on data from the European Youth Heart Study, Danish component (1997). Concentrations of several polychlorinated biphenyls (PCBs) and the organochlorine pesticides p,p-dichlorodiphenyldichloroethylene (DDE) and hexachlorobenzene (HCB) were measured in serum from children aged 8-10 years (n = 509). Information on BMI z-scores, waist circumference and % body fat were collected at clinical examinations at ages 8-10, 14-16 and 20-22 years. Multiple linear regression analyses were performed taking potential confounders into account.

RESULTS

Overall, POP serum concentrations were low: median ΣPCB 0.18 µg/g lipid, DDE 0.04 µg/g lipid and HCB 0.03 µg/g lipid. POPs were generally not associated with weight gain at 14-16 and 20-22 years of age, except for an inverse association among the highest exposed girls at 20-22 years of age, which might possibly be explained by multiple testing or residual confounding.

CONCLUSION

This study suggests that, in a low exposed population, childhood serum concentrations of PCB, DDE, and HCB are not associated with subsequent weight gain.

Polychlorinated biphenyl exposure and glucose metabolism in 9-year-old Danish children

CONTEXT

Human exposure to polychlorinated biphenyls (PCBs) has been associated to type 2 diabetes in adults.

OBJECTIVE

We aimed to determine whether concurrent plasma PCB concentration was associated with markers of glucose metabolism in healthy children.

SETTING AND DESIGN

Cross-sectional study of 771 healthy Danish third grade school children ages 8-10 years in the municipality of Odense were recruited in 1997 through a two-stage cluster sampling from 25 schools stratified according to location and socioeconomic character; 509 (9.7 ± 0.8 y, 53% girls) had adequate amounts available for PCB analyses.

OUTCOME MEASURES

Fasting serum glucose and insulin were measured and a homeostasis assessment model of insulin resistance (HOMA-IR) and β-cell function (HOMA-B) calculated. Plasma PCB congeners and other persistent compounds were measured and ΣPCB calculated.

RESULTS

PCBs were present in plasma at low concentrations, median, 0.19 μg/g lipid (interquartile range, 0.12-0.31). After adjustment for putative confounding factors, the second, third, fourth, and fifth quintiles of total PCB were significantly inversely associated with serum insulin (-14.6%, -21.7%, -18.9%, -23.1%, P trend < .01), compared with the first quintile, but not with serum glucose (P = .45). HOMA-IR and HOMA-B were affected in the same direction due to the declining insulin levels with increasing PCB exposure. Similar results were found for individual PCB congeners, for βHCB (hexachlorobenzen) and pp-DDE (dichlorodiphenyldichloroethylene).

CONCLUSIONS

A strong inverse association between serum insulin and PCB exposure was found while fasting glucose remained within the expected narrow range. Our findings suggest that PCB may not exert effect through decreased peripheral insulin sensitivity, as seen in obese and low-fit children, but rather through a toxicity to β-cells. It remains to be demonstrated whether lower HOMA-B is caused by destruction of β-cell-reducing peripheral insulin resistance and thereby increase fasting glucose as previously found.

Possible fetal determinants of male infertility

Although common reproductive problems, such as male infertility and testicular cancer, present in adult life, strong evidence exists that these reproductive disorders might have a fetal origin. The evidence is derived not only from large epidemiological studies that show birth-cohort effects with regard to testicular cancer, levels of testosterone and semen quality, but also from histopathological observations. Many infertile men have histological signs of testicular dysgenesis, including Sertoli-cell-only tubules, immature undifferentiated Sertoli cells, microliths and Leydig cell nodules. The most severe gonadal symptoms occur in patients with disorders of sexual development (DSDs) who have genetic mutations, in whom even sex reversal of individuals with a 46,XY DSD can occur. However, patients with severe DSDs might represent only a small proportion of DSD cases, with milder forms of testicular dysgenesis potentially induced by exposure to environmental and lifestyle factors. Interestingly, maternal smoking during pregnancy has a stronger effect on spermatogenesis than a man's own smoking. Other lifestyle factors such as alcohol consumption and obesity might also have a role. However, increasing indirect evidence exists that exposure to ubiquitous endocrine disrupting chemicals, present at measurable concentrations in individuals, might affect development of human fetal testis. If confirmed, health policies to prevent male reproductive problems should not only target adult men, but also pregnant women and their children.