Maternal reproductive and demographic characteristics as risk factors for hypospadias

Pregnancy and delivery in an advanced cancer survivor with immune checkpoint inhibitor-induced type 1 diabetes: a case report

PURPOSE

Given the rarity and elderly onset of immune checkpoint inhibitor (ICI)-induced type 1 diabetes (ICI-T1DM), cases leading to delivery are rare.

METHOD

To our knowledge, this is the first case report of childbirth in a patient with ICI-T1DM after cancer survival. A 32-year-old woman was started on Nivolumab for metastatic parotid cancers one year after total parotidectomy.

RESULT

The patient developed ICI-T1DM after 43 cycles and started multiple daily insulin therapy and self-monitoring of blood glucose. Complete response was maintained for 2 years by nivolumab, and she finished nivolumab in 77 cycles to attempt pregnancy. During the follow-up period, she began using a sensor-augmented pump (SAP). She had undetectable serum and urinary C-peptide when she started SAP. Her HbA1c level decreased from 7.8 to 6.6% without increasing hypoglycemia in one year. The patient remained in complete response after ICI discontinuation, and embryo transfer was initiated. Pregnancy was confirmed after a second embryo transfer (21 months after ICI discontinuation). At 36 weeks and 6 days, an emergency cesarean section was performed due to the onset of preeclampsia. The baby had hypospadias and bifid scrotum but no other complications or neonatal intensive care unit admission.

CONCLUSION

Because ICI discontinuation and ICI-T1DM carry risks for the patient and child, the decision regarding pregnancy warrants careful consideration. Diabetologists should collaborate with patients and other clinical departments to develop a treatment plan for childbirth.

Maternal PM2.5 exposure and hypospadias risk in Chinese offspring: Insights from a nationwide surveillance-based study

Research on the association between maternal PM2.5 exposure and hypospadias risk in male offspring, particularly in highly polluted areas, has been limited and inconsistent. This study leveraged data from China's National Population-based Birth Defects Surveillance System spanning the years 2013 to 2019, and employed sophisticated machine learning models to estimate daily PM2.5 levels and other pollutants for mothers at a 1-km resolution and a 6-km buffer surrounding maternal residences. Multivariate logistic regression analyses were performed to evaluate the relationship between PM2.5 exposure and hypospadias risk. For sensitivity analyses, stratification analysis was conducted, and models for one-pollutant and two-pollutants, as well as distributed lag nonlinear models, were constructed. Of the 1194,431 boys studied, 1153 cases of hypospadias were identified. A 10 μg/m3 increase in maternal PM2.5 exposure during preconception and the first trimester was associated with an elevated risk of isolated hypospadias, with Odds Ratios (ORs) of 1.102 (95% CI: 1.023-1.188) and 1.089 (95% CI: 1.007-1.177) at the 1-km grid, and 1.122 (95% CI: 1.034-1.218) and 1.143 (95% CI: 1.048-1.246) within the 6-km buffer. Higher quartiles of PM2.5 exposure were associated with increased odds ratios compared to the lowest quartile. These findings highlight a significant association between PM2.5 exposure during the critical conception period and an elevated risk of isolated hypospadias in children, emphasizing the need for targeted interventions to reduce PM2.5 exposure among expectant mothers.

Meconium Concentrations of Pesticides and Risk of Hypospadias: A Case-Control Study in Brittany, France

BACKGROUND

Hypospadias is a male genital tract defect for which an increase in prevalence has been documented over the last few decades. A role for environmental risk factors is suspected, including prenatal exposure to pesticides.

OBJECTIVES

To study the risk of hypospadias in association with multiple pesticide measurements in meconium samples.

METHODS

The Brittany Registry of Congenital Anomalies (France) conducted a case-control study between 2012 and 2018. Cases were hypospadias, ascertained by a pediatrician and a pediatric surgeon, excluding genetic conditions, following European Surveillance of Congenital Anomalies guidelines (N = 69). Controls (N = 135) were two male infants without congenital anomaly born after each case in the same maternity unit. Mothers in the maternity units completed a self-administered questionnaire, we collected medical data from hospital records, and medical staff collected meconium samples. We performed chemical analysis of 38 pesticides (parent compound and/or metabolite) by UHPLC/MS/MS following strict quality assurance/quality control criteria and blind to case-control status. We carried out logistic regression accounting for frequency-matching variables and major risk factors.

RESULTS

Among the 38 pesticides measured, 16 (42%) were never detected in the meconium samples, 18 (47%) were in <5% of samples, and 4 (11%) in ≥5% of the samples. We observed an association between the detection of fenitrothion in meconium and the risk of hypospadias (OR = 2.6 [1.0-6.3] with n cases = 13, n controls = 21), but not the other pesticides.

CONCLUSIONS

Our small study provides a robust assessment of fetal exposure. Fenitrothion's established antiandrogenic activities provide biologic plausibility for our observations. Further studies are needed to confirm this hypothesis.

An epidemiologic study of penoscrotal transposition by maternal characteristics using data from the Texas birth defects registry

BACKGROUND

Penoscrotal transposition (PST) is an uncommon urogenital malformation in which the penis is mal-positioned to be inferior to the scrotum. The purpose of this study was to explore PST risk by maternal characteristics and to describe co-occurring congenital abnormalities in the Texas Birth Defects Registry (TBDR).

METHODS

We conducted a population-based descriptive study examining occurrence of PST in the TBDR between 1999 and 2019. The primary outcome variable was PST diagnosis during infancy. Descriptive variables included maternal age, education, and race/ethnicity. Prevalence ratios (PRs) were calculated within each maternal variable category using Poisson regression. Counts and percentages of cases with select co-occurring congenital abnormalities were also calculated.

RESULTS

Overall, 251 infants had PST, providing a prevalence of 0.61/10,000 live male births (95% CI: 0.53-0.68). PST prevalence was significantly lower among infants of mothers who had lower educational attainment (high school), who were younger (<25 vs. 25-34), and who were Hispanic (vs. non-Hispanic White) and was significantly higher among older mothers (35+ vs. 25-39). Hypospadias was the most common co-occurring genitourinary anomaly, affecting close to 70% of cases.

CONCLUSIONS

To our knowledge, this is the first investigation exploring the prevalence of PST in a population-based birth defects registry. Our findings help to understand the risk for PST among select maternal demographic characteristics and may assist in generating hypotheses about the underlying etiology of this condition for future work.

Endocrine disrupting chemicals and their effects on the reproductive health in men

Endocrine Disrupting Chemicals (EDCs) are harmful compounds that enter the environment naturally or through anthropogenic activities and disrupt normal endocrine functions in humans, adversely affecting reproductive health. Among the most significant sources of EDC contaminants are the pharmaceutical, cosmetic, and packaging industries. EDCs have been identified to have a deteriorating effect on male reproductive system, as evidenced by the increasing number of male infertility cases. A large number of case studies have been published in which men exposed to EDCs experienced testicular cancer, undescended testicles, a decrease in serum testosterone levels, and poor semen quality. Furthermore, epidemiological evidence suggested a link between prenatal EDC exposure and cryptorchidism or undescended testicles, hypospadias, and decreased anogenital distance in infants. The majority of these findings, however, are incongruent due to the lack of long-term follow-up studies that would demonstrate EDCs to be associated with male reproductive disorders. This review aims to provide an overview on recent scientific progress on the association of EDCs to male reproductive health with special emphasis on its toxicity and possible mechanism of EDCs that disrupt male reproductive system.

The effect of the use of postoperative antibiotic prophylaxis compared with non-use for stented distal hypospadias repair wound: A meta-analysis

A meta-analysis investigation to measure the influence of the usage of postoperative antibiotic prophylaxis (POP) compared with non-usage for stented distal hypospadias repair (SDHR). A comprehensive literature inspection till February 2023 was applied and 1067 interrelated investigations were reviewed. The 10 chosen investigations enclosed 1398 individuals with SDHR in the chosen investigations starting point, 812 of them were using POP, and 586 were not using POP. Odds ratio (OR) in addition to 95% confidence intervals (CIs) were used to compute the value of the effect of the usage of POP compared with non-usage for SDHR by the dichotomous and continuous approaches and a fixed or random model. No significant difference was found between individuals using POP and not using POP in posthypospadias repair problem (PRP) (OR, 0.99; 95% CI, 0.42-2.34, P = .97) with moderate heterogeneity (I2  = 69%), posthypospadias repair infection problem (PRIP) (OR, 0.56; 95% CI, 0.30-1.06, P = .08) with no heterogeneity (I2  = 15%), and overall composite posthypospadias repair wound healing associated problem (OCPRWHAP) (OR, 1.27; 95% CI, 0.61-2.63, P = .53) with moderate heterogeneity (I2  = 59%) for SDHR. No significant difference was found between individuals using POP and not using POP in PRP, PRIP, and OCPRWHAP for SDHR. However, cautilised of the small sample sizes of several chosen investigations for this meta-analysis, care must be exercised when dealing with its values, for example, the low P-value of the PRIP.

Identification of a novel candidate HSD3B2 gene variant for familial hypospadias by whole-exome sequencing

Introduction: Hypospadias [MIM: 300633] is one of the most frequent congenital malformations of male external genitalia. The spectrum of genetic variants causing hypospadias is varied, with studies commonly implicating genes critical in the fetal steroidogenic pathway. This is the first genetic study on hypospadias from the Yemen ethnicity and the second to report HSD3B2 mutations in more than one affected individual from the same family. Material and methods: Surgical hypospadias repair was performed on two hypospadias-affected siblings from a consanguineous family. Whole-exome sequencing (WES) was performed to identify the potential pathogenic variant for hypospadias, which was later confirmed by Sanger sequencing. The identified variant was further analyzed for its pathogenicity by using in silico tools such as SIFT, PolyPhen-2, MutationAssessor, MutationTaster, FATHMM, and ConSurf. Results: We identified a novel missense mutation (Chr1:119964631T>A, c.507T>A, p. N169K) in 3β-hydroxysteroid 2-dehydrogenase (HSD3B2) gene by WES. Sanger sequencing confirmed that the variant segregated the disease in the family between the affected and non-affected individuals. Both patients are homozygous, while parents and two unaffected siblings are heterozygous carriers, indicating an autosomal recessive pattern of inheritance. The in silico analysis by all six in silico tools (SIFT, PolyPhen-2, MutationAssessor, MutationTaster, FATHMM, and ConSurf) predicted the variant to be pathogenic/deleterious. Discussion: An abnormal fetal steroidogenic pathway due to genetic influences may affect the development of the male genital tract, including the urethral tract closure and morphogenesis of male genitalia. Furthermore, the pathogenicity of the observed variant in this study, confirmed by multiple in silico tools, characterizes the influence HSD3B2 gene variants may have in the etiology of hypospadias. Conclusion: Understanding of pathogenic manifestation and inheritance of confounding genetic variants in hypospadias is a matter of great concern, especially in familial cases.

Maternal Cigarette Smoking During Pregnancy and Genital Anomalies in Boys: A Register-Based Cohort and Sibling-Matched Design Study

Purpose

Cryptorchidism and hypospadias share several prenatal risk factors. However, in published studies, boys exposed to cigarette smoking during pregnancy have a higher risk of cryptorchidism and a lower risk of hypospadias. Using Danish register-based data, we revisited these findings with a cohort and sibling-matched design to investigate the potential effect of shared time-stable factors.

Patients and Methods

For the cohort study, we included 823,670 live-born, singleton boys born from 1991 to 2016. Crude and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox regression models for each genital anomaly according to maternal cigarette smoking during pregnancy. For the sibling-matched design, we included 399,258 brothers and used a stratified Cox regression model creating family-adjusted results.

Results

In the cohort study, we found a higher risk of cryptorchidism (aHR = 1.18, 95% CI: 1.12, 1.24) and a lower risk of hypospadias (aHR = 0.84, 95% CI: 0.76, 0.93) when comparing boys exposed to cigarette smoking with non-exposed, and for increasing numbers of cigarettes smoked. In comparison, the sibling-matched analyses suggested a slightly weaker association for cryptorchidism and an association of similar magnitude for hypospadias, both in the same direction as in the cohort study.

Conclusion

Shared, familial confounding does not seem to explain earlier findings of higher risk of cryptorchidism and lower risk of hypospadias.

Prevalence and Clustering of Congenital Heart Defects Among Boys With Hypospadias

IMPORTANCE

Hypospadias is a common birth defect of the male urinary tract that may be isolated or may co-occur with other structural malformations, including congenital heart defects (CHDs). The risk for co-occurring CHDs among boys with hypospadias remains unknown, which limits screening and genetic testing strategies.

OBJECTIVE

To characterize the risk of major CHDs among boys born with hypospadias.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from population-based birth defect surveillance programs on all male infants born in 11 US states from January 1, 1995, to December 31, 2014. Statistical analysis was performed from September 2, 2020, to March 25, 2022.

EXPOSURE

Hypospadias.

MAIN OUTCOMES AND MEASURES

Demographic and diagnostic data were obtained from 2 active state-based birth defect surveillance programs for primary analyses, the Texas Birth Defects Registry and the Arkansas Reproductive Health Monitoring System, with validation among 9 additional states in the National Birth Defects Prevention Network (NBDPN). Birth defect diagnoses were identified using the British Pediatric Association coding for hypospadias (exposure) and major CHDs (primary outcomes). Maternal covariates and birth year were also abstracted from the vital records. Poisson regression was used to estimate adjusted prevalence ratios and 95% CIs for major CHDs within Texas and Arkansas and combined using inverse variance-weighted meta-analysis. Findings were validated using the NBDPN.

RESULTS

Among 3.7 million pregnancies in Texas and Arkansas, 1485 boys had hypospadias and a co-occurring CHD. Boys with hypospadias were 5.8 times (95% CI, 5.5-6.1) more likely to have a co-occurring CHD compared with boys without hypospadias. Associations were observed for every specific CHD analyzed among boys with hypospadias, occurred outside of chromosomal anomalies, and were validated in the NBDPN. An estimated 7.024% (95% CI, 7.020%-7.028%) of boys with hypospadias in Texas and 5.503% (95% CI, 5.495%-5.511%) of boys with hypospadias in Arkansas have a co-occurring CHD. In addition, hypospadias severity and maternal race and ethnicity were independently associated with the likelihood for hypospadias to co-occur with a CHD; boys in Texas with third-degree (ie, more severe) hypospadias were 2.7 times (95% CI, 2.2-3.4) more likely than boys with first-degree hypospadias to have a co-occurring CHD, with consistent estimates in Arkansas (odds ratio, 2.7; 95% CI, 1.4-5.3), and boys with hypospadias born to Hispanic mothers in Texas were 1.5 times (95% CI, 1.3-1.8) more likely to have a co-occurring CHD than boys with hypospadias born to non-Hispanic White mothers.

CONCLUSIONS AND RELEVANCE

In this cohort study, boys with hypospadias had a higher prevalence of CHDs than boys without hypospadias. These findings support the need for consideration of additional CHD screening programs for boys born with hypospadias.

Do in vitro fertilization, intrauterine insemination or female infertility impact the risk of congenital anomalies in singletons? A longitudinal national French study

STUDY QUESTION

Do IVF, IUI or female infertility (i.e. endometriosis, polycystic ovary syndrome [PCOS] and primary ovarian insufficiency [POI]) lead to an increased risk of congenital anomalies in singletons?

SUMMARY ANSWER

After multivariable adjustments, the increased risks of congenital defects associated with IUI were no longer significant, but the underlying maternal infertility presented a potential emental risk, in addition to the risk associated with IVF.

WHAT IS KNOWN ALREADY

Most epidemiological studies suggest that singletons born from ART have a higher risk of birth defects, specifically musculoskeletal, cardiovascular and urogenital disorders. However, most of these studies were established on data obtained at birth or in the neonatal period and from relatively small populations or several registries. Moreover, to our knowledge, female infertility, which is a potential confounder, has never been included in the risk assessment.

STUDY DESIGN, SIZE, DURATION

Using data from the French National Health System database, we conducted a comparative analysis of all singleton births (deliveries ≥22 weeks of gestation and/or >500 g of birthweight) in France over a 5-year period (2013-2017) resulting from fresh embryo or frozen embryo transfer (fresh-ET or FET from IVF/ICSI cycles), IUI and natural conception (NC). Data were available for this cohort of children at least up to early childhood (2.5 years old).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 3 501 495 singleton births were included (3 417 089 from NC, 20 218 from IUI, 45 303 from fresh-ET and 18 885 from FET). Data were extracted from national health databases and used to identify major birth defects. Malformations were classified according to the 10th revision of the International Classification of Disease. To analyse the effect of mode of conception, multivariable analyses were performed with multiple logistic regression models adjusted for maternal age, primiparity, obesity, smoking, history of high blood pressure or diabetes and female infertility.

MAIN RESULTS AND THE ROLE OF CHANCE

In our cohort of children, the overall prevalence of congenital malformations was 3.78% after NC, 4.53% after fresh-ET, 4.39% after FET and 3.91% after IUI (132 646 children with major malformations). Compared with infants conceived naturally, children born after fresh-ET and after FET had a significantly higher prevalence of malformations, with an adjusted odds ratio (aOR) of 1.15 [95% CI 1.10-1.20, P < 0.0001] and aOR of 1.13 [95% CI 1.05-1.21, P = 0.001], respectively. Among the 15 relevant subgroups of malformations studied, we observed a significantly increased risk of eight malformations in the fresh-ET group compared with the NC group (i.e. musculoskeletal, cardiac, urinary, digestive, neurological, cleft lip and/or palate and respiratory). In the FET group, this increased risk was observed for digestive and facial malformations. The overall risk of congenital malformations, and the risk by subtype, was similar in the IUI group and the NC group (overall risk: aOR of 1.01 [95% CI 0.94-1.08, P = 0.81]). In addition, there was an overall independent increase in the risk of congenital defects when the mothers were diagnosed with endometriosis (1.16 aOR [95% CI 1.10-1.22], P < 0.0001), PCOS (1.20 aOR [95% CI 1.08-1.34], P = 0.001) or POI (1.52 aOR [95% CI 1.23-1.88], P = 0.0001). Chromosomal, cardiac and neurological anomalies were more common in the three maternal infertility groups.

LIMITATIONS, REASONS FOR CAUTION

Male infertility, the in vitro fertilization method (i.e. in vitro fertilization without or with sperm injection: conventional IVF vs ICSI) and embryo stage at transfer could not be taken into account. Furthermore, residual confounding cannot be excluded as well as uncertainties regarding the diagnostic criteria used for the three female infertilities. Findings for specific malformations should be interpreted with caution because the number of cases was small in some sub-groups (potentially due to the Type I error or multiple testing).

WIDER IMPLICATIONS OF THE FINDINGS

In this large study, after multivariable maternal adjustments, a moderately increased risk of defects subsisted after IVF, while those associated with IUI were no longer significant. In addition, our results showed that underlying maternal infertility could contribute to the increased risk of defects associated with IVF. These novel findings highlight the importance of taking into account the ART treatment methods and the type of infertility.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Agency of Biomedicine. The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

NA.

Patterns of co-occurring birth defects among infants with hypospadias

INTRODUCTION

Hypospadias, one of the most common male genital birth defects, occurs in 1 out of every 200 male births in the United States and is increasing in prevalence globally.

OBJECTIVE

This study aimed to characterize the combinations of birth defects that co-occur with hypospadias more often than expected by chance, while accounting for the complex clustering patterns of congenital defects.

STUDY DESIGN

We analyzed cases with hypospadias and at least one additional co-occurring defect from the Texas Birth Defect Registry born between 1999 and 2014. For each combination, we calculated adjusted observed-to-expected (O/E) ratios, using Co-Occurring Defect Analysis (CODA).

RESULTS

Among 16,442 cases with hypospadias and without known syndromes, 2,084 (12.7%) had at least one additional defect. Many of the birth defect combinations within the highest adjusted O/E ratios included cardiac, musculoskeletal, and additional urogenital defects. For example, a top combination with an adjusted O/E of 139.0 included renal agenesis and dysgenesis, reduction defects of the upper limb, and other anomalies of upper limb (including shoulder girdle). High adjusted O/E ratios were also observed in combinations that included defects outside of the urogenital developmental field. For instance, the combination with the highest O/E ratio included buphthalmos, and congenital cataract and lens anomalies (adjusted O/E ratio: 192.9). Similar results were obtained when we restricted our analyses to cases with second- or third-degree hypospadias.

DISCUSSION

Many combinations in the top results were expected (e.g., multiple urogenital defects); however, some combinations with seemingly unrelated patterns of defects may suggest the presence of some etiologic mechanisms yet to be identified.

CONCLUSION

In summary, this study described patterns of co-occurring defect combinations with hypospadias that can inform further study and may provide insights for screening and diagnostic practices.

Hypospadias prevalence in the Emilia Romagna Region registry: Increasing or methodology?

INTRODUCTION

Hypospadias is one of the most common congenital anomalies in male infants, defined as incomplete development of the urethra. Despite the wealth of literature, there are conflicting data on the values and trends of prevalence, due to multifactorial origin but often also to methodological differences between studies. The aim of this study was to analyse prevalence, trends and risk factors of hypospadias in the Emilia Romagna Region, Italy.

MATERIAL AND METHODS

The Emilia-Romagna Registry (IMER) is a population-based congenital anomaly database covering the first year of life, active since 1978. IMER uses multi-source ascertainment, including hospital discharge records (SDO) from 2009, through a validated algorithm. From 2014, IMER changed the algorithm, and included all hypospadias identified in SDO, and not only those confirmed by surgery. All cases identified in the IMER database, coded 7526.01-7526.09 or Q54.0-Q54.9 in 2010-2016, were analysed.

RESULT AND DISCUSSION

A total of 604 hypospadias cases were registered among 267,285 births; 526 were isolated, giving a prevalence of 2 per 1000. An increase from 1.6 in 2010 to 2.9 in 2016 was seen. The comparison between consecutive years was not significant neither from 2010 to 2013 nor in the period 2014-2016. There was instead a significant difference between the two periods, suggesting that the ascertainment change in 2014 is probably responsible for the increase. In the last three years analysed, isolated hypospadias prevalence is 2.5 per 1000. In the study period, mother's age over 39 years, multiple birth, preterm birth, small for gestational age, Caucasian compared with Asiatic or Africans were statistically associated with higher hypospadias prevalence. There was no association neither between hypospadias and paternal age nor maternal body mass index or assisted reproductive technology.

CONCLUSION

Whilst hypospadias prevalence trend is debated in the literature, in IMER it seems to be stable, with methodological changes affecting the trends. Risk factors potentially involved in developing hypospadias are environment and population characteristics, so understanding and monitoring hypospadias prevalence remains important.

The use of postoperative prophylactic antibiotics in stented distal hypospadias repair: a systematic review and meta-analysis

INTRODUCTION

The current literature on the use of antibiotics perioperatively for many pediatric procedures, including hypospadias, is inconsistent. There is currently no clear evidence for the use of postoperative antibiotic prophylaxis for stented distal hypospadias repair.

OBJECTIVE

This study aims to synthesize and assess the available literature on the use versus non-use of postoperative antibiotic prophylaxis for stented distal hypospadias repair.

METHODOLOGY

Systematic literature search was performed on March 2018 for evaluation of trials that assessed the use and non-use of postoperative prophylactic antibiotics among stented distal hypospadias repair in children. Methodological quality of the studies was assessed according to the study design as recommended by the Cochrane Collaboration. The outcome assessed includes composite overall posthypospadias repair complications of infection and wound healing complications. The event rate for each treatment group was extracted to extrapolate intervention relative risk (RR) and corresponding 95% confidence interval (CI). Mantel-Haenszel method with random effect model was used in pooling of effect estimates from the included studies. Heterogeneity was assessed with subgroup analysis performed according to the study design. Publication bias was likewise determined. The protocol of this review was registered in PROSPERO (CRD42018087301) and reported in accordance with preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines.

RESULT

A total of seven studies (four cohorts, three randomized controlled trials) with 986 stented distal hypospadias repairs (408 with no post-operative prophylactic antibiotics and 578 given postoperative prophylactic antibiotics) were included for the meta-analysis. Moderate to serious risk of bias was noted among the cohort studies, while the included randomized controlled trials (RCT) were of high risk of bias. Inconsistencies of effect estimates between subgroups and publication bias with small study effect were likely present. The overall pooled effect estimates comparing treatment groups showed no significant difference for outcomes of overall composite postoperative complication (RR 0.93, 95% CI 0.45, 1.93). Assessment of composite infection related complications and wound healing complications likewise did not show any significant between-group differences (RR 1.28, 95% CI 0.49, 3.35 and RR 1.01, 95% CI 0.48, 2.12; respectively) (Table). Asymptomatic bacteriuria was noted to be significantly higher among the intervention group with no postoperative prophylactic antibiotics (RR 4.01, 95% CI 1.11, 14.54).

CONCLUSION

The available evidence to date was assessed to be of high risk. The low level of evidence generated suggests that there is limited utility in the use of postoperative prophylactic antibiotics to prevent clinically significant posthypospadias repair complications.

Parental subfertility and hypospadias and cryptorchidism in boys: results from two Danish birth cohorts

OBJECTIVE

To study if parental subfertility is related to the occurrence of the male genital anomalies, cryptorchidism and hypospadias.

DESIGN

Population-based cohort study.

SETTING

Not applicable.

PATIENT(S)

A total of 80,220 singleton boys and their mothers from the Danish National Birth Cohort and the Aarhus Birth Cohort.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The two congenital anomalies; cryptorchidism and hypospadias, registered within the Danish National Patient Register up until December 31, 2012.

RESULT(S)

By means of Cox regression analyses, we found no associations between waiting time-to-pregnancy (TTP) and cryptorchidism or hypospadias among those who conceived spontaneously. The highest hazard ratio for cryptorchidism was seen among boys of couples with a TTP>12 months who conceived after fertility treatment (adjusted hazard ratio [aHR] 1.19, 95% confidence interval 0.92-1.55). For hypospadias, we found that boys of couples with a TTP>12 months who conceived after fertility treatment, had a 71% higher risk of hypospadias (aHR 1.71, [95% confidence interval 1.24-3.36]) as compared with boys of couples with a TTP<5 months.

CONCLUSION(S)

The findings from this study showed that boys of couples with TTP>12 months who conceived after fertility treatment, had a higher occurrence of hypospadias than boys conceived spontaneously of couples with a short TTP. Among those who conceived spontaneously, TTP was not associated with hypospadias or cryptorchidism. These findings indicate that fertility treatment or severity of subfertility is related to hypospadias.

A retrospective population-based cohort study to evaluate the impact of an older sibling with undescended testis and hypospadias on the known maternal and fetal risk factors for undescended testis and hypospadias in Ontario, Canada, 1997-2007

INTRODUCTION

There are several reported risk factors for undescended testis (UDT) and hypospadias (HYP). Also, a family history of UDT or HYP has not been accounted for in prior studies, and doing so may influence these independent risk estimates.

STUDY DESIGN

A population-based retrospective cohort study was conducted using linked administrative databases in Ontario, Canada, to identify all live male newborns born between 1997 and 2007, and it was determined whether they underwent an orchidopexy or HYP repair within 5 years of birth. Baseline maternal and fetal risk factors were obtained using appropriate ICD codes. A statistical analysis using a generalized estimating equation with a logit link was performed, adjusting for clustering in mothers with a previous child born in the 5 years before the proband with UDT or HYP, to evaluate the adjusted risk factors of UDT and HYP.

RESULTS

A total of 709,968 male infants were followed up from birth for 5 years, of which 5830 underwent an orchidopexy and 2722 had an HYP repair. On multivariable analysis, factors associated with a higher risk of UDT included prematurity, small for gestational age (SGA), associated HYP, gestational hypertension, use of assisted fertility techniques, increased maternal age, Cesarean section, previous sibling with UDT, and disorders of sexual differentiation (DSDs). After adjusting for clustering in mothers with a previous baby with UDT, DSD, associated HYP (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.0-4.1), and a previous sibling with UDT (OR, 3.6; 95% CI, 2.5-5.2) remained significant risk factors. The risk factors on multivariable analysis predicting the risk of HYP included SGA, prematurity, higher income families, and associated anomalies such as UDT. After adjusting for clustering in mothers with a previous sibling with HYP, SGA (OR, 1.8; 95% CI, 1.0-3.1), higher income families (OR, 1.5-1.6), associated UDT (OR, 7.1; 95% CI, 4.9-10.0), and a previous sibling with HYP (OR, 12.8; 95% CI, 9.1-18.1) remained significant risk factors.

DISCUSSION

Studies estimating risk factors for UDT and HYP have used variable methodologies to identify index cases and perform statistical analysis. This study suggests that having an older sibling with UDT or HYP is a significant independent risk factor. Performing an analysis adjusting for clustering in mothers with a previous child with UDT or HYP leads to loss of statistical significance for other described risk factors.

CONCLUSION

Underlying genetic or similar environmental exposures may be a key risk factor for UDT and HYP, which confounds known maternal and fetal risk factors for these anomalies.

Impact of changes in human reproduction on the incidence of endocrine-related diseases

The incidence rates of a wide range of diseases and conditions have increased over the last decades. There is controversy over the origin of these increases, whether they are caused by exposure to compounds thought to have an effect on the endocrine system, the "endocrine disruption theory", or whether some other factor is responsible. In this analysis, the authors take a closer look at the role that changes in reproductive factors have played in this respect. They apply the relative risks of age at first pregnancy and parity or family size to a set of Dutch demographic data from 1955 and 2015 and calculate the percentage of disease increase explained. The decrease in parity over the last decades explains an increase of 26% in testicular cancer. The combination of decrease in parity and increase in maternal age at first pregnancy explains an increase of 34% in hypospadias prevalence. This combination of decreased parity and increased maternal age at pregnancy explains an increase of 24% in childhood obesity prevalence. The authors further point to a perhaps even more profound effect of the trend toward smaller families. This trend has led to an estimated doubling of the proportion of children born from subfertile couples. Since children born from subfertile couples are more likely to be preterm or of low birth weight, the incidence of these conditions must have increased as well. Low birth weight and preterm delivery are risk factors for a wide range of diseases and conditions. The changes in human reproduction over the last decades have had a profound impact on the incidence of a range of diseases and conditions in the next generation and thus provide a sound explanation for a substantial portion of the reported increases. Key messages The incidence rates of a wide range of diseases and conditions have increased in the Western societies over the last decades. Many have argued that these increases are attributable to compounds thought to have effects on the human endocrine system: the endocrine disruption theory This analysis shows, however, that human reproductive factors such as maternal age at first pregnancy and parity explain substantial proportions of the reported increases.

The relationship between some neonatal and maternal factors during pregnancy with the prevalence of congenital malformations in Iran: a systematic review and meta-analysis

Introduction: Congenital malformations are one of the main causes of death and disability in children. These malformations arise during embryogenesis and fetal development during pregnancy due to exposure to some environmental factors and genetic mutations. Given the high prevalence of congenital malformations in Iran, the current study was conducted to investigate the relationship between some neonatal and maternal factors during pregnancy with the prevalence of congenital malformations in Iran. Methods: This was a systematic review and meta-analysis study. All studies conducted in Iran were extracted between 2000 and 2016 during a search in internal and external databases of Medlib, Medline, Pubmed, Web of Science, Google Scholar, Scopus, Magiran, SID, Cochrane, Irandoc, and all articles published. Then, the required data were entered into the Spss16 software (SPSS Inc., Chicago, IL); and the model of fixed and random effects was analyzed in meta-analysis, Cochran, meta-regression using statistical tests. Results: A total of 30 studies with a sample size of 928,311 patients were enrolled. Baby's gender (1-1.55: CI95%) OR: 1.25, preterm delivery (1.71-3.69: CI 95%) OR: 2.51, low birth weight (1.13-2.67: CI95%) OR: 1.74, age older than 35 for the pregnant mother (1.41-6.3: CI 95%) OR: 2.98, multiple births (1.14-3.46: CI 95%) OR: 1.99, mother suffering from chronic diseases (1.68-3.31: CI 95%) OR: 2.36 are significantly related with the risk of congenital malformations. Conclusion: Based on the results the baby's gender, premature birth, low birth weight, mother's age, consanguineous marriages, multiple births, family history of congenital malformations, and the risk of chronic diseases in the mother during pregnancy increase the birth of children with congenital malformations. As a result, control or modification of the above factors implementing a health and education intervention program can reduce the birth of children with congenital malformations.

Comparison of the Fagerström Test for Cigarette Dependence and the Heaviness of Smoking Index in the Second and Third Trimester of Pregnancy

Introduction

Smoking cessation at any stage of pregnancy can benefit the mother and fetus. Cigarette dependence is a significant factor in women who continue to smoke during pregnancy and accurate assessment of cigarette dependence can be helpful in planning smoking cessation programs. The objective of our study was to investigate the validity of the Fagerstrom Test for Cigarette Dependence (FTCD) and Heaviness of Smoking Index (HSI) as measures of cigarette dependence in the second and third trimesters of pregnancy by comparing them to serum cotinine levels.

Methods

Prospective cohort study of 167 women in their second and third trimester of pregnancy who self-reported cigarette smoking. They were administered the FTCD questionnaire and blood was drawn for cotinine measurements using a direct enzyme linked immunoassay. Linear regression was used to adjust for maternal age, body mass index, gestation, and parity to investigate the association between cotinine levels and the two scores.

Results

Both the FTCD and HSI correlated significantly with serum cotinine levels (Spearman coefficient 0.42 and 0.37, respectively, p < .001). The correlation coefficients of both scores were higher in primigravidas (n = 51) compared to multigravidas, but the difference was statistically nonsignificant. Using multiple linear regression, both scores were significantly related to serum cotinine levels. For each unit increase in the FTCD and HSI, the serum cotinine level increased by 21.4 ng/mL (95% confidence interval 10.1-32.7, p <0.001) and 37 ng/mL (95% confidence interval 18.6-55.4, p < 0.001), respectively.

Conclusions

Both the FTCD and HSI can be used to assess cigarette dependence in the second and third trimester of pregnancy.

Implications

There is lack of data on the validity of the FTCD and the HSI as markers of cigarette dependence during the second and third trimester of pregnancy. Our study suggests that both the FTCD and HSI perform well in assessing cigarette dependence in the second and third trimester of pregnancy and can be used to plan smoking cessation programs.

Maternal Overweight and Obesity and Genital Anomalies in Male Offspring: A Population-Based Swedish Cohort Study

BACKGROUND

Overweight and obese pregnant women face higher risk of several critical birth outcomes, including an overall increased risk of congenital abnormalities. Only few studies have focused on associations between maternal overweight and the genital anomalies in boys, cryptorchidism and hypospadias, and results are inconclusive.

METHODS

We performed a population-based cohort study and assessed the associations between maternal body mass index (BMI) in early pregnancy and occurrence of cryptorchidism and hypospadias. All live-born singleton boys born in Sweden from 1992 to 2012 were included. From the Swedish Patient Register, information on cryptorchidism and hypospadias was available. Data were analysed using Cox proportional hazards regression adjusted for potential confounders. Mediation analyses were performed to estimate how much of the association between BMI and genital anomalies were mediated through obesity-related diseases.

RESULTS

Of the 1 055 705 live-born singleton boys born from 1992 to 2012, 6807 (6.4 per 1000) were diagnosed with hypospadias and 16 469 (15.6 per 1000) were diagnosed with cryptorchidism, of which 9768 (9.3 per 1000) underwent corrective surgery for cryptorchidism. We observed dose-response associations between maternal BMI and hypospadias and cryptorchidism. Boys of mothers with BMI ≥40.0 kg/m² had the highest adjusted hazard ratios for hypospadias (HR 1.35, 95% confidence interval [CI] 1.04, 1.76) and cryptorchidism (HR 1.25, 95% CI 1.00, 1.58). A substantial proportion of the associations between BMI and the genital anomalies were mediated through preeclampsia.

CONCLUSION

This large register-based study adds to the current literature and indicates that the occurrence of hypospadias and cryptorchidism increase with maternal overweight and obesity severity.

Maternal hypertension and risk for hypospadias in offspring

Hypospadias is one of the most common birth defects in male infants. Maternal hypertension is a suspected risk factor; however, few previous studies have addressed the possibility of reporting bias, and several previous studies have not accounted for hypospadias severity. We analyzed data from the Texas Birth Defects Registry for 10,924 nonsyndromic cases and statewide vital records for deliveries during 1999-2009, using Poisson regression. After adjustment for potential confounders, hypospadias was associated with maternal hypertension (adjusted prevalence ratio: 1.5, 95% confidence interval: 1.4-1.7). Similar associations were observed with gestational and pregestational hypertension, including separate analyses restricted to the subset of cases with severe (second- or third-degree) hypospadias. All of these associations were also similar among the subset of cases with isolated hypospadias (without additional birth defects). To evaluate the potential for bias due to potential hypertension misclassification, we repeated our analyses using logistic regression, comparing the cases to controls with other birth defects. In these analyses, the associations with gestational hypertension were similar, but adjusted associations with pregestational hypertension were no longer observed. Our findings support an association between gestational hypertension and hypospadias in offspring, but also suggest that previously observed associations with pregestational hypertension may have been inflated due to differential misclassification of hypertension (e.g., reporting bias). As gestational hypertension is recognized after hypospadias development, more research is needed to determine if this association reflects an increase in gestational hypertension risk secondary to hypospadias or if both conditions have shared risk factors (e.g., precursors of gestational hypertension). © 2016 Wiley Periodicals, Inc.

Association between SNP12 in estrogen receptor α gene and hypospadias: a systematic review and meta-analysis

To investigate the association between single nucleotide polymorphism 12 in estrogen receptor α gene and hypospadias, four databases (PubMed, Web of Science, Embase and Cochrane Library) were electronically searched by 2nd November 2015. Finally, four studies were included for our meta-analysis, involving 1379 cases and 1648 controls. A quality assessment was performed using the Newcastle–Ottawa Scale of case–control study. Meta-analysis and publication bias measuring were all done by Stata 12.0. No significant publication bias (P_Begg = 0.296, P_Egger = 0.161) was found. Overall, there was statistically significant association for recessive genetic model (AA vs. GA + GG: OR 3.45, 95 % CI [1.89, 6.30], P = 0.038). Moreover, the positive result was confirmed using trial sequential analysis even only three original studies. For allele model, there was also statistically significant association (allele A vs. G: OR 1.43, 95 % CI [1.23, 1.67], P = 0.034). Meanwhile, A allele as a risk factor turned out to be true positive by trial sequential analysis. In a word, this meta-analysis suggested that the single nucleotide polymorphism 12 definitely increase the risk of hypospadias.

Maternal obesity and the risk of neural tube defects in offspring: A meta-analysis

OBJECTIVES

The aim of this was to access maternal obesity and the risk of neural tube defects (NTDs) in offspring, and establishes a nonlinear dose-response relationship between maternal body mass index (BMI) and risk of NTDs in offspring.

METHODS

PubMed and Web of Science were systematically searched. We compared NTDs risk difference in maternal obesity group vs. normal weight group+overweight group, and maternal obesity group vs. normal weight group. We also examined the dose-response relationship between maternal body mass index and the risk of NTDs in offspring.

RESULTS

A total of 22 studies with 1,758,832 patients included in the meta-analysis. The results showed obesity maternal obesity is an important risk factor for NTDs in offspring. When maternal obesity group compared with normal weight group+overweight group, the summary OR of NTDs was 1.632 (95% CI 1.473-1.808; Z=9.37, P<0.00001); when maternal obesity group compared with normal weight group, the summary OR was 1.682 (95% CI 1.510-1.873; Z=9.44, P<0.00001). No publication biases were found. Dose-response meta-analysis showed statistically significant association between maternal BMI and risk of NTDs in offspring (model χ²=41.49, <0.00001). In linear model, the OR of NTDs in offspring was 1.040 (95% CI 1.027-1.051) for every 1kg/m² BMI increase in mother. In spline model, the OR of NTDs in offspring risk increased rapidly along with maternal BMI, especially when BMI >30kg/m². Sensitivity analyses by only included the studies reported adjusted OR showed the result was robust.

CONCLUSION

Our meta-analysis indicated that maternal obesity is an important risk factor for neural tube defects in offspring.

The association between maternal parity and birth defects

BACKGROUND

Previous studies observed that first birth is associated with an increased risk of some categories of birth defects. However, multiple statistical tests were conducted and it was unclear which of these associations would be replicated in a larger study. We used a large database to assess the association between maternal parity and 65 birth defects including birth defects that have not been previously studied.

METHODS

Using data from the Texas Birth Defects Registry for years 1999-2009, the risk of a birth defect occurring in a first, third, or fourth or higher birth was compared to the risk of a birth defect occurring in a second birth.

RESULTS

Women having their first birth had significantly increased odds of having an infant with 24 of 65 categories of birth defects when compared to women having their second birth. We also observed associations between first birth and an increased risk of five birth defects not previously reported (small penis, preaxial polydactyly, anomalies of the thoracic vertebrae, anomalies of the lumbar vertebrae, and sacroccygeal anomalies). Women having their third or fourth or higher birth had significantly increased odds of giving birth to infants with five of 65 birth defects when compared to second births.

CONCLUSIONS

Our observations regarding the categories of birth defects that were associated with first births were highly consistent with observations from two previous studies. Research into biological, behavioral, and environmental factors that may increase the risk of specific birth defects among first births is needed to further explore these associations.

Maternal exposures in the National Birth Defects Prevention Study: Time trends of selected exposures

BACKGROUND

Our objective was to describe time trends in selected pregnancy exposures in the National Birth Defects Prevention Study (NBDPS).

METHODS

We analyzed data from the NBDPS, a multi-site case-control study of major birth defects, for mothers of live-born infants without birth defects (controls), with an expected date of delivery (EDD) from 1998 to 2011. Mothers from the 10 participating centers across the United States were interviewed by phone between 6 weeks and 2 years after the EDD. We focused on maternal race/ethnicity and five maternal risk factors: obesity, use of folic acid-containing multivitamins, opioid analgesics, selective serotonin reuptake inhibitors, and loratadine because of their prevalence of use and some reports of associations with major birth defects. Prevalence time trends were examined using the Kendall's τβ test statistic.

RESULTS

The exposure trend analysis included 11,724 control mothers with EDDs from 1998 to 2011. We observed a significant increase in obesity prevalence among control mothers, as well as use of selective serotonin reuptake inhibitors and loratadine. We also observed an increase in periconceptional use of folic acid-containing multivitamins. Some of the time trends varied by race/ethnicity. No remarkable trend in the overall use of opioid analgesics was observed. The racial/ethnic distribution of mothers changed slightly during the study period.

CONCLUSION

Long-term, population-based case-control studies continue to be an effective way to assess exposure-birth defects associations and provide guidance to health care providers. However, investigators examining rare outcomes covering many years of data collection need to be cognizant of time trends in exposures.

Risk factors for hypospadias in China

This case-controlled study was designed to evaluate the association between various baseline parental factors and the risk of hypospadias in China. Patients were selected from tertiary referral hospitals in Anhui, a province in mid-eastern China. A questionnaire was given to the parents of each patient. The final database included 193 cases and 835 controls. The incidence of additional coexistent anomalies was 13.0%, primarily cryptorchidism (9.8%). Ten patients (5.1%) were from families with genital anomaly, including five families (2.6%) with hypospadias. The risks of hypospadias was higher for children of mothers > 35 (odds ratio [OR] =1.47) and < 18 (OR = 2.95) years of age, and in mothers who had consumed alcohol (OR = 2.67), used drugs (OR = 1.53) and had an infection (OR = 1.87) during pregnancy. The risk of hypospadias was also higher when mothers (OR = 1.68) and fathers (OR = 1.74) were engaged in agriculture. Other factors assessed were not associated with the risk of hypospadias.

Genetic and environmental factors in the aetiology of hypospadias

This article reviews the current evidence and knowledge of the aetiology of hypospadias. Hypospadias remains a fascinating anomaly of the male phallus. It may be an isolated occurrence or part of a syndrome or field defect. The increasing use of assisted reproductive techniques and hormonal manipulation during pregnancy may have been associated with an apparent rise in the incidence of hypospadias. Genetic studies and gene analysis have suggested some defects that could result in hypospadias. New light has also been thrown on environmental factors that could modulate candidate genes, causing altered development of the male external genitalia.

Craniosynostosis and risk factors related to thyroid dysfunction

Thyroid disease is a common problem among women of reproductive age but often goes undiagnosed. Maternal thyroid disease has been associated with increased risk of craniosynostosis. We hypothesized that known risk factors for thyroid disease would be associated with risk of craniosynostosis among women not diagnosed with thyroid disease. Analyses included mothers of 1,067 cases and 8,494 population-based controls who were interviewed for the National Birth Defects Prevention Study. We used multivariable logistic regression to estimate adjusted odds ratios (AOR) and 95% confidence intervals (CI). After excluding women with diagnosed thyroid disease, younger maternal age (AOR 0.7, 95% CI 0.6-0.9, for <25 years versus 25-29), black or other race-ethnicity (AOR 0.3, 95% CI 0.2-0.4 and AOR 0.6, 95% CI 0.4-0.8, respectively, relative to non-Hispanic whites), fertility medications or procedures (AOR 1.5, 95% CI 1.2-2.0), and alcohol consumption (AOR 0.8, 95% CI 0.7-0.9) were associated with risk of craniosynostosis, based on confidence intervals that excluded 1.0. These associations with craniosynostosis are consistent with the direction of their association with thyroid dysfunction (i.e., younger age, black race-ethnicity and alcohol consumption are associated with reduced risk and fertility problems are associated with increased risk of thyroid disease). This study thus provides support for the hypothesis that risk factors associated with thyroid dysfunction are also associated with risk of craniosynostosis. Improved understanding of the potential association between maternal thyroid function and craniosynostosis among offspring is important given that craniosynostosis carries significant morbidity and that thyroid disease is under-diagnosed and potentially modifiable.

Geographic analysis of individual and environmental risk factors for hypospadias births

BACKGROUND

Hypospadias is a relatively common birth defect affecting the male urinary tract. We explored the etiology of hypospadias by examining its spatial distribution in North Carolina and the spatial clustering of residuals from individual and environmental risk factors.

METHODS

We used data collected by the North Carolina Birth Defects Monitoring Program from 2003 to 2005 to estimate local Moran's I statistics to identify geographic clustering of overall and severe hypospadias, using 995 overall cases and 16,013 controls. We conducted logistic regression and local Moran's I statistics on standardized residuals to consider the contribution of individual variables (maternal age, maternal race/ethnicity, maternal education, smoking, parity, and diabetes) and environmental variables (block group land cover) to this clustering.

RESULTS

Local Moran's I statistics indicated significant clustering of overall and severe hypospadias in eastern central North Carolina. Spatial clustering of hypospadias persisted when controlling for individual factors, but diminished somewhat when controlling for environmental factors. In adjusted models, maternal residence in a block group with more than 5% crop cover was associated with overall hypospadias (odds ratio = 1.22; 95% confidence interval = 1.04-1.43); that is living in a block group with greater than 5% crop cover was associated with a 22% increase in the odds of having a baby with hypospadias. Land cover was not associated with severe hypospadias.

CONCLUSION

This study illustrates the potential contribution of mapping in generating hypotheses about disease etiology. Results suggest that environmental factors including proximity to agriculture may play some role in the spatial distribution of hypospadias. Birth Defects Research (Part A) 100:887-894, 2014. © 2014 Wiley Periodicals, Inc.

Maternal parity and the risk of congenital heart defects in offspring: a dose-response meta-analysis of epidemiological observational studies

Background

Epidemiological studies have reported conflicting results regarding maternal parity and the risk of congenital heart defects (CHDs). However, a meta-analysis of the association between maternal parity and CHDs in offspring has not been conducted.

Methods

We searched MEDLINE and EMBASE for articles catalogued between their inception and March 8, 2014; we identified relevant published studies that assessed the association between maternal parity and CHD risk. Two authors independently assessed the eligibility of the retrieved articles and extracted data from them. Study-specific relative risk estimates were pooled by random-effects or fixed-effects models. From the 11272 references, a total of 16 case-control studies and 3 cohort studies were enrolled in this meta-analysis.

Results

The overall relative risk of CHD in parous versus nulliparous women was 1.01 (95% CI, 0.97–1.06; Q = 32.34; P = 0.006; I² = 53.6%). Furthermore, we observed a significant association between the highest versus lowest parity number, with an overall RR = 1.20 (95% CI, 1.10–1.31; (Q = 74.61, P<0.001, I² = 82.6%). A dose–response analysis also indicated a positive effect of maternal parity on CHD risk, and the overall increase in relative risk per one live birth was 1.06 (95% CI, 1.02–1.09); Q = 68.09; P<0.001; I² = 80.9%). We conducted stratified and meta-regression analyses to identify the origin of the heterogeneity among studies. A Galbraith plot was created to graphically assess the sources of heterogeneity.

Conclusion

In summary, this meta-analysis provided a robust estimate of the positive association between maternal parity and risk of CHD.

Differences in risk factors for second and third degree hypospadias in the national birth defects prevention study

BACKGROUND

Hypospadias is a frequent birth defect with three phenotypic subtypes. With data from the National Birth Defects Prevention Study, a large, multi-state, population-based, case-control study, we compared risk factors for second and third degree hypospadias.

METHODS

A wide variety of data on maternal and pregnancy-related risk factors for isolated second and third degree hypospadias was collected by means of computer-assisted telephone interviews to identify potential etiological differences between the two phenotypes. Logistic regression was used to calculate odds ratios including a random effect by study center.

RESULTS

In total, 1547 second degree cases, 389 third degree cases, and 5183 male controls were included in our study. Third degree cases were more likely to have a non-Hispanic black or Asian/Pacific Islander mother, be delivered preterm, have a low birth weight, be small for gestational age, and be conceived with fertility treatments than second degree cases and controls. Associations with both second and third degree hypospadias were observed for maternal age, family history, parity, plurality, and hypertension during pregnancy. Risk estimates were generally higher for third degree hypospadias except for family history.

CONCLUSION

Most risk factors were associated with both or neither phenotype. Therefore, it is likely that the underlying mechanism is at least partly similar for both phenotypes. However, some associations were different between second and third degree hypospadias, and went in opposite directions for second and third degree hypospadias for Asian/Pacific Islander mothers. Effect estimates for subtypes of hypospadias may be over- or underestimated in studies without stratification by phenotype.

Prevalence and factors associated with congenital malformations in tirana, Albania, during 2011-2013

Aim:

Congenital Malformations (CMs) represent a challenge especially for developing countries. Data about CMs in Albania are rather scarce. In this context, our aim was to assess the prevalence and factors associated with CMs in Tirana, the capital of Albania.

Methods:

Information on all CMs at birth during 2011-2013 was retrieved from the National CM Surveillance System. For each CM case, three controls (babies born without CM) were retrieved as well. Overall, 831 cases and 2522 controls were included in this study. The prevalence was calculated using the total number of live births in Tirana during the same period. Binary logistic regression was used to determine the factors associated with CMs adjusting for a number of covariates.

Results:

The three-year prevalence of CMs was 23.41 per 1,000 live births. The most affected body systems were the musculoskeletal, cardiovascular and genital systems. CMs were more prevalent among male babies. Advanced mothers’ age, lower education, unemployment status and lower gestational age were all positively associated with increased likelihood of CMs.

Conclusions:

Socio-demographic factors of mothers are linked to CMs in Albania. Future surveys are needed in Albania in order to establish determinants of CMs at a national level.

Review of genetic and environmental factors leading to hypospadias

Hypospadias is one of the most common congenital malformations, affecting about 4-6 males per 1000 male births, and ranging in severity from a urethral meatus that is slightly off-center to a meatus in the perineal area. Over the past three decades its prevalence may have increased due to changes in reporting of mild cases and/or increased survival of low birth weight infants due to improved neonatal care. However, despite the increasing numbers of males with hypospadias, the overall etiology remains unclear and likely multifactorial in nature. The purpose of this review article is to provide a comprehensive overview of the various factors implicated in hypospadias etiology, including genetic and environmental factors. In addition, we list syndromes in which hypospadias is a relatively common association and delineate the areas that require further investigation in an effort to understand this condition.

A population-based case-control study of drinking-water nitrate and congenital anomalies using Geographic Information Systems (GIS) to develop individual-level exposure estimates

Animal studies and epidemiological evidence suggest an association between prenatal exposure to drinking water with elevated nitrate (NO₃-N) concentrations and incidence of congenital anomalies. This study used Geographic Information Systems (GIS) to derive individual-level prenatal drinking-water nitrate exposure estimates from measured nitrate concentrations from 140 temporally monitored private wells and 6 municipal water supplies. Cases of major congenital anomalies in Kings County, Nova Scotia, Canada, between 1988 and 2006 were selected from province-wide population-based perinatal surveillance databases and matched to controls from the same databases. Unconditional multivariable logistic regression was performed to test for an association between drinking-water nitrate exposure and congenital anomalies after adjusting for clinically relevant risk factors. Employing all nitrate data there was a trend toward increased risk of congenital anomalies for increased nitrate exposure levels though this was not statistically significant. After stratification of the data by conception before or after folic acid supplementation, an increased risk of congenital anomalies for nitrate exposure of 1.5–5.56 mg/L (2.44; 1.05–5.66) and a trend toward increased risk for >5.56 mg/L (2.25; 0.92–5.52) was found. Though the study is likely underpowered, these results suggest that drinking-water nitrate exposure may contribute to increased risk of congenital anomalies at levels below the current Canadian maximum allowable concentration.

Epidemiologic features of male genital malformations and subtypes in Texas

Although distinct categories of male genital malformations share some common risk factors, few studies have systematically compared epidemiologic features across phenotypes. We evaluated the relationship between several maternal and infant characteristics and five categories of male genital malformations: second- or third-degree hypospadias, hypospadias (regardless of degree), small penis, cryptorchidism, and any male genital malformation. Data for 16,813 cases with isolated male genital malformations and 1,945,841 male live births delivered from 1999 to 2008 were obtained from the Texas Birth Defects Registry. For each phenotype category, 13 maternal and infant variables were assessed, and adjusted prevalence ratios were estimated based on the same multivariable Poisson regression model. A significant negative association was observed between previous live births versus no previous live births and four phenotypes (e.g., adjusted prevalence ratio [aPR] for any male genital malformation: 0.78, 95% confidence interval [CI]: 0.75-0.81). The prevalence of 4 of the phenotypes was significantly higher among multiple versus singleton pregnancies (e.g., aPR for any male genital malformation: 1.35, 95% CI: 1.25-1.47). We also observed significant associations between multiple phenotypes and residential region at delivery, delivery year, month of conception, and maternal age, race/ethnicity, education, and birthplace, including significant associations for trends (maternal age, maternal education, and birth year modeled ordinally). Our results allow for comparison of characteristics across phenotypes and suggest that there may be some common risk factors for multiple male genital malformations (e.g., characteristics related to maternal estrogen levels), while other risk factors may be unique to specific defects.

Maternal age, parity and isolated birth defects: a population-based case-control study in Shenzhen, China

Background

The etiology of birth defects has been widely studied but is not yet fully clarified, previously published data had suggested that maternal age or parity maybe involved, but without consistent conclusions.

Methods

A population-based, case-control study was nested in a cohort of perinatal infants born from 2010 to 2012 in Baoan District, Shenzhen. Four categories of isolated birth defects were defined as cases: congenital heart defects (CHD, n = 693), polydactyly (n = 352), cleft lip with or without palate (CL/P, n = 159) and equinovarus (n = 119). Controls were non-malformed infants (n = 11,307) randomly selected from the same area and period. Odds ratios (ORs) and the 95% confidence intervals (CIs) were computed by multivariable unconditional logistic regression analysis.

Results

Young maternal age (<25 years old) was associated with a reduced risk of CHD (adjusted OR = 0.73, 95% CI 0.59–0.90), while with an elevated risk of polydactyly (adjusted OR = 1.42, 95% CI 1.09-1.84). Increased risk of CL/P-affected pregnancy was observed in mothers older than 35 years old (adjusted OR = 2.12, 95% CI 1.26–3.57). Compared to primipara, those having their second, and third or more delivery were less likely to have infants with equinovarus, with significant adjusted ORs of 0.59 (0.40–0.89) and 0.42 (0.19–0.93), respectively.

Conclusion

Maternal age was significantly associated with CHD, polydactyly and CL/P relevant pregnancy. Mothers with higher parity might have lower risk of equinovarus occurrence in offsprings.

Maternal medication and herbal use and risk for hypospadias: data from the National Birth Defects Prevention Study, 1997-2007

PURPOSE

To investigate associations between maternal use of common medications and herbals during early pregnancy and risk for hypospadias in male infants.

METHODS

We used data from the National Birth Defects Prevention Study, a multi-site, population-based, case-control study. We analyzed data from 1537 infants with second-degree or third-degree isolated hypospadias and 4314 live-born male control infants without major birth defects, with estimated dates of delivery from 1997 to 2007. Exposure was reported use of prescription or over-the-counter medications or herbal products, from 1 month before to 4 months after conception. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, adjusting for maternal age, race/ethnicity, education, pre-pregnancy body mass index, previous live births, maternal subfertility, study site, and year.

RESULTS

We assessed 64 medication and 24 herbal components. Maternal uses of most components were not associated with an increased risk of hypospadias. A new associations was observed for venlafaxine (aOR 2.4; 95%CI 1.0, 6.0) [Correction made here after initial online publication.]. The previously reported association for clomiphene citrate was confirmed (aOR 1.9; 95%CI 1.2, 3.0). Numbers were relatively small for exposure to other specific patterns of fertility agents, but elevated aORs were observed for the most common of them.

CONCLUSIONS

Overall, findings were reassuring that hypospadias is not associated with most medication components examined in this analysis. New associations will need to be confirmed in other studies. Increased risks for hypospadias associated with various fertility agents raise the possibility of confounding by underlying subfertility.

Association between maternal age and birth defects of unknown etiology: United States, 1997-2007

BACKGROUND

Birth defects affect 3% of babies born, and are one of the leading causes of infant mortality. Both younger and older maternal age may pose increased risks for certain birth defects. This study assessed the relationship between maternal age at the estimated delivery date and the risk for birth defects.

METHODS

Data were obtained from the National Birth Defects Prevention Study, a population-based case-control study including mothers across 10 states. Maternal age was stratified into six categories: <20, 20 to 24, 25 to 29, 30 to 34, 35 to 39, and ≥40 years, and also analyzed as a continuous variable. Logistic regression models adjusted formaternal race/ethnicity, education, body mass index (BMI), folic acid use, smoking, gravidity, and parental age difference were used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

For maternal age <20 years, associations with total anomalous pulmonary venous return (aOR, 2.3; 95% CI, 1.3-4.0), amniotic band sequence (aOR, 2.4; 95% CI, 1.5-3.8), and gastroschisis (aOR, 6.1; 95% CI, 4.8-8.0) were observed. For the ≥40 year age group, associations with several cardiac defects, esophageal atresia (aOR, 2.9; 95% CI, 1.7-4.9), hypospadias (aOR, 2.0; 95% CI, 1.4-3.0), and craniosynostosis (aOR, 1.6; 95% CI, 1.1-2.4) were observed. Results using maternal age as a continuous variable were consistent with those that used categorized maternal age.

CONCLUSION

Elucidating risk factors specific to women ateither extreme of maternal age may offer prevention opportunities. All women should be made aware of prevention opportunities, such as folic acid supplementation, to reduce the occurrence of birth defects.

Racial/ethnic variations in the prevalence of selected major birth defects, metropolitan Atlanta, 1994-2005

OBJECTIVES

Birth defects are the leading cause of infant mortality and are responsible for substantial child and adult morbidity. Documenting the variation in prevalence of birth defects among racial/ethnic subpopulations is critical for assessing possible variations in diagnosis, case ascertainment, or risk factors among such groups.

METHODS

We used data from the Metropolitan Atlanta Congenital Defects Program, a population-based birth defects registry with active case ascertainment. We estimated the racial/ethnic variation in prevalence of 46 selected major birth defects among live births, stillbirths, and pregnancy terminations at >20 weeks gestation among mothers residing in the five central counties of metropolitan Atlanta between 1994 and 2005, adjusting for infant sex, maternal age, gravidity, and socioeconomic status (SES). We also explored SES as a potential effect measure modifier.

RESULTS

Compared with births to non-Hispanic white women, births to non-Hispanic black women had a significantly higher prevalence of five birth defects and a significantly lower prevalence of 10 birth defects, while births to Hispanic women had a significantly higher prevalence of four birth defects and a significantly lower prevalence of six birth defects. The racial/ethnic disparities in the prevalence of some defects varied by SES, but no clear pattern emerged.

CONCLUSIONS

Racial/ethnic disparities were suggested in 57% of included birth defects. Disparities in the prevalence of birth defects may result from different underlying genetic susceptibilities; exposure to risk factors; or variability in case diagnosis, ascertainment, or reporting among the subpopulations examined. Policies that improve early diagnosis of birth defects could reduce associated morbidity and mortality.

Is maternal parity an independent risk factor for birth defects?

BACKGROUND

Although associations between maternal parity and birth defects have been observed previously, few studies have focused on the possibility that parity is an independent risk factor for birth defects. We investigated the relation between levels of parity and a range of birth defects, adjusting each defect group for the same covariates.

METHODS

We included infants who had an estimated delivery date between 1997 and 2007 and participated in the National Birth Defects Prevention Study, a multisite case-control study. Cases included infants or fetuses belonging to 38 phenotypes of birth defects (n = 17,908), and controls included infants who were unaffected by a major birth defect (n = 7173). Odds ratios (ORs) were adjusted for 12 covariates using logistic regression.

RESULTS

Compared with primiparous mothers, nulliparous mothers were more likely to have infants with amniotic band sequence, hydrocephaly, esophageal atresia, hypospadias, limb reduction deficiencies, diaphragmatic hernia, omphalocele, gastroschisis, tetralogy of Fallot, and septal cardiac defects, with significant ORs (1.2 to 2.3). Compared with primiparous mothers, multiparous mothers had a significantly increased risk of omphalocele, with an OR of 1.5, but had significantly decreased risk of hypospadias and limb reduction deficiencies, with ORs of 0.77 and 0.77.

CONCLUSIONS

Nulliparity was associated with an increased risk of specific phenotypes of birth defects. Most of the phenotypes associated with nulliparity in this study were consistent with those identified by previous studies. Research into biologic or environmental factors that are associated with nulliparity may be helpful in explaining some or all of these associations.

Aetiology of hypospadias: a systematic review of genes and environment

BACKGROUND

Hypospadias is a common congenital malformation of the male external genitalia. Most cases have an unknown aetiology, which is probably a mix of monogenic and multifactorial forms, implicating both genes and environmental factors. This review summarizes current knowledge about the aetiology of hypospadias.

METHODS

Pubmed was used to identify studies on hypospadias aetiology published between January 1995 and February 2011. Reference lists of the selected manuscripts were also searched to identify additional studies, including those published before 1995.

RESULTS

The search provided 922 articles and 169 articles were selected for this review. Studies screening groups of patients with hypospadias for single gene defects found mutations in WT1, SF1, BMP4, BMP7, HOXA4, HOXB6, FGF8, FGFR2, AR, HSD3B2, SRD5A2, ATF3, MAMLD1, MID1 and BNC2. However, most investigators are convinced that single mutations do not cause the majority of isolated hypospadias cases. Indeed, associations were found with polymorphisms in FGF8, FGFR2, AR, HSD17B3, SRD5A2, ESR1, ESR2, ATF3, MAMLD1, DGKK, MID1, CYP1A1, GSTM1 and GSTT1. In addition, gene expression studies indentified CTGF, CYR61 and EGF as candidate genes. Environmental factors consistently implicated in hypospadias are low birthweight, maternal hypertension and pre-eclampsia, suggesting that placental insufficiency may play an important role in hypospadias aetiology. Exogenous endocrine-disrupting chemicals have the potential to induce hypospadias but it is unclear whether human exposure is high enough to exert this effect. Other environmental factors have also been associated with hypospadias but, for most, the results are inconsistent.

CONCLUSIONS

Although a number of contributors to the aetiology of hypospadias have been identified, the majority of risk factors remain unknown.

Time trends and geographic variations in the prevalence of hypospadias in China

BACKGROUND

Little is known about the main epidemiologic characteristics of hypospadias prevalence in China. We investigated the time trends and geographic variations in the prevalence of hypospadias in China from 1996 to 2008.

METHODS

Data were retrieved from the hospital-based birth defects monitoring system in China from 1996 to 2008. We used prevalence ratios (PRs) to describe the difference in prevalence of hypospadias between urban and rural areas, as well as among different regions. Poisson regression was used to explore the long time trend for the prevalence of hypospadias and its regional disparity.

RESULTS

The prevalences of hypospadias for isolated anomalies, multiple anomalies, and overall cases were 7.64, 1.39, and 9.03 per 10,000 births, respectively. The national PRs (urban vs. rural) of hypospadias for overall and isolated cases were 1.25 (95% confidence interval [CI], 1.16-1.35) and 1.27 (95% CI, 1.17-1.38), respectively. The highest prevalence (12.10 per 10,000 births) was observed in the eastern region. A positive correlation was found between the prevalence of hypospadias and maternal age (p < 0.01). The average annual increase of 7.43% (95% CI, 5.52-9.38%) was observed in the overall prevalence of hypospadias in China; it was 5.28% (95% CI, 4.16-6.43%) in urban areas, 9.79% (95% CI, 7.72-11.90%) in rural areas, 9.08% (95% CI, 6.36-11.86%) in the eastern region, 4.76% (95% CI, 2.93-6.62%) in the central region, and 6.57% (95% CI, 4.44-8.74%) in the western region.

CONCLUSION

The increasing trends and differences of hypospadias prevalence by urban-rural classification and geographical location suggest that environmental exposure and maternal age might have a critical role in the development of hypospadias.

No association between maternal pre-pregnancy obesity and risk of hypospadias or cryptorchidism in male newborns

BACKGROUND

Hypospadias and cryptorchidism, two relatively common male genital anomalies, may be caused by altered maternal hormone levels, blood glucose levels, or nutritional deficiencies. Maternal obesity, which increases risk of diabetes and could influence hormone levels, may, therefore, be associated with risk of hypospadias and cryptorchidism. The purpose of this study was to assess the association between pre-pregnancy maternal obesity and hypospadias and cryptorchidism.

METHODS

We conducted a case-control study of hypospadias and cryptorchidism in male singleton newborns using Washington State birth records from 1992 to 2008 linked to birth-hospitalization discharge records. Maternal pre-pregnancy body mass index (BMI) was calculated from pre-pregnancy weight and height. Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) for hypospadias or cryptorchidism were estimated by fitting multivariable logistic regression models adjusted for year of birth, and maternal age, education, parity, race, and cigarette smoking during pregnancy.

RESULTS

The complete-case analysis included 2219 hypospadias cases, 2563 cryptorchidism cases, and 32,734 controls. Maternal obesity (BMI ≥30 kg/m(2) ) was not associated with risk of hypospadias or cryptorchidism in male offspring: hypospadias (aOR, 1.07; 95% CI, 0.95-1.21); cryptorchidism (aOR, 0.99; 95% CI, 0.89-1.11), and no trend in risk with increasing maternal BMI was found. There was little indication of risk associated with BMI among any subgroup of mothers examined, including women with pre-existing diabetes or hypertension, women who developed preeclampsia, non-Hispanic white women, first-time mothers, or mothers aged ≥30 years.

CONCLUSIONS

The results of this study do not support the hypothesis that pre-pregnancy maternal obesity is a cause of hypospadias or cryptorchidism in male infants.

Maternal exposures to endocrine disrupting chemicals and hypospadias in offspring

BACKGROUND

Prenatal exposures to endocrine-disrupting chemicals (EDCs) are suspected risk factors in the etiology of hypospadias. The aim of this case-control study was to test the hypothesis of an association between maternal environmental exposures to EDCs and hypospadias in the offspring.

METHODS

Detailed questionnaire data on occupational and dietary exposures to EDCs in the perinatal period were collected from 80 mothers with hypospadiac infants and from 80 mothers with healthy controls within 24 months of childbirth. Maternal exposure to selected EDCs was also ascertained by measuring the concentration of dichlorodiphenyldichloroethylene, hexachlorobenzene, and several polychlorinated biphenyl congeners in the serum of primiparous mothers of 37 cases and 21 controls.

RESULTS

The risk to bear an hypospadiac infant was associated with perinatal maternal occupational exposures to EDCs evaluated by a job-exposure matrix: jobs with exposure to one class of EDCs (odds ratios [OR](crude), 2.83; 95% confidence intervals [CI], 1.32-6.07; OR(adjusted), 2.44; 95% CI, 1.06-5.61) and jobs with exposure to more than one group of EDCs (OR(crude), 4.27; 95% CI, 1.43-12.78; OR(adjusted), 4.11; 95%CI, 1.34-12.59). Increase in risk was also found among mothers consuming a diet rich in fish or shellfish (OR(crude), 3.41; 95% CI, 1.42-8.23; OR(adjusted), 2.73; 95%CI, 1.09-6.82). Serum hexachlorobenzene concentration above the median of all subjects was significantly associated with the risk of hypospadias (OR(adjusted), 5.50; 95% CI, 1.24-24.31).

CONCLUSIONS

This study, although based on a limited number of cases, for the first time provides evidence of an association between maternal exposure to EDCs, in particular elevated plasma hexachlorobenzene concentration, and the development of hypospadias in the offspring.

Hypospadias and halogenated organic pollutant levels in maternal mid-pregnancy serum samples

BACKGROUND

Environmental contaminants that disrupt endocrine function may contribute to hypospadias etiology.

OBJECTIVE

To compare levels of selected halogenated organic pollutants in women delivering infants with and without hypospadias.

METHODS

This study examined levels of nine polybrominated flame retardants (PBDEs), 30 polychlorinated biphenyls (PCBs) and nine persistent pesticides in mid-pregnancy serum samples from 20 women who delivered infants with hypospadias and 28 women who delivered unaffected infants, in California. Analytes were measured using isotope dilution high-resolution mass spectrometry. Values below individual limits of detection (LOD) for each analyte were imputed based on a truncated multivariate normal distribution. Levels of 17 analytes for which at least 50% of cases and controls had values above the LOD were compared using t-tests and by generating odds ratios from logistic regression analyses.

RESULTS

Means were greater for cases than controls for 11 of the 17 reported analytes (4 of 5 PBDEs, 7 of 9 PCBs, and 0 of 3 other persistent pesticides), but none of the differences were statistically significant. Eleven of the 17 odds ratios exceeded one (the same analytes that had greater means), but none of the confidence intervals excluded one. After adjustment for sample processing time and foreign-born Hispanic race-ethnicity, only four of the odds ratios exceeded one.

CONCLUSIONS

Levels of the PBDEs and PCBs were not statistically significantly different, but the sample size was small. The current study adds to a relatively limited knowledge base regarding the potential association of specific contaminants with hypospadias or other birth defects.