Female alcohol consumption and fecundability: a systematic review and dose-response meta-analysis

Investigating fertility health knowledge and lifestyle risk factors among Nigerian university students: A cross-sectional survey

OBJECTIVES

Adolescents who are unaware of infertility risk factors and the long-term health effects of their lifestyle choices may participate in unsafe sexual and lifestyle behaviors. Their reproductive goals and health may be affected by such behaviors. Adolescents' awareness of male and female infertility risk factors was assessed, along with lifestyle risk variables related to sexual behavior and psychoactive substance use. The causes of inconsistent condom use were also examined.

METHODS

In 2022, a cross-sectional survey was undertaken involving 598 sexually active university students from Nigeria (18.6 years±0.9), the majority of whom were female (57.2 %). Descriptive statistics, bivariate analysis, and binary logistic regression were utilized in the data analysis to determine the influence of lifestyle factors and levels of knowledge on fertility.

RESULTS

Most participants had a moderate understanding of male and female infertility risk factors. The results showed that female students were more informed. Multiple sexual partners and psychoactive substance use were common lifestyle variables. Younger female students, those with several partners, and participants who frequently used alcohol and narcotics used condoms inconsistently.

CONCLUSIONS

The study emphasizes the need for fertility health and lifestyle risk education for Nigerian youth. Despite moderate knowledge, lifestyle implications on fertility are unclear. Fertility health education in schools could help students make informed reproductive choices and lower the risk of infertility and chronic diseases. Research is needed to confirm findings and inform nationwide targeted interventions.

Examining the Role of Nutrition in Cancer Survivorship and Female Fertility: A Narrative Review

Female cancer survivors have a higher chance of experiencing infertility than females without a history of cancer diagnosis. This risk remains high despite advances in fertility treatments. There is a need to augment fertility treatments with cost-effective methods such as nutritional guidance to improve fertility chances. The aim of this review article is to connect the current literature on cancer survivorship nutrition and fertility nutrition, focusing on the importance of integrating nutritional guidance into fertility counseling, assessment, and treatment for female cancer survivors. Consuming a healthful diet comprising whole grains, soy, fruits, vegetables, seafood, and unsaturated fats has improved both female fertility and cancer survivorship. Similarly, maintaining a healthy body weight also improves female fertility and cancer survivorship. Therefore, dietary interventions to support female cancer survivors with fertility challenges are of immense importance. The period of follow-up fertility counseling and assessment after cancer treatment may provide a unique opportunity for implementing nutritional guidance for female cancer survivors. Dietary interventions are a promising strategy to improve pregnancy chances and overall quality of life among female cancer survivors; thus, researchers should investigate perceptions regarding fertility, barriers, and challenges to changing nutrition-related behaviors, and preferences for nutritional guidance to support fertility treatments in this population.

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.

EASL Clinical Practice Guidelines on the management of liver diseases in pregnancy

Liver diseases in pregnancy comprise both gestational liver disorders and acute and chronic hepatic disorders occurring coincidentally in pregnancy. Whether related to pregnancy or pre-existing, liver diseases in pregnancy are associated with a significant risk of maternal and fetal morbidity and mortality. Thus, the European Association for the Study of Liver Disease invited a panel of experts to develop clinical practice guidelines aimed at providing recommendations, based on the best available evidence, for the management of liver disease in pregnancy for hepatologists, gastroenterologists, obstetric physicians, general physicians, obstetricians, specialists in training and other healthcare professionals who provide care for this patient population.

Assessment of Prior Infection With Hepatitis B Virus and Fecundability in Couples Planning Pregnancy

IMPORTANCE

The association of hepatitis B virus (HBV) infection with reduced fecundability among reproductive-aged couples lacks large-population, in-depth study evidence.

OBJECTIVE

To investigate the association of HBV infection with time to pregnancy in couples planning pregnancy, and to explore whether this association varied by gravidity, health statuses, or lifestyles.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based cohort study of Chinese couples participating in the National Free Preconception Check-up Projects during 2015 to 2017. They were planning pregnancy and were followed-up every 3 months until getting pregnant, as confirmed by gynecologic ultrasonography, or were followed-up for 1 year. Data were analyzed between March 1, 2022, and September 30, 2022.

MAIN OUTCOMES AND MEASURES

The main outcome was time to pregnancy, assessed using fecundability hazard ratios (HRs). The Cox proportional hazards regression models were used to estimate the association of HBV infection with fecundability.

RESULTS

Among 2 419 848 couples (mean [SD] age, 27.87 [5.20] years for women and 29.58 [5.50] years for men), 126 728 women (5.24%) and 156 572 men (6.47%) were infected with HBV. Compared with the HBV-negative group, the fecundability of both women and men in the HBV-positive group decreased by 5% (HR, 0.95; 95% CI, 0.94-0.95). Compared with couples in which both partners were HBV negative, the fecundability of those in which both partners were HBV positive declined by 6% (HR, 0.94; 95% CI, 0.93-0.96) among all couples, by 3% (HR, 0.97; 95% CI, 0.95-0.99) among nulligravidas couples, and by 7% (HR, 0.93; 95% CI, 0.91-0.95) among multigravidas couples. Both the female-male and couple models suggested that the association of HBV infection with decreased fecundability was more pronounced in couples with multigravidas. The negative association was greater in people with overweight and obesity and was inconsistent in certain subgroups; in particular, it was more pronounced in women with reproductive tract infections, normal fasting plasma glucose, and no alcohol intake and in men with normal blood pressure.

CONCLUSIONS AND RELEVANCE

In this population-based cohort study, HBV infection was associated with decreased fecundability in a general reproductive-aged population, especially in couples with multigravidas. For women and men with certain health statuses and lifestyles, a comprehensive consideration of this association is recommended to provide personalized fertility guidance.

Associations between health behaviours, fertility and reproductive outcomes: triangulation of evidence in the Norwegian Mother, Father and Child Cohort Study (MoBa)

BACKGROUND

Guidance to improve fertility includes reducing alcohol and caffeine consumption, achieving healthy weight-range and stopping smoking. Advice is informed by observational evidence, which is often biased by confounding.

METHODS

This study primarily used data from a pregnancy cohort, the Norwegian Mother, Father and Child Cohort Study. First, we conducted multivariable regression of health behaviours (alcohol and caffeine consumption, body-mass index (BMI), and smoking) on fertility outcomes (e.g. time to conception) and reproductive outcomes (e.g. age at first birth) (n = 84,075 females, 68,002 males), adjusting for birth year, education and attention-deficit and hyperactive-impulsive (ADHD) traits. Second, we used individual-level Mendelian randomisation (MR) to explore possible causal effects of health behaviours on fertility/reproductive outcomes (n = 63,376 females, 45,460 males). Finally, we performed summary-level MR for available outcomes in UK Biobank (n = 91,462-1,232,091) and controlled for education and ADHD liability using multivariable MR.

RESULTS

In multivariable regression analyses, higher BMI associated with fertility (longer time to conception, increased odds of infertility treatment and miscarriage), and smoking was associated with longer time to conception. In individual-level MR analyses, there was strong evidence for effects of smoking initiation and higher BMI on younger age at first birth, of higher BMI on increased time to conception, and weak evidence for effects of smoking initiation on increased time to conception. Age at first birth associations were replicated in summary-level MR analysis; however, effects attenuated using multivariable MR.

CONCLUSIONS

Smoking behaviour and BMI showed the most consistent associations for increased time to conception and a younger age at first birth. Given that age at first birth and time to conception are positively correlated, this suggests that the mechanisms for reproductive outcomes are distinct to the mechanisms acting on fertility outcomes. Multivariable MR suggested that effects on age at first birth might be explained by underlying liability to ADHD and education.

Development of a nutrition screening tool to identify need for dietetic intervention in female infertility

BACKGROUND

One in seven couples are impacted by infertility in the UK, and female infertility is often associated with several health conditions impacted by nutrition. Despite many studies aimed at identifying the critical role of nutrition in infertility, there is currently no screening tool that identifies nutritional risk factors for infertility.

AIM

To propose a self-administered screening tool to identify women who would benefit from nutritional intervention to promote fertility.

METHODS

A narrative review was carried out to identify and summarise modifiable nutritional risk factors that can influence female fertility, including comorbidities that can influence nutrition intake, absorption, and metabolism.

KEY FINDINGS

A nutrition screening tool outlining modifiable nutrition risk factors potentially improving female fertility has been proposed, comprising of BMI, medical history and quality of diet and lifestyle which would aid in designing evidence based dietetic services for female infertility.

Modifiable Risk Factor Score and Fecundability in a Preconception Cohort in Singapore

IMPORTANCE

Although multiple modifiable risk factors have been identified for reduced fecundability (defined as lower probability of conception within a menstrual cycle), no scoring system has been established to systematically evaluate fecundability among females who are attempting to conceive.

OBJECTIVE

To examine the association of a risk score based on 6 modifiable factors with fecundability, and to estimate the percentage reduction in incidence of nonconception if all study participants achieved a minimal risk score level.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study obtained data from the S-PRESTO (Singapore Preconception Study of Long-Term Maternal and Child Outcomes) prospective cohort study. Females of reproductive age who were trying to conceive were enrolled from February 2015 to October 2017 and followed for 1 year, ending in November 2018. Data were analyzed from March to May 2022.

EXPOSURES

A reduced fecundability risk score was derived by giving participants 1 point for each of the following factors: unhealthy body mass index, unhealthy diet, smoking, alcohol intake, folic acid supplement nonuser, and older maternal age. Total scores ranged from 0 to 6 and were classified into 5 levels: level 1 (score of 0 or 1), level 2 (score of 2), level 3 (score of 3), level 4 (score of 4), and level 5 (score of 5 or 6).

MAIN OUTCOMES AND MEASURES

Fecundability, measured by time to conception in cycles, was analyzed using discrete-time proportional hazards models with confounder adjustment.

RESULTS

A total of 937 females (mean [SD] age, 30.8 [3.8] years) were included, among whom 401 (42.8%) spontaneously conceived within 1 year of attempting conception; the median (IQR) number of cycles before conception was 4 (2-7). Compared with participants with a level 1 risk score, those with level 2, 3, 4, and 5 risk scores had reductions in fecundability of 31% (adjusted fecundability ratio [FR], 0.69; 95% CI, 0.54-0.88), 41% (FR, 0.59; 95% CI, 0.45-0.78), 54% (FR, 0.46; 95% CI, 0.31-0.69) and 77% (FR, 0.23; 95% CI, 0.07-0.73), respectively. Assessment of the population attributable fraction showed that all participants achieving a minimal (level 1) risk level would be associated with a reduction of 34% (95% CI, 30%-39%) in nonconception within a year.

CONCLUSIONS AND RELEVANCE

Results of this study revealed the co-occurrence of multiple modifiable risk factors for lowered fecundability and a substantially higher conception rate among participants with no or minimal risk factors. The risk assessment scoring system proposed is a simple and potentially useful public health tool for mitigating risks and guiding those who are trying to conceive.

Dietary Supplement Intake and Fecundability in a Singapore Preconception Cohort Study

Subfertility is a global problem affecting millions worldwide, with declining total fertility rates. Preconception dietary supplementation may improve fecundability, but the magnitude of impact remains unclear. This prospective cohort study aimed to examine the association of preconception micronutrient supplements with fecundability, measured by time to pregnancy (TTP). The study was conducted at KK Women's and Children's Hospital, Singapore, between February 2015 and October 2017, on 908 women aged 18-45 years old, who were trying to conceive and were enrolled in the Singapore PREconception Study of long-Term maternal and child Outcomes (S-PRESTO). Baseline sociodemographic characteristics and supplement intake were collected through face-to-face interviews. The fecundability ratio (FR) was estimated using discrete-time proportional hazard modelling. Adjusting for potentially confounding variables, folic acid (FA) (FR 1.26, 95% confidence interval 1.03-1.56) and iodine (1.28, 1.00-1.65) supplement users had higher fecundability compared to non-users. Conversely, evening primrose oil supplement users had lower fecundability (0.56, 0.31-0.99) than non-users. In this study, preconception FA and iodine supplementation were associated with shortened TTP, while evening primrose oil use was associated with longer TTP. Nonetheless, the association between supplement use and the magnitude of fecundability changes will need to be further confirmed with well-designed randomised controlled trials.

Association studies between chromosomal regions 1q21.3, 5q21.3, 14q21.2 and 17q21.31 and numbers of children in Poland

Number of children is an important human trait and studies have indicated associations with single-nucleotide polymorphisms (SNPs). Aim: to give further evidence for four associations using a large sample of Polish subjects. Data from the POPULOUS genetic database was provided from anonymous, healthy, unrelated, Polish volunteers of both sexes (N = 5760). SNPs (n = 173) studied: (a) 69 from the chromosome 17 H1/H2 inversion; (b) six from 1q21.3, 5q21.3 and 14q21.2; and (c) 98 random negative controls. Zero-inflated negative-binomial regression (z.i.) was performed (0-3 numbers of children per individual (NCI) set as non-events; adjustors: year of birth, sex). Significance level p = 0.05 with Bonferroni correction. Statistically-significant differences (with data from both sexes combined) were obtained from highly-linked inversion SNPs: representative rs12373123 gave means: homozygotes TT: 2.31 NCI (n = 1418); heterozygotes CT: 2.35 NCI (n = 554); homozygotes CC: 2.44 NCI (n = 43) (genotype p = 0.01; TTvs.CC p = 0.004; CTvs.CC p = 0.009). (Male data alone gave similar results.) Recessive modeling indicated that H2-homozygotes had 0.118 more children than H1-homozygotes + heterozygotes (z.i.-count estimates ± standard errors: CT, - 0.508 ± 0.194; TT, - 0.557 ± 0.191). The non-over-dispersed count model detected no interactions: of importance there was no significant interaction with age. No positive results were obtained from negative-control SNPs or (b). Conclusions: association between the H1/H2 inversion and numbers of children (previously reported in Iceland) has been confirmed, albeit using a different statistical model. One limitation is the small amount of data, despite initially ~ 6000 subjects. Causal studies require further investigation.

The association between caffeine and alcohol consumption and IVF/ICSI outcomes: A systematic review and dose-response meta-analysis

INTRODUCTION

The objective of this study was to evaluate the association between caffeine and alcohol consumption and in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) outcomes.

MATERIAL AND METHODS

The protocol was registered in the PROSPERO database on May 23, 2021 (registration number: CRD42021256649), and updated on August 4, 2022. Two researchers performed a literature search in the PubMed, Embase, and MEDLINE databases for articles published before July 15, 2022 independently. Studies investigating the association between caffeine and alcohol consumption and IVF/ICSI outcomes were included, and studies reporting the consumption amount were analyzed using a one-stage robust error meta-regression-based method to explore potential dose-response relation. Funnel plot was used to assess publication bias if more than 10 studies were included.

RESULTS

Twelve studies on caffeine consumption and 14 studies on alcohol consumption were included in the systematic review, of which seven and nine were eligible for the meta-analysis. These studies included 26 922 women and/or their spouses who underwent IVF/ICSI treatment. Women's and men's caffeine consumption was not significantly associated with the pregnancy rate (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.85-1.12; OR 0.93, 95% CI 0.75-1.14; respectively) and the live birth rate (OR 0.98, 95% CI 0.89-1.08; OR 0.98, 95% CI 0.86-1.12; respectively) of IVF/ICSI. Maternal alcohol consumption was negatively associated with pregnancy after IVF/ICSI treatment (OR 0.83, 95% CI 0.69-1.01). Paternal alcohol consumption was negatively associated with partner's live birth after IVF/ICSI treatment (OR 0.88, 95% CI 0.79-0.99). Compared with abstainers, the chance of achieving a pregnancy after IVF/ICSI treatment decreased by 7% for women who consumed 84 g alcohol per week (OR 0.93, 95% CI 0.90-0.98), and the chance of partners achieving a live birth decreased by 9% for men who consumed 84 g alcohol per week (OR 0.91, 95% CI 0.88-0.94).

CONCLUSIONS

There was no association between caffeine consumption and pregnancy or live birth rate of IVF/ICSI. Women's alcohol consumption was associated with decreased pregnancy rate after IVF/ICSI treatment when weekly consumption was greater than 84 g. Men's alcohol consumption was associated with decreased live birth rate after IVF/ICSI treatment when weekly consumption was greater than 84 g.

Beverage intake and ovarian reserve among women from a fertility center

OBJECTIVE

To evaluate the associations of caffeinated, alcoholic, and sweetened beverage intakes with antral follicle count (AFC), a well-accepted biomarker of ovarian reserve.

DESIGN

Observational prospective cohort study.

SETTING

Fertility center at an academic hospital.

PATIENTS

This study includes 567 women seeking fertility care at the Massachusetts General Hospital who participated in the Environment and Reproductive Health Study.

INTERVENTION

None. Women self-reported consumption of caffeinated (coffee, tea, soda), alcoholic (wine, beer, liquor), sugar-sweetened, and artificially sweetened beverages using a validated food-frequency questionnaire.

MAIN OUTCOME MEASURE

Antral follicle count was assessed using a transvaginal ultrasound performed on the 3rd day of an unstimulated menstrual cycle or on the 3rd day of a progesterone withdrawal bleed.

RESULTS

Median (interquartile range) age and AFC were 35.0 (32.0-38.0) years and 13.0 (9.0-18.0), respectively. Median (range) intake of caffeinated, alcoholic, sugar-sweetened, and artificially sweetened beverages in servings/day were 1.08 (0-7.08), 0.35 (0-3.84), 0.04 (0-4.80), and 0.04 (0-7.50), respectively. All examined beverages were unrelated to AFC. The multivariable adjusted mean AFC (95% confidence interval) for women in the top and bottom quartiles of intake were 13.8 (13.0-14.7) and 13.8 (12.9-14.7) for caffeinated beverages; 13.8 (13.0-14.7) and 13.8 (13.0-14.6) for alcoholic beverages; 13.5 (12.6-14.4) and 13.3 (12.4-14.2) for sugar-sweetened beverages; and 13.2 (12.4-14.1) and 13.4 (12.6-14.3) for artificially sweetened beverages.

CONCLUSION

Low-to-moderate intakes of caffeinated, alcoholic, sugar-sweetened, and artificially sweetened beverages were unrelated to ovarian reserve, as measured by AFC, in a cohort of women seeking fertility care.

The current situation and future directions for the study on time-to-pregnancy: a scoping review

Introduction

As problems associated with infertility and population aging increase, there is a growing interest in the factors that cause a decline in human fertility. Time-to-pregnancy (TTP) is a good indicator with which to reflect human fecundability. Here, we present a comprehensive overview of this topic.

Methods

Relevant qualitative and quantitative studies were identified by searching the Web of science and PubMed electronic databases. We included all literature, written in English, from inception to the 10th April 2021 providing the focus was on TTP. We conducted a narrative synthesis using thematic analysis.

Results

Traditional TTP-related study protocols include prospective and retrospective cohorts that provide a wealth of data to reveal potential influences on TTP. Thus far, a variety of factors have been shown to be associated with TTP in couples preparing for pregnancy, including basic demographic characteristics, menstrual status, chronic disease status, environmental endocrine disruptor exposure, and lifestyles. However, there are inevitable epidemiological bias in the existing studies, including recall bias, selection bias and measurement bias. Some methodological advances have brought new opportunities to TTP research, which make it possible to develop precision interventions for population fertility. Future TTP studies should take advantage of artificial intelligence, machine learning, and high-throughput sequencing technologies, and apply medical big data to fully consider and avoid possible bias in the design.

Conclusion

There are many opportunities and future challenges for TTP related studies which would provide a scientific basis for the “precise health management” of the population preparing for pregnancy.

As the problems of infertility and population aging increase, there is a growing interest in the factors that cause a decline in human fertility. Time-to-pregnancy (TTP) is a good indicator with which to reflect human fecundability, and a longer TTP is known to reflect a reduction in fertility. Many original studies, with different designs, have used TTP to explore the factors that might influence fertility, including basic demographic characteristics, chronic disease status, environmental endocrine disruptor exposure, and lifestyles. However, much of the existing evidence is inconsistent and limited by various types of bias. This review provides a synopsis of recent TTP studies, and highlights new opportunities and future challenges.

Family Socioeconomic Position and Lung Cancer Risk: A Meta-Analysis and a Mendelian Randomization Study

Background

Family socioeconomic position (SEP) in childhood is an important factor to predict some chronic diseases. However, the association between family SEP in childhood and the risk of lung cancer is not clear.

Methods

A systematic search was performed to explore their relationship. We selected education level, socioeconomic positions of parents and childhood housing conditions to represent an individual family SEP. Hazard ratios (HRs) of lung cancer specific-mortality were synthesized using a random effects model. Two-sample Mendelian randomization (MR) was carried out with summary data from published genome-wide association studies of SEP to assess the possible causal relationship of SEP and risk of lung cancer.

Results

Through meta-analysis of 13 studies, we observed that to compared with the better SEP, the poorer SEP in the childhood was associated with the increased lung cancer risk in the adulthood (HR: 1.25, 95% CI: 1.10 to 1.43). In addition, the dose-response analysis revealed a positive correlation between the poorer SEP and increased lung cancer risk. Same conclusion was reached in MR [(education level) OR 0.50, 95% CI: 0.39 to 0.63; P &lt; 0.001].

Conclusion

This study indicates that poor family socioeconomic position in childhood is causally correlated with lung cancer risk in adulthood.

Systematic Review Registration

identifier: 159082.

Personalized Nutrition in the Management of Female Infertility: New Insights on Chronic Low-Grade Inflammation

Increasing evidence on the significance of nutrition in reproduction is emerging from both animal and human studies, suggesting a mutual association between nutrition and female fertility. Different “fertile” dietary patterns have been studied; however, in humans, conflicting results or weak correlations are often reported, probably because of the individual variations in genome, proteome, metabolome, and microbiome and the extent of exposure to different environmental conditions. In this scenario, “precision nutrition”, namely personalized dietary patterns based on deep phenotyping and on metabolomics, microbiome, and nutrigenetics of each case, might be more efficient for infertile patients than applying a generic nutritional approach. In this review, we report on new insights into the nutritional management of infertile patients, discussing the main nutrigenetic, nutrigenomic, and microbiomic aspects that should be investigated to achieve effective personalized nutritional interventions. Specifically, we will focus on the management of low-grade chronic inflammation, which is associated with several infertility-related diseases.

The Influence of Diet on Ovulation Disorders in Women—A Narrative Review

Female infertility is commonly due to ovulation disorders. They are mostly related to polycystic ovary syndrome, which is currently viewed as one of the most common endocrine disorders in women of reproductive age. Ovulation-related female fertility is influenced by multiple factors which may include: age, smoking cigarettes, stress, use of psychoactive substances, and physical activity. Moreover, diet-related factors play an important role in the regulation of ovulation. Dietary components that exert a positive influence on ovulation include: carbohydrate products with low glycemic index, plant protein, monounsaturated and polyunsaturated fatty acids, folic acid, vitamin D, antioxidants, and iron. A diet based on the structure of the Mediterranean diet also seems beneficial. Components that have a negative influence mostly include high glycemic index carbohydrates, large amounts of animal protein, saturated fatty acids, and trans fatty acids, which are typically found in the Western model of nutrition. Due to the paucity of studies that presented a direct link between nutrition and the risk of anovulatory infertility, this study aimed to summarize the most recent research on the influence of dietary factors on ovulation disorders and indicate the possibilities of future research.

Predictive models of pregnancy based on data from a preconception cohort study

STUDY QUESTION

Can we derive adequate models to predict the probability of conception among couples actively trying to conceive?

SUMMARY ANSWER

Leveraging data collected from female participants in a North American preconception cohort study, we developed models to predict pregnancy with performance of ∼70% in the area under the receiver operating characteristic curve (AUC).

WHAT IS KNOWN ALREADY

Earlier work has focused primarily on identifying individual risk factors for infertility. Several predictive models have been developed in subfertile populations, with relatively low discrimination (AUC: 59-64%).

STUDY DESIGN, SIZE, DURATION

Study participants were female, aged 21-45 years, residents of the USA or Canada, not using fertility treatment, and actively trying to conceive at enrollment (2013-2019). Participants completed a baseline questionnaire at enrollment and follow-up questionnaires every 2 months for up to 12 months or until conception. We used data from 4133 participants with no more than one menstrual cycle of pregnancy attempt at study entry.

PARTICIPANTS/MATERIALS, SETTING, METHODS

On the baseline questionnaire, participants reported data on sociodemographic factors, lifestyle and behavioral factors, diet quality, medical history and selected male partner characteristics. A total of 163 predictors were considered in this study. We implemented regularized logistic regression, support vector machines, neural networks and gradient boosted decision trees to derive models predicting the probability of pregnancy: (i) within fewer than 12 menstrual cycles of pregnancy attempt time (Model I), and (ii) within 6 menstrual cycles of pregnancy attempt time (Model II). Cox models were used to predict the probability of pregnancy within each menstrual cycle for up to 12 cycles of follow-up (Model III). We assessed model performance using the AUC and the weighted-F1 score for Models I and II, and the concordance index for Model III.

MAIN RESULTS AND THE ROLE OF CHANCE

Model I and II AUCs were 70% and 66%, respectively, in parsimonious models, and the concordance index for Model III was 63%. The predictors that were positively associated with pregnancy in all models were: having previously breastfed an infant and using multivitamins or folic acid supplements. The predictors that were inversely associated with pregnancy in all models were: female age, female BMI and history of infertility. Among nulligravid women with no history of infertility, the most important predictors were: female age, female BMI, male BMI, use of a fertility app, attempt time at study entry and perceived stress.

LIMITATIONS, REASONS FOR CAUTION

Reliance on self-reported predictor data could have introduced misclassification, which would likely be non-differential with respect to the pregnancy outcome given the prospective design. In addition, we cannot be certain that all relevant predictor variables were considered. Finally, though we validated the models using split-sample replication techniques, we did not conduct an external validation study.

WIDER IMPLICATIONS OF THE FINDINGS

Given a wide range of predictor data, machine learning algorithms can be leveraged to analyze epidemiologic data and predict the probability of conception with discrimination that exceeds earlier work.

STUDY FUNDING/COMPETING INTEREST(S)

The research was partially supported by the U.S. National Science Foundation (under grants DMS-1664644, CNS-1645681 and IIS-1914792) and the National Institutes for Health (under grants R01 GM135930 and UL54 TR004130). In the last 3 years, L.A.W. has received in-kind donations for primary data collection in PRESTO from FertilityFriend.com, Kindara.com, Sandstone Diagnostics and Swiss Precision Diagnostics. L.A.W. also serves as a fibroid consultant to AbbVie, Inc. The other authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Female Fertility and the Nutritional Approach: The Most Essential Aspects

Infertility is an increasing problem that affects couples attempting pregnancy. A growing body of evidence points to a link between diet and female fertility. In fact, data show that a diet high in trans fats, refined carbohydrates, and added sugars can negatively affect fertility. Conversely, a diet based on the Mediterranean dietary patterns, i.e., rich in dietary fiber, omega-3 (ɷ-3) fatty acids, plant-based protein, and vitamins and minerals, has a positive impact on female fertility. An unhealthy diet can disrupt microbiota composition, and it is worth investigating whether the composition of the gut microbiota correlates with the frequency of infertility. There is a lack of evidence to exclude gluten from the diet of every woman trying to become pregnant in the absence of celiac disease. Furthermore, there are no data concerning adverse effects of alcohol on female fertility, and caffeine consumption in the recommended amounts also does not seem to affect fertility. On the other hand, phytoestrogens presumably have a positive influence on female fertility. Nevertheless, there are many unanswered questions with regard to supplementation in order to enhance fertility. It has been established that women of childbearing age should supplement folic acid. Moreover, most people experience vitamin D and iodine deficiency; thus, it is vital to control their blood concentrations and consider supplementation if necessary. Therefore, since diet and lifestyle seem to be significant factors influencing fertility, it is valid to expand knowledge in this area.

The association between alcohol intake and fecundability during menstrual cycle phases

STUDY QUESTION

Is increased alcohol intake in different phases of the menstrual cycle associated with fecundability in women?

SUMMARY ANSWER

Heavy intake (>6 drinks/week) of alcoholic beverages in the luteal phase and ovulatory subphase was associated with reduced odds of conception; moderate intake (3-6 drinks/week) during the luteal phase was also associated with reduced fecundability.

WHAT IS KNOWN ALREADY

Despite strong indications for increased risk of infertility among drinking women with intention to conceive, inconsistencies in previous results point to possible residual confounding, and have not thoroughly investigated timing of drinking and other drinking patterns during the menstrual cycle.

STUDY DESIGN, SIZE, DURATION

Participants in The Mount Sinai Study of Women Office Workers (MSSWOW), a prospective cohort study of fertility, were recruited and followed between 1990 and 1994, and completed daily diaries reporting their alcohol intake (type and number of drinks) for a maximum of 19 months of follow-up (N = 413).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were between 19 and 41 years of age. After completion of baseline surveys, they were asked to record their alcoholic beverage intake as number of drinks of beer, wine, and liquor per day, in addition to other exposures such as caffeine and smoking. Furthermore, they submitted urine samples each month to assess pregnancy. Menstrual cycle phases were calculated using the Knaus-Ognio approach. Discrete survival analysis methods were employed to estimate the association between categories of alcohol intake in each phase of menstrual cycle and fecundability.

MAIN RESULTS AND THE ROLE OF CHANCE

In the luteal phase, both moderate drinking (3-6 drinks/week, Fecundability Odds Ratio (FOR)=0.56, CI: 0.31, 0.98) and heavy drinking (>6 drinks/week, FOR = 0.51, CI: 0.29, 0.89) were associated with a reduction in fecundability, compared to non-drinkers. For the follicular phase, heavy drinking in the ovulatory sub-phase (FOR = 0.39, CI: 0.19, 0.72) was similarly associated with reduced fecundability, compared to non-drinkers. For the pre-ovulatory sub-phase, heavy drinking (>6 drinks/week, FOR = 0.54, CI: 0.29, 0.97) was associated with reduction in fecundability, but this association was inconsistent when subjected to sensitivity tests. Each extra day of binge drinking was associated with 19% (FOR = 0.81, CI: 0.63, 0.98), and 41% (FOR = 0.59, CI: 0.33, 0.93) reduction in fecundability for the luteal phase and ovulatory sub-phase respectively, but no association was observed in the pre-ovulatory sub-phase. No meaningful differences in fecundability between beverages were observed in any menstrual phase.

LIMITATIONS, REASONS FOR CAUTION

Patterns of alcohol intake in this cohort suggest a lower average alcohol intake compared to more recent national averages for the same demographic group. Sample sizes were small for some subgroups, resulting in limited power to examine specific beverage types in different phases of the menstrual cycle, or to assess interaction. In addition, the influence of male partner alcohol intake was not assessed, the data relied on self-report, and residual confounding (e.g. unmeasured behaviors correlated with alcohol intake) is a possibility.

WIDER IMPLICATIONS OF THE FINDINGS

Results suggest an inverse association between alcohol and fecundability, and support the relevance of menstrual cycle phases in this link. More specifically, moderate to heavy drinking during the luteal phase, and heavy drinking in the ovulatory window, could disturb the delicate sequence of hormonal events, affecting chances of a successful conception.

STUDY FUNDING/COMPETING INTEREST(S)

Authors declare no conflict of interest. This work was supported by the National Institutes of Health grant, R01-HD24618.

TRIAL REGISTRATION NUMBER

N/A.

Self-reported periodontitis and fecundability in a population of pregnancy planners

STUDY QUESTION

Is a history of periodontitis among women associated with reduced fecundability?

SUMMARY ANSWER

A history of periodontitis, as assessed by three different self-reported measures, may be associated with reduced fecundability.

WHAT IS KNOWN ALREADY

Periodontitis is a chronic inflammatory condition affecting the hard and soft tissues surrounding the teeth. Few studies have evaluated the association between periodontitis and time to pregnancy, and findings are mixed. It is hypothesized that periodontitis may adversely affect time to pregnancy.

STUDY DESIGN, SIZE, DURATION

We conducted a prospective cohort study of 2764 female pregnancy planners residing in North America (March 2015-June 2020).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Eligible participants had been attempting pregnancy for six or fewer menstrual cycles at enrollment and were not using fertility treatment. Women answered questions about their oral health. Pregnancy was ascertained via bi-monthly follow-up questionnaires. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs) for three different measures indicative of a history of periodontitis: ever diagnosed with periodontitis (N = 265), ever received treatment for periodontitis (N = 299), and ever had an adult tooth become loose on its own (N = 83). We adjusted for potential confounders and precision variables. Women at risk of misclassification of periodontitis diagnosis due to pregnancy-related gingivitis were reclassified in a sensitivity analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

All three indices of periodontitis may be associated with reduced fecundability. FRs were 0.89 (95% CI 0.75-1.06) comparing women with and without a previous periodontitis diagnosis, 0.79 (95% CI 0.67-0.94) comparing women with and without previous periodontitis treatment, and 0.71 (95% CI 0.44-1.16) comparing women with and without a tooth that became loose. After reclassification of pregnancy-related gingivitis in the sensitivity analysis, the FR for periodontitis diagnosis was 0.83 (95% CI 0.68-1.00). Weaker FRs were observed among parous women as compared with nulliparous women for periodontitis diagnosis and tooth becoming loose, but not for periodontitis treatment.

LIMITATIONS, REASONS FOR CAUTION

Though we used validated self-report measures of periodontitis, clinical confirmation is the gold standard. These questions may be functioning as markers of different levels of periodontitis severity, but we were unable to measure disease severity in this population. Finally, we cannot eliminate the possibility of unmeasured confounding.

WIDER IMPLICATIONS OF THE FINDINGS

This is the first preconception prospective cohort study to evaluate the association between self-reported periodontitis and fecundability. Our results indicate that periodontitis may be associated with lower fecundability.

STUDY FUNDING/COMPETING INTEREST(S)

This work was partially funded by R01HD086742/Eunice Kennedy Shriver National Institute of Child Health and Human Development and R21HD072326/Eunice Kennedy Shriver National Institute of Child Health and Human Development. PRESTO has received in-kind donations from Swiss Precision Diagnostics, Sandstone Diagnostics, FertilityFriend.com, and Kindara.com for primary data collection. L.A.W. is a fibroid consultant for AbbVie, Inc. J.C.B., S.W., J.Y., K.J.R., E.E.H., and B.H. have no conflicts of interest to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Systematic Review and Dose-Response Meta-Analysis on the Relationship Between Alcohol Consumption and Sickness Absence

AIMS

Alcohol consumption (AC) may cause workplace absence, but the findings of individual studies vary markedly. To date, no dose-response meta-analysis (DRMA) of the relationship between AC and sickness absence (SA) has been completed. This paper aims to estimate the dose-response relationship between AC and the risk of SA based on published observational studies.

METHODS

We used DRMA and modelling to investigate the effects of varying doses of AC (including heavy episodic drinking (HED)) onSA.

RESULTS

The meta-analysis included 21 studies (12 cohort studies and 9 cross-sectional). It showed that HED, risky (20-40 g of alcohol/day) and high-risk (>40 g of alcohol/day) drinkers had an elevated risk of SA when compared with light-to-moderate drinkers for both sexes. Those who abstained from alcohol had a higher risk of SA than those who drink moderately.

CONCLUSIONS

Our results indicate that risky, high-risk drinking and HED may increase the risk of absenteeism. The implementation of population-based strategies may be appropriate to address the burdens of alcohol-related SA. Additionally, economic evaluations of alcohol policies should incorporate their impacts on SA. However, the current literature has substantial limitations, relying on modestly designed studies from just a few settings and more studies are needed-especially those that measure abstention in more nuancedways.

Effects of environmental, social and surgical factors on ovarian reserve: Implications for age-relative female fertility

OBJECTIVE

To investigate new risk factors for female fertility by analyzing the effects of environmental, social, and surgical factors on antral follicle counts (AFC) and anti-Müllerian hormone (AMH) levels.

METHODS

A total of 1513 women aged 20-47 years who underwent in vitro fertilization/intracytoplasmic injection treatment in Southwest Hospital from December 2017 to December 2019 were included. Women were assessed for AFC and AMH levels, and completed a questionnaire. Ordinal logistic regression analyses with generalized linear mixed models were used to calculate the adjusted odds ratio (OR) for diminished ovarian reserve.

RESULTS

Adnexal surgery was the only risk factor associated with low AFC in women aged 20-30 years. Younger age at menarche, alcohol drinking, and adnexal surgery are three independent risk factors for AMH decline in women aged 20-30 years. Intense exercise, sleep quality, and adnexal surgery are three independent risk factors for a low AFC in women aged 31-36 years. Alcohol drinking and adnexal surgery are two independent risk factors for AMH decline in women aged 31-36 years.

CONCLUSION

With age, female fertility becomes sensitive to high-intensity exercise and poor sleep quality. Adnexal surgery and alcohol drinking are two important risk factors for female fertility in women under age 37 years.

Mendelian randomisation approaches to the study of prenatal exposures: A systematic review

BACKGROUND

Mendelian randomisation (MR) designs apply instrumental variable techniques using genetic variants to study causal effects. MR is increasingly used to evaluate the role of maternal exposures during pregnancy on offspring health.

OBJECTIVES

We review the application of MR to prenatal exposures and describe reporting of methodologic challenges in this area.

DATA SOURCES

We searched PubMed, EMBASE, Medline Ovid, Cochrane Central, Web of Science, and Google Scholar.

STUDY SELECTION AND DATA EXTRACTION

Eligible studies met the following criteria: (a) a maternal pregnancy exposure; (b) an outcome assessed in offspring of the pregnancy; and (c) a genetic variant or score proposed as an instrument or proxy for an exposure.

SYNTHESIS

We quantified the frequency of reporting of MR conditions stated, techniques used to examine assumption plausibility, and reported limitations.

RESULTS

Forty-three eligible studies were identified. When discussing challenges or limitations, the most common issues described were known potential biases in the broader MR literature, including population stratification (n = 29), weak instrument bias (n = 18), and certain types of pleiotropy (n = 30). Of 22 studies presenting point estimates for the effect of exposure, four defined their causal estimand. Twenty-four studies discussed issues unique to prenatal MR, including selection on pregnancy (n = 1) and pleiotropy via postnatal exposure (n = 10) or offspring genotype (n = 20).

CONCLUSIONS

Prenatal MR studies frequently discuss issues that affect all MR studies, but rarely discuss problems specific to the prenatal context, including selection on pregnancy and effects of postnatal exposure. Future prenatal MR studies should report and attempt to falsify their assumptions, with particular attention to issues specific to prenatal MR. Further research is needed to evaluate the impacts of biases unique to prenatal MR in practice.

Gender Convergence in Alcohol Consumption Patterns: Findings from the Korea National Health and Nutrition Examination Survey 2007-2016

Gender differences in alcohol use have narrowed over the decades. This study aimed to explore changes in alcohol consumption patterns between 2007 and 2016 to identify gender convergence in alcohol use in Korea. Data from the Korea National Health and Nutrition Examination Survey were used. For all respondents (41,662 girls/women and 32,041 boys/men) aged ≥12 years, lifetime drinking, current drinking, age of drinking onset, heavy alcohol use, and binge drinking were analyzed. Gender differences in heavy alcohol use and binge drinking decreased from 2007 to 2016 (p = 0.001 and p < 0.001, respectively). The prevalence of heavy alcohol use and binge drinking decreased in boys/men (67.5% to 63.9%, p = 0.001; 63.4% to 60.9%, p = 0.001, respectively), but not in girls/women (50.2% to 50.4%, p = 0.279; 30.6% to 32.0%, p = 0.994, respectively). The proportion of lifetime abstainers decreased among both girls/women (24.3% to 19.1%, p < 0.001) and boys/men (12.1% to 9.7%, p = 0.01). In girls/women, the mean age of drinking onset decreased (from 24.1 to 23.6 years, p = 0.017); however, in boys/men, significant changes were not observed (from 18.9 to 18.7 years, p = 0.307). Healthcare providers should be aware of the growing health risks resulting from increased unhealthy alcohol use in women and develop gender-specific preventive interventions.

Pretreatment maternal lifestyle and outcomes of assisted reproduction: an Italian cohort study

OBJECTIVE

We investigated whether lifestyle affects assisted reproduction technology (ART) outcomes.

DESIGN

Cohort study.

SETTING

Italian fertility unit.

PARTICIPANTS

From September 2014 to December 2016, women from couples presenting for evaluation and eligible for ART were invited to participate. Information on alcohol intake, current smoking and leisure physical activity (PA) during the year before the interview was collected, using a structured questionnaire. We considered the ART outcomes of the cycle immediately following the interview.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was cumulative pregnancy rate per retrieval. Secondary measures were number of retrieved oocytes, embryo transfer and live birth.

RESULTS

In 492 women undergoing an ART cycle, 427 (86.8%) underwent embryo transfer, 157 (31.9%) had at least one clinical pregnancy and 121 (24.6%) had live birth. The cumulative pregnancy rate per retrieval was 33.3% (95% CI 28.5% to 38.7%). In women in the third tertile of alcohol intake, adjusted relative risk was 0.97 (95% CI 0.87 to 1.08), 0.90 (95% CI 0.62 to 1.30) and 0.89 (95% CI 0.57 to 1.37) for embryo transfer, clinical pregnancy and live birth, respectively. The corresponding figures in women currently smoking more than 5 cigarettes/day were 1.00 (95% CI 0.88 to 1.16), 0.94 (95% CI 0.60 to 1.48) and 1.14 (95% CI 0.68 to 1.90), and in women with PA ≥5 hours/week were 0.93 (95% CI 0.79 to 1.08), 0.44 (95% CI 0.22 to 0.90) and 0.48 (95% CI 0.22 to 1.05), respectively.

CONCLUSION

There were no significant differences in in vitro fertilisation outcomes among women who used alcohol or tobacco in the year prior to treatment. Conservatively, all women should be advised to limit substance abuse. Moreover, our study suggested that maintaining a moderate, but not high, level of PA could be beneficial.

Alcohol use in pregnancy and its impact on the mother and child

AIMS

To review the impact of prenatal alcohol exposure on the outcomes of the mother and child.

DESIGN

Narrative review.

SETTING

Review of literature.

PARTICIPANTS

Mothers and infants affected by prenatal alcohol use.

MEASUREMENTS

Outcomes of mothers and children.

FINDINGS

Prenatal alcohol exposure is one of the most important causes of preventable cognitive impairment in the world. The developing neurological system is exquisitely sensitive to harm from alcohol and there is now also substantial evidence that alcohol-related harm can extend beyond the individual person, leading to epigenetic changes and intergenerational vulnerability and disadvantage. There is no known safe level or timing of drinking for pregnant or lactating women and binge drinking (> four drinks within 2 hours for women) is the most harmful. Alcohol-exposure increases the risk of congenital problems, including Fetal Alcohol Spectrum Disorder (FASD) and its most severe form, Fetal Alcohol Syndrome (FAS).

CONCLUSION

The impact of FASD and FAS is enduring and life-long with no current treatment or cure. Emerging therapeutic options may mitigate the worst impact of alcohol exposure but significant knowledge gaps remain. This review discusses the history, epidemiology and clinical presentations of prenatal alcohol exposure, focusing on FASD and FAS, and the impact of evidence on future research, practice and policy directions.

Online Japanese-Language Information on Lifestyle Factors Associated With Reduced Fertility: Content Analysis

Background

Approximately one-third of Japanese couples currently worry or previously worried about infertility. To develop strategies for the primary prevention of infertility as a population approach, it is important for the general population to be knowledgeable about fertility and infertility. The internet may contribute to the dissemination of information regarding infertility and fertility. However, few studies have examined online information about fertility.

Objective

This study aimed to quantitatively examine online Japanese-language information about lifestyle factors associated with reduced fertility.

Methods

We conducted online searches, using the 10 search terms with the highest numbers of searches that people hoping to conceive are likely to input in two major search engines in Japan (Google Japan and Yahoo! Japan). From the 2200 retrieved websites, 1181 duplicates and 500 websites unrelated to our objective were excluded, resulting in a final dataset of 519 websites. Coding guidelines were developed for the following lifestyle factors associated with reduced fertility: sexually transmitted diseases, psychological stress, cigarette smoking, alcohol use, nutrition and diet, physical activity and exercise, underweight, overweight and obesity, and environmental pollutants.

Results

In terms of the website author’s professional expertise, 69.6 % of the coding instances for the selected lifestyle factors were mentioned by hospitals, clinics, or the media, whereas only 1.7% were mentioned by laypersons. Psychological stress (20.1%) and sexually transmitted diseases (18.8%) were the most frequently mentioned lifestyle factors associated with reduced fertility. In contrast, cigarette smoking, alcohol use, nutrition and diet, physical activity and exercise, underweight, overweight and obesity, and environmental pollutants were mentioned relatively infrequently. The association between reduced fertility and sexually transmitted diseases was mentioned significantly more frequently by hospitals and clinics than by the media (P<.001). The association between reduced fertility and nutrition and diet was mentioned significantly more frequently by the media than by hospitals and clinics (P=.008). With regard to the sex of the target audience for the information, female-specific references to psychological stress, sexually transmitted diseases, nutrition and diet, underweight, physical activity and exercise, and overweight and obesity were significantly more frequent than were male-specific references to these lifestyle factors (psychological stress: P=.002, sexually transmitted diseases: P<.001, nutrition and diet: P<.001, underweight: P<.001, physical activity and exercise: P<.001, overweight and obesity: P<.001).

Conclusions

Of the lifestyle factors known to be related to reduced fertility, cigarette smoking, alcohol use, and male-specific lifestyle factors are mentioned relatively infrequently in online information sources in Japan, and these factors should be discussed more in information published on websites.

Pregnancy, Fertility, Breastfeeding, and Alcohol Consumption: An Analysis of Framing and Completeness of Information Disseminated by Alcohol Industry-Funded Organizations

Objective:

Alcohol use during pregnancy can harm the developing fetus. The exact amount, pattern, and critical period of exposure necessary for harm to occur are unclear, although official guidance often emphasizes precautionary abstention. The impacts on fertility and breastfeeding are also unclear. Information on alcohol and pregnancy is disseminated by the alcohol industry–funded organizations, and there are emerging concerns about its accuracy, suggesting the need for detailed analysis.

Method:

Information on alcohol consumption in relation to fertility, pregnancy, and breastfeeding was extracted from the websites of 23 alcohol industry–funded bodies (e.g., Drinkaware [United Kingdom] and DrinkWise [Australia]), and 19 public health organizations (e.g., Health.gov and NHS Choices). Comparative qualitative and quantitative analysis of the framing and completeness of this information was undertaken.

Results:

Alcohol industry–funded organizations were statistically significantly less likely than public health websites to provide information on fetal alcohol spectrum disorder and less likely to advise that no amount of alcohol is safe during pregnancy. They were significantly more likely to emphasize uncertainties and less likely to use direct language (e.g., “don’t drink”). Some alcohol industry–funded (and no public health) websites appear to use “alternate causation” arguments, similar to those used by the tobacco industry, to argue for causes of alcohol harms in pregnancy other than alcohol.

Conclusions:

Alcohol industry–funded websites omit and misrepresent the evidence on key risks of alcohol consumption during pregnancy. This may “nudge” women toward continuing to drink during pregnancy. These findings suggest that alcohol industry–funded bodies may increase risk to pregnant women by disseminating misinformation. The public should be made widely aware of the risks of obtaining health information from alcohol industry–funded sources.

Association of Gray Matter and Personality Development With Increased Drunkenness Frequency During Adolescence

IMPORTANCE

Alcohol abuse correlates with gray matter development in adolescents, but the directionality of this association remains unknown.

OBJECTIVE

To investigate the directionality of the association between gray matter development and increase in frequency of drunkenness among adolescents.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed participants of IMAGEN, a multicenter brain imaging study of healthy adolescents in 8 European sites in Germany (Mannheim, Dresden, Berlin, and Hamburg), the United Kingdom (London and Nottingham), Ireland (Dublin), and France (Paris). Data from the second follow-up used in the present study were acquired from January 1, 2013, to December 31, 2016, and these data were analyzed from January 1, 2016, to March 31, 2018. Analyses were controlled for sex, site, socioeconomic status, family history of alcohol dependency, puberty score, negative life events, personality, cognition, and polygenic risk scores. Personality and frequency of drunkenness were assessed at age 14 years (baseline), 16 years (first follow-up), and 19 years (second follow-up). Structural brain imaging scans were acquired at baseline and second follow-up time points.

MAIN OUTCOMES AND MEASURES

Increases in drunkenness frequency were measured by latent growth modeling, a voxelwise hierarchical linear model was used to observe gray matter volume, and tensor-based morphometry was used for gray matter development. The hypotheses were formulated before the data analyses.

RESULTS

A total of 726 adolescents (mean [SD] age at baseline, 14.4 [0.38] years; 418 [58%] female) were included. The increase in drunkenness frequency was associated with accelerated gray matter atrophy in the left posterior temporal cortex (peak: t1,710 = -5.8; familywise error (FWE)-corrected P = 7.2 × 10-5; cluster: 6297 voxels; P = 2.7 × 10-5), right posterior temporal cortex (cluster: 2070 voxels; FWE-corrected P = .01), and left prefrontal cortex (peak: t1,710 = -5.2; FWE-corrected P = 2 × 10-3; cluster: 10 624 voxels; P = 1.9 × 10-7). According to causal bayesian network analyses, 73% of the networks showed directionality from gray matter development to drunkenness increase as confirmed by accelerated gray matter atrophy in late bingers compared with sober controls (n = 20 vs 60; β = 1.25; 95% CI, -2.15 to -0.46; t1,70 = 0.3; P = .004), the association of drunkenness increase with gray matter volume at age 14 years (β = 0.23; 95% CI, 0.01-0.46; t1,584 = 2; P = .04), the association between gray matter atrophy and alcohol drinking units (β = -0.0033; 95% CI, -6 × 10-3 to -5 × 10-4; t1,509 = -2.4; P = .02) and drunkenness frequency at age 23 years (β = -0.16; 95% CI, -0.28 to -0.03; t1,533 = -2.5; P = .01), and the linear exposure-response curve stratified by gray matter atrophy and not by increase in frequency of drunkenness.

CONCLUSIONS AND RELEVANCE

This study found that gray matter development and impulsivity were associated with increased frequency of drunkenness by sex. These results suggest that neurotoxicity-related gray matter atrophy should be interpreted with caution.

Non spontaneous vaginal delivery was associated with lower probability of subsequent fertility

OBJECTIVE

Previous systematic reviews have reported that cesarean birth is associated with reduced rate of subsequent fertility. However, other common mode of delivery was poorly understood. The aim of this study was to systematically investigate the subsequent fertility in patients having different modes of non-spontaneous vaginal delivery, if compared to normal vaginal delivery.

STUDY DESIGNS

Medline (via PubMed), Web of Science, Embase (via Dialog), CENTRAL (via Cochrane Library), ScienceDirect (via Elsevier) and ClinicalTrial.gov were searched up to October 2019, without language restrictions in this systematic review and meta-analysis. Articles assessing the mode of delivery and subsequent fertility were included. Quality assessment was evaluated using the nine-point Newcastle Ottawa Scale by two independent reviewers.

RESULTS

Twenty-one articles, including 4,423,544 women of reproductive age, were included. Results showed that women had a 9% (RR: 0.91 [95 %CI 0.88, 0.94]) lower probability of subsequent fertility in primary cesarean birth group, compared with spontaneous vaginal delivery. Further analysis discovered that a 13 % (0.87, [0.85, 0.90]) lower probability of subsequent fertility was observed in women delivered by emergency cesarean birth, a 14 % (0.86, [0.82, 0.91) lower probability by elective cesarean birth, a 39 % (0.61, [0.57, 0.66]) by maternal-requested cesarean birth, and a 2% (0.98, [0.97, 1.00]) by instrumental vaginal delivery.

CONCLUSIONS

Non-spontaneous vaginal delivery may be associated with lower probability of subsequent fertility. Decision makers and obstetricians should be cautious when choosing the mode of delivery.

Pregnancy, Fertility, Breastfeeding, and Alcohol Consumption: An Analysis of Framing and Completeness of Information Disseminated by Alcohol Industry-Funded Organizations

OBJECTIVE

Alcohol use during pregnancy can harm the developing fetus. The exact amount, pattern, and critical period of exposure necessary for harm to occur are unclear, although official guidance often emphasizes precautionary abstention. The impacts on fertility and breastfeeding are also unclear. Information on alcohol and pregnancy is disseminated by the alcohol industry-funded organizations, and there are emerging concerns about its accuracy, suggesting the need for detailed analysis.

METHOD

Information on alcohol consumption in relation to fertility, pregnancy, and breastfeeding was extracted from the websites of 23 alcohol industry-funded bodies (e.g., Drinkaware [United Kingdom] and DrinkWise [Australia]), and 19 public health organizations (e.g., Health.gov and NHS Choices). Comparative qualitative and quantitative analysis of the framing and completeness of this information was undertaken.

RESULTS

Alcohol industry-funded organizations were statistically significantly less likely than public health websites to provide information on fetal alcohol spectrum disorder and less likely to advise that no amount of alcohol is safe during pregnancy. They were significantly more likely to emphasize uncertainties and less likely to use direct language (e.g., "don't drink"). Some alcohol industry-funded (and no public health) websites appear to use "alternate causation" arguments, similar to those used by the tobacco industry, to argue for causes of alcohol harms in pregnancy other than alcohol.

CONCLUSIONS

Alcohol industry-funded websites omit and misrepresent the evidence on key risks of alcohol consumption during pregnancy. This may "nudge" women toward continuing to drink during pregnancy. These findings suggest that alcohol industry-funded bodies may increase risk to pregnant women by disseminating misinformation. The public should be made widely aware of the risks of obtaining health information from alcohol industry-funded sources.

Functional hypothalamic and drug-induced amenorrhea: an overview

BACKGROUND

Functional hypothalamic amenorrhea (FHA) is a form of chronic anovulation not due to identifiable organic causes and with adverse health consequences. The identification of women with this disorder or the precocious identification of women at risk is based on the knowledge of lifestyle risk factors or behaviors such as stress, weight loss, and excessive physical exercise that are known to negatively impact gonadal axis activity.

METHODS

In this overview, we described the most common forms of FHA, in particular stress-induced amenorrhea and overtraining-induced amenorrhea. In addition, although its mechanisms can differ from those involved in FHA, we reviewed the available literature on drug-induced amenorrhea, highlighting the clear connection between this condition and psychoactive drugs such as antipsychotics, antidepressants and anti-epilectics thus raising concern about the role that the abuse of substances such as opioids or alcohol can possibly have on the growing unexplained infertility of the female population.

Mode of delivery and preterm birth in subsequent births: A systematic review and meta-analysis

Preterm birth continues to be an important problem in modern obstetrics and a large public health concern and is related to increased risk for neonatal morbidity and mortality. The aim of this study was to evaluate the data in the literature to determine the relationships between mode of delivery (cesarean section and vaginal birth) in the first pregnancy and the risk of subsequent preterm birth from a multi-year population based cohorts (PROSPERO registration number: 42018090788). Five electronic databases were searched. Observational studies that provided mode of delivery and subsequent preterm birth were eligible. Ten cohort studies, involving 10333501 women, were included in this study. Compared with vaginal delivery, women delivering by previous cesarean section had a significantly higher risk of preterm birth in subsequent births (RR 1.10, 95%CI 1.01-1.20). After adjusting confounding factors, there was still statistical significance (aRR 1.12, 95%CI 1.01-1.24). However, both before and after adjustment, there was no difference among very preterm birth (RR 1.14, 95%CI 0.90-1.43; aRR 1.16, 95%CI 0.80-1.68; respectively). To the best of our knowledge, this is the first systematic review and meta-analysis that suggests previous cesarean section could increase the risk of preterm birth in subsequent pregnancies. The result could provide policy makers, clinicians, and expectant parents to reduce the occurrence of unnecessary cesarean section.

Do you let me symptomatize? The potential role of cultural values in cross-national variability of mental disorders' prevalence

BACKGROUND

Mental disorders may show inherent cross-national variability in their prevalence. A considerable number of meta-analyses attribute this heterogeneity to the methodological diversity in published epidemiological studies. Cultural values are characteristically not assessed in meta-regression models as potential covariates.

AIM

Our aim was to conduct a meta-regression analysis to explore to what extent certain cultural values and immigration rates (as indicator of cultural diversity) might be associated with the cross-national heterogeneity of prevalence rates.

METHOD

To minimize methodological differences that may exert a confounding effect, prevalence rates were obtained from the World Health Organization's (WHO) World Mental Health Survey Initiative. Cultural indices (overall emancipative values; overall secular values) were collected from the World Value Survey, while immigration rates were registered by utilizing the data of the United Nations' World Population Policies 2005 report.

RESULTS

Meta-regression analysis indicated that overall emancipative values (i.e. promoting self-expression, non-violent protest) showed significant connection with lifetime and last year prevalence of any mood disorders (Z = 4.71, p = .001; Z = 2.35, p = .02) and any internalizing disorders (a merged category that combined mood and anxiety disorders; Z = 2.82, p = .004; Z = 2.34, p = .02). Overall secular values (i.e. rejecting authority and obedience) were negatively associated with last year prevalence of depression (Z = -2.75, p = .06). Multistep regression analysis indicated that immigration rate moderated the connection between cultural values and mental disorders. Countries with higher immigration rates showed higher emancipative and secular values.

CONCLUSION

Our findings might function as potential foundation for formulating hypotheses regarding the cultural context's influence on the population's mental health.

Association between hypertensive disorders complicating pregnancy and risk of placenta accreta: a meta-analysis and systematic review

OBJECTIVE

Previous studies have reported a positive association between hypertensive disorders complicating pregnancy and placenta accreta. However, whether hypertensive disorders complicating pregnancy associated with placenta accreta is still not clear. The objective was to systematically review the literature to determine a possible association between hypertensive disorders complicating pregnancy and placenta accreta.

METHODS

A systematic search of PubMed database, the Cochrane Library, Willy Online Library, and ScienceDirect database through 1st December 2015, was conducted. Two authors independently assessed data extraction and quality of the studies using the Newcastle-Ottawa Scale. Assessment of heterogeneity and analysis of data were operated by Review Manager 5.3.0.

RESULTS

Three studies involving 4174 patients who developed hypertensive disorders complicating pregnancy of a total of 38,004 pregnant women were selected. The result of our meta-analysis revealed that pregnancy induced hypertension was significantly associated with a reduction of placenta accreta (OR = 0.50, 95% CI: 0.30-0.82; heterogeneity: I2 = 13%, p = 0.32).

CONCLUSIONS

Our meta-analysis demonstrated that the risk of placenta accreta is reduced in women with hypertensive disorders complicating pregnancy. Further well-designed studies are warranted to testify the result and explored any potential mechanism association between hypertensive disorders complicating pregnancy and placenta accreta.