Length of Fellowship Training in Population Health Research and Long-term Bibliometric Outcomes.

BACKGROUND: The length of research fellowships, the number of doctorates pursuing them, and the academic job market have changed dramatically in recent years. However, there is limited investigation on attributes of fellowships most relevant to future scientific achievement. We analyzed the association of a modifiable aspect of research training, fellowship length, with future achievement and differences across research discipline in the Division of Intramural Population Health Research (DIPHR), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health. METHODS: Demographics of 88 DIPHR trainees from 1998 to 2016 were collected from publicly available annual reports. Research performance metrics, including total publication count and H index through 2016, were collected via Scopus. We used linear regression models for associations between fellowship length, including both total exposure to research training and duration of postdoctoral training alone, and research performance adjusted for start year, publications at entry, branch (e.g., Biostatistics and Bioinformatics, Epidemiology, and Health Behavior), and mentor seniority. RESULTS: Each additional year of research training in DIPHR was associated with a 15% increase in H index (95% confidence interval [CI] = 3.0, 28.4) and 21% more lifetime publications (95% CI = 3.0, 41.9). Results were similar, although attenuated, when evaluating postdoctoral training alone. Differences by discipline were observed, with the strongest positive associations in the Biostatistics and Bioinformatics and Epidemiology Branches. CONCLUSIONS: Longer training at DIPHR was associated with improved measures of research performance, though this relationship varied by discipline. Additional research is needed to tailor training programs to optimize success of trainees.

Associations Between Preconception Plasma Fatty Acids and Pregnancy Outcomes.

BACKGROUND: Although fatty acids are involved in critical reproductive processes, the relationship between specific fatty acids and fertility is uncertain. We investigated the relationship between preconception plasma fatty acids and pregnancy outcomes. METHODS: We included 1,228 women attempting pregnancy with one to two previous pregnancy losses from the EAGeR trial (2007-2011). Plasma fatty acids were measured at baseline. We used log-binomial regression to assess associations between fatty acids and pregnancy, pregnancy loss, and live birth, adjusting for age, race, smoking, BMI, physical activity, income, parity, treatment arm, and cholesterol. RESULTS: Although total saturated fatty acids (SFAs) were not associated with pregnancy outcomes, 14:0 (myristic acid; relative risk [RR] = 1.10, 95% confidence interval [CI] = 1.02, 1.19, per 0.1% increase) and 20:0 (arachidic acid; RR = 1.05, 95% CI = 1.01, 1.08, per 0.1% increase) were positively associated with live birth. Findings suggested a positive association between total monounsaturated fatty acids (MUFAs) and pregnancy and live birth and an inverse association with loss. Total polyunsaturated fatty acids (PUFAs) were associated with lower probability of pregnancy (RR = 0.97, 95% CI = 0.95, 1.00) and live birth (RR = 0.96, 95% CI = 0.94, 0.99), and increased risk of loss (RR = 1.10, 95% CI = 1.00, 1.20), per 1% increase. Trans fatty acids and n-3 fatty acids were not associated with pregnancy outcomes. CONCLUSIONS: Preconception total plasma MUFAs were positively associated with pregnancy and live birth. PUFAs were inversely associated with pregnancy outcomes. Specific SFAs were associated with a higher probability of live birth. Our results suggest that fatty acids may influence pregnancy outcomes.

The role of aspirin and inflammation on reproduction: the EAGeR trial 1.

Inflammation has been linked to several complications in pregnancy, including pregnancy loss. Due to its anti-inflammatory properties, aspirin, a widely available and inexpensive therapy, has potential to help mitigate the negative effects of inflammation along the reproductive pathway. Therefore, the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial was designed to elucidate whether preconception-initiated daily low-dose aspirin would increase the live birth rate in women with 1-2 prior pregnancy losses and no infertility diagnosis and attempting unassisted conception. Here, we present an overview of the collected findings. Low-dose aspirin was associated with an increased live birth rate among women with a single loss at <20 weeks gestation within the past year. When stratified by tertile of C-reactive protein (CRP), a biomarker of inflammation, treatment with aspirin restored a decrement in the live birth rate in women in the highest CRP tertile (relative risk 1.35, 95% confidence interval 1.08-1.67), increasing to similar rates as women of the lower and mid-CRP tertiles. The same effect modification by inflammation status was observed when examining the effect of low-dose aspirin on offspring sex ratio. These results suggest that inflammation plays an important role in reproduction, and that chronic, low-grade inflammation may be amenable to aspirin treatment.

A prospective study of physical activity and fecundability in women with a history of pregnancy loss.

STUDY QUESTION: Is physical activity (PA) associated with fecundability in women with a history of prior pregnancy loss? SUMMARY ANSWER: Higher fecundability was related to walking among overweight/obese women and to vigorous PA in women overall. WHAT IS KNOWN ALREADY: PA may influence fecundability through altered endocrine function. Studies evaluating this association have primarily utilized Internet-based recruitment and self-report for pregnancy assessment and have yielded conflicting results. STUDY DESIGN, SIZE, DURATION: This is a secondary analysis of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial (2007-2011), a multisite, randomized controlled trial of preconception-initiated low-dose aspirin. PARTICIPANTS/MATERIALS, SETTING, METHODS: Healthy women (n = 1214), aged 18-40 and with 1-2 prior pregnancy losses, were recruited from four US medical centers. Participants were followed for up to six menstrual cycles while attempting pregnancy and through pregnancy for those who became pregnant. Time to hCG detected pregnancy was assessed using discrete-time Cox proportional hazard models to estimate fecundability odds ratios (FOR) adjusted for covariates, accounting for left truncation and right censoring. MAIN RESULTS AND THE ROLE OF CHANCE: The association of walking with fecundability varied significantly by BMI (P-interaction = 0.01). Among overweight/obese women, walking ≥10 min at a time was related to improved fecundability (FOR = 1.82, 95% CI: 1.19, 2.77). In adjusted models, women reporting >4 h/wk of vigorous activity had significantly higher fecundability (FOR = 1.69, 95% CI: 1.24, 2.31) compared to no vigorous activity. Associations of vigorous activity with fecundability were not significantly different by BMI (P-interaction = 0.9). Moderate activity, sitting, and International Physical Activity Questionnaire (IPAQ) categories were not associated with fecundability overall or in BMI-stratified analyses. LIMITATIONS, REASONS FOR CAUTION: Some misclassification of PA levels as determined by the short form of the IPAQ is likely to have occurred, and may have led to non-differential misclassification of exposure in our study. Information on diet and change in BMI was not collected and may have contributed to some residual confounding in our results. The generalizability of our results may be limited as our population consisted of women with a history of one or two pregnancy losses. WIDER IMPLICATIONS OF THE FINDINGS: These findings provide positive evidence for the benefits of PA in women attempting pregnancy, especially for walking among those with higher BMI. Further study is necessary to clarify possible mechanisms through which walking and vigorous activity might affect time-to-pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors report no conflicts of interest in this work. TRIAL REGISTRATION NUMBER: #NCT00467363.

Vitamin D is associated with bioavailability of androgens in eumenorrheic women with prior pregnancy loss.

BACKGROUND: Prior studies have reported mixed results regarding relationships between vitamin D, androgens, and sex hormone-binding globulin in patients with polycystic ovary syndrome. However, less is known regarding these associations in eumenorrheic, premenopausal women. OBJECTIVE: Our objective was to study the relationships between serum vitamin D and androgen biomarkers in eumenorrheic women with a history of pregnancy loss who were attempting pregnancy. STUDY DESIGN: This was an analysis of a cohort of 1191 participants from the Effects of Aspirin in Gestation and Reproduction trial (2006-2012). Participants were attempting to conceive, aged 18-40 years, with 1-2 documented prior pregnancy losses and no history of infertility, and recruited from 4 academic medical centers in the United States. Serum vitamin D (25-hydroxyvitamin D) and hormone concentrations were measured at baseline. RESULTS: Vitamin D concentration was negatively associated with free androgen index (percentage change [95% confidence interval, -5% (-8% to -2%)] per 10 ng/mL increase) and positively associated with sex hormone-binding globulin (95% confidence interval, 4% [2-7%]), although not with total testosterone, free testosterone, or dehydroepiandrosterone sulfate after adjusting for age, body mass index, smoking status, race, income, education, physical activity, and season of blood draw. CONCLUSION: Overall, vitamin D was associated with sex hormone-binding globulin and free androgen index in eumenorrheic women with prior pregnancy loss, suggesting that vitamin D may play a role in the bioavailability of androgens in eumenorrheic women. We are limited in making assessments regarding directionality, given the cross-sectional nature of our study.

Preconception hemoglobin A1c concentration in healthy women is not associated with fecundability or pregnancy loss.

Objective: To examine the relationship of preconception hemoglobin A1c, a marker of cumulative exposure to glucose over the preceding 2-3 months, with time to pregnancy, pregnancy loss, and live birth among fecund women without diagnosed diabetes or other medical diseases. Design: A secondary analysis of a prospective cohort of women participating in the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial. Setting: Four US academic medical centers. Patients: A total of 1,194 healthy women aged 18-40 years with a history of one or two pregnancy losses attempting spontaneous conception were observed for up to six cycles while attempting pregnancy and throughout pregnancy if they conceived. Interventions: Not applicable. Main Outcome Measures: Time to pregnancy, human chorionic gonadotropin pregnancy, clinical pregnancy, pregnancy loss, and live birth. Results: Although increasing preconception A1c level was associated with reduced fecundability (fecundability odds ratio [FOR] per unit increase in A1c 0.74; 95% confidence interval [CI] 0.57, 0.96) in unadjusted models and models adjusted for age, race, smoking and treatment arm (FOR 0.79; 95% CI 0.60, 1.04), results were attenuated after further adjustment for body mass index (FOR 0.91; 95% CI 0.68, 1.21). Preconception A1c levels among women without diagnosed diabetes were not associated with live birth or pregnancy loss. Conclusionss: Among healthy women without diagnosed diabetes, we observed no association of A1c with live birth or pregnancy loss. The association between A1c and fecundability was influenced by body mass index, a strong risk factor for both diabetes and infertility. These data support current recommendations that preconception A1c screening should be reserved for patients with risk factors for diabetes. Clinical Trial Registration Number: ClinicalTrials.gov: NCT00467363.

Association of testosterone and antimüllerian hormone with time to pregnancy and pregnancy loss in fecund women attempting pregnancy.

OBJECTIVE: To examine whether higher T and/or antimüllerian hormone (AMH) was associated with anovulation, time to pregnancy (TTP), or pregnancy loss risk among healthy, fecund women without diagnosed polycystic ovary syndrome. DESIGN: Prospective cohort study conducted as a secondary analysis from the Effects of Aspirin in Gestation and Reproduction randomized trial. SETTING: University medical centers. PATIENT(S): A total of 1,198 healthy, eumenorrheic women aged 18-40 years attempting spontaneous pregnancy with one to two prior pregnancy losses were included. Women were categorized by baseline antimüllerian hormone (AMH), as a surrogate marker of antral follicle count, and T concentrations; the highest quartile for each was "high," and below the top quartile (i.e., lower 75% of values) was "norm," forming four groups: norm T/norm AMH (n = 742), norm T/high AMH (n = 156), high T/norm AMH (n = 157), and high T/high AMH (n = 143). INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Anovulation, pregnancy incidence, TTP, and pregnancy loss incidence. RESULT(S): Women with high T/high AMH had a greater anovulation risk (risk ratio 1.58, 95% confidence interval 1.13-2.22) compared with women with norm T/norm AMH, but with imprecise differences in incidence of pregnancy, TTP, or pregnancy loss. CONCLUSION(S): Women with higher T and AMH had more frequent anovulatory cycles but with marginal impacts on TTP or pregnancy loss. A continuum of mild inefficiency in reproductive function may be related to higher T and AMH, including in fecund women with normal menstrual cycles and no clinical diagnosis of polycystic ovary syndrome, but with unclear effects on fecundability and pregnancy loss. CLINICAL TRIAL REGISTRATION NUMBER: NCT00467363.

Preconception Plasma Phospholipid Fatty Acids and Fecundability.

Context: Fatty acids (FAs) are important for reproductive processes, including steroidogenesis, though associations with fecundability, as measured by time to pregnancy (TTP), are unclear. Objective: To investigate the relationship between preconception plasma phospholipid FA (PPFA) levels and time to human chorionic gonadotropin-pregnancy among women with prior pregnancy loss. Design, Setting, and Participants: Prospective cohort of 1228 women attempting pregnancy (aged 18 to 40 years, with one or two prior pregnancy losses) followed for up to six cycles at four US university medical centers during 2006 to 2012. PPFA levels were measured at baseline. Main Outcome Measures: Associations with fecundability overall and by body mass index (BMI) group after adjusting for confounders were estimated using fecundability odds ratios (FORs) and 95% CIs. False discovery rate (FDR) was used to account for multiple comparisons. Results: Monounsaturated fatty acids (MUFAs) were associated with increased fecundability or shorter TTP [FOR, 1.08 (95% CI, 1.01 to 1.16) per unit increase in percentage of total FAs], whereas polyunsaturated fatty acids (PUFAs) were associated with decreased fecundability or longer TTP [FOR, 0.95 (95% CI, 0.91 to 1.00) per 1% change], though associations only remained significant after FDR adjustment among women with BMI <25 kg/m2. Saturated FA and trans FA were not associated with fecundability. Omega-3 FAs and omega-6 linoleic acid were not associated with fecundability. Conclusion: We observed associations between preconception MUFA and PUFA levels and fecundability among women with normal BMI, highlighting the importance of FA composition among normal-weight women with prior pregnancy loss.

Pilot study of placental tissue collection, processing, and measurement procedures for large scale assessment of placental inflammation.

BACKGROUND: Placental dysfunction is related to many pregnancy complications, but collecting placental specimens for investigation in large scale epidemiologic studies is often infeasible. Standard procedures involving immediate collection after birth and snap freezing are often cost prohibitive. We aimed to collect pilot data regarding the feasibility and precision of a simpler approach, the collection of tissue samples following 24 hours of refrigeration of whole placentae at 4°C, as compared to the "gold standard" of snap freezing excised tissue within 40 minutes of delivery for the assessment of inflammatory cytokines. METHODS: Placentae were collected from 12 women after delivering live-born singleton babies via uncomplicated vaginal delivery. Two placentae were utilized to establish laboratory tissue processing and assay protocols. The other 10 placentae were utilized in a comparison of three tissue collection conditions. Specifically, key inflammatory cytokines were measured in 3 sections, representing three collection conditions. Sections 1 (full thickness) and 2 (excised prior to freezing) were obtained within 40 minutes of delivery and snap frozen in liquid nitrogen, and section 3 (full thickness) was obtained after refrigerating the placenta at 4°C for 24 hours. RESULTS: IL-6, IL-10, and IL-8 all had comparable concentrations and variability overall in all three section types. Levels of tumor necrosis factor alpha (TNF-α) were too low among samples to reliably measure using immunoassay. CONCLUSIONS: Refrigeration of placentae prior to processing does not appear to compromise detection of these cytokines for purposes of large scale studies. These findings provide a framework and preliminary data for the study of inflammatory cytokines within the placenta in large scale and/or resource-limited settings.