Dietary fat intake and reproductive hormone concentrations and ovulation in regularly menstruating women

BACKGROUND

Emerging evidence suggests potential links between some dietary fatty acids and improved fertility, because specific fatty acids may affect prostaglandin synthesis and steroidogenesis.

OBJECTIVE

The objective of this exploratory study was to evaluate associations between total and specific types of dietary fat intake and 1) hormone concentrations and 2) the risk of sporadic anovulation in a cohort of 259 regularly menstruating women in the BioCycle Study.

DESIGN

Endogenous reproductive hormones were measured up to 8 times/cycle for up to 2 cycles, with visits scheduled with the use of fertility monitors. Dietary intake was assessed with up to four 24-h recalls/cycle. Linear mixed models and generalized linear models were used to evaluate the associations between dietary fatty acids and both reproductive hormone concentrations and ovulatory status. All models were adjusted for total energy intake, age, body mass index, and race.

RESULTS

Relative to the lowest levels of percentage of energy from total fat, the highest tertile was associated with increased total and free testosterone concentrations (total: percentage change of 4.0%; 95% CI: 0.7%, 7.3%; free: percentage change of 4.1%; 95% CI: 0.5%, 7.7%). In particular, the percentage of energy from polyunsaturated fatty acids (PUFAs) in the highest tertile was associated with increases in total and free testosterone (total: percentage change of 3.7%; 95% CI: 0.6%, 6.8%; free: percentage change of 4.0%; 95% CI: 0.5%, 7.5%). The PUFA docosapentaenoic acid (22:5n-3) was not significantly associated with testosterone concentrations (P-trend = 0.86 in energy substitution models) but was associated with increased progesterone and a reduced risk of anovulation (highest tertile compared with the lowest tertile: RR: 0.42; 95% CI: 0.18, 0.95). Fat intakes were not associated with other reproductive hormone concentrations.

CONCLUSIONS

These results indicate that total fat intake, and PUFA intake in particular, is associated with very small increases in testosterone concentrations in healthy women and that increased docosapentaenoic acid was associated with a lower risk of anovulation.

Modification of the Associations Between Duration of Oral Contraceptive Use and Ovarian, Endometrial, Breast, and Colorectal Cancers

IMPORTANCE

Although oral contraceptive (OC) use is common, the influence of OC use on carcinogenesis is not fully understood. A recent Agency for Healthcare Research and Quality report identified a need to understand the consistency of OC use and cancer associations across subpopulations, including smokers and obese women.

OBJECTIVE

To determine whether associations between duration of OC use and risk of specific cancers were modified by lifestyle characteristics.

DESIGN, SETTING, AND PARTICIPANTS

The prospective NIH-AARP Diet and Health Study (enrolled 1995-1996, followed until 2011), with population-based recruitment of AARP members in 6 states and 2 metropolitan areas. All analyses included at least 100 000 women who reported OC use at enrollment. We identified 1241 ovarian, 2337 endometrial, 11 114 breast, and 3507 colorectal cancer cases during follow-up. Data analysis was performed between September 2016 and April 2017.

EXPOSURES

Duration of OC use (never or <1 year [reference], 1-4, 5-9, or ≥10 years).

MAIN OUTCOMES AND MEASURES

Development of ovarian, endometrial, breast, and colorectal cancers. We examined effect modification by modifiable lifestyle characteristics: cigarette smoking, alcohol consumption, body mass index (BMI), and physical activity. We used Cox models adjusted for age, race, age at menarche, and the modifiers of interest.

RESULTS

The analytic population was aged 50 to 71 years (median, 62 years) at enrollment and largely white (91%) and postmenopausal (96%). For ovarian cancer, OC use-associated risk reductions strengthened with duration of use (long-term OC use [≥10 years] HR, 0.60; 95% CI, 0.47-0.76; P < .001 for trend) and were similar across modifiable lifestyle factors. Risk reductions for endometrial cancer strengthened with duration of use (long-term OC use HR, 0.66; 95% CI, 0.56-0.78; P < .001 for trend); the most pronounced reductions were among long-term OC users who were smokers (HR, 0.47; 95% CI, 0.25-0.88), had obese BMIs (0.36; 95% CI, 0.25-0.52), and who exercised rarely (HR, 0.40; 95% CI, 0.29-0.56). Associations between OC use and breast and colorectal cancers were predominantly null.

CONCLUSIONS AND RELEVANCE

Long-term OC use is consistently associated with reduced ovarian cancer risk across lifestyle factors. We observed the greatest risk reductions for endometrial cancer among women at risk for chronic diseases (ie, smokers, obese BMI). Oral contraceptive use may be beneficial for chemoprevention for a range of women with differing baseline cancer risks.

Serum Antioxidants Are Associated with Serum Reproductive Hormones and Ovulation among Healthy Women

BACKGROUND

Evidence is growing that the equilibrium between reactive oxygen species and antioxidants plays a vital role in women's reproductive health.

OBJECTIVE

The objective of this study was to evaluate variations in serum antioxidant concentrations across the menstrual cycle and associations between antioxidants and reproductive hormones and anovulation among healthy women.

METHODS

The BioCycle Study, a prospective cohort, followed 259 women aged 18-44 y for up to 2 menstrual cycles. Serum fat-soluble vitamin and micronutrient (α-tocopherol, γ-tocopherol, retinol, lutein, lycopene, and β-carotene), ascorbic acid, and reproductive hormone concentrations were measured 5-8 times/cycle. We used weighted linear mixed models to assess associations between antioxidants and hormone concentrations, after adjustment for age, race, body mass index, parity, sleep, pain medication use, total energy intake, concurrent hormones, serum cholesterol, F2-isoprostanes, and other antioxidants. Generalized linear models were used to identify associations with anovulation.

RESULTS

Serum antioxidant concentrations varied across the menstrual cycle. Retinol and α-tocopherol were associated with higher estradiol [RR: 1.00 pg/mL (95% CI: 0.67, 1.34 pg/mL); RR: 0.02 pg/mL (95% CI: 0.003, 0.03 pg/mL), respectively] and testosterone [RR: 0.61 ng/dL (95% CI: 0.44, 0.78 ng/dL); RR: 0.01 ng/dL (95% CI: 0.001, 0.01 ng/dL), respectively]. Ascorbic acid was associated with higher progesterone (RR: 0.15 ng/mL; 95% CI: 0.05, 0.25 ng/mL) and with lower follicle-stimulating hormone (RR: -0.06 mIU/mL; 95% CI: -0.09, -0.03 mIU/mL). The ratio of α- to γ-tocopherol was associated with an increased risk of anovulation (RR: 1.03; 95% CI: 1.01, 1.06).

CONCLUSIONS

These findings shed new light on the intricate associations between serum antioxidants and endogenous hormones in healthy premenopausal women and support the hypothesis that concentrations of serum vitamins affect steroidogenesis even after adjustment for oxidative stress.

The influences of sleep duration, chronotype, and nightwork on the ovarian cycle

Despite research indicating that sleep disorders influence reproductive health, the effects of sleep on reproductive hormone concentrations are poorly characterized. We prospectively followed 259 regularly menstruating women across one to two menstrual cycles (the BioCycle Study, 2005-2007), measuring fasting serum hormone concentrations up to eight times per cycle. Women provided information about daily sleep in diaries and chronotype and night/shift work on a baseline questionnaire. We evaluated percent differences in mean hormone concentrations, the magnitude of shifts in the timing and amplitude of hormone peaks, and the risk for sporadic anovulation associated with self-reported sleep patterns and night/shift work. We estimated chronotype scores - categorizing women below and above the interquartile range (IQR) as "morning" and "evening" chronotypes, respectively. For every hour increase in daily sleep duration, mean estradiol concentrations increased by 3.9% (95% confidence interval [CI] 2.0, 5.9%) and luteal phase progesterone by 9.4% (CI 4.0, 15.2%). Receiving less than 7 hours of sleep per day was associated with slightly earlier rises in peak levels for several hormones. Women reporting night/shift work (n = 77) had lower testosterone relative to women employed without night/shift work (percent difference: -9.9%, CI -18.4, -0.4%). Women with morning chronotypes (n = 47) had earlier rises in estradiol during their cycles and potentially an earlier rise in luteinizing hormone. Compared to those who had intermediate chronotypes, women with evening chronotypes (n = 42) had a later luteinizing hormone peak of borderline statistical significance. A reduced risk for sporadic anovulation was suggested, but imprecise, for increasing hours of daily sleep leading up to ovulation (risk ratio 0.79, CI 0.59, 1.06), while an imprecise increased risk was observed for women with morning chronotypes (risk ratio 2.50, CI 0.93, 6.77). Sleep-related hormonal changes may not greatly alter ovarian function in healthy women, but have the potential to influence gynecologic health.

Breastfeeding and motor development in term and preterm infants in a longitudinal US cohort

Background: The relation between breastfeeding and early motor development is difficult to characterize because of the problems in existing studies such as incomplete control for confounding, retrospective assessment of infant feeding, and even the assessment of some motor skills too early.Objective: We sought to estimate associations between infant feeding and time to achieve major motor milestones in a US cohort.Design: The Upstate New York Infant Development Screening Program (Upstate KIDS Study) enrolled mothers who delivered live births in New York (2008-2010). Mothers of 4270 infants (boys: 51.7%) reported infant motor development at 4, 8, 12, 18, and 24 mo postpartum; information on infant feeding was reported at 4 mo. Accelerated failure time models were used to compare times to standing or walking across feeding categories while adjusting for parental characteristics, daycare, region, and infant plurality, sex, rapid weight gain, and baseline neurodevelopmental test results. Main models were stratified by preterm birth status.Results: The prevalence of exclusive breastfeeding in preterm infants was lower than in term infants at 4 mo postpartum (8% compared with 19%). After adjustment for confounders, term infants who were fed solids in addition to breast milk at 4 mo postpartum achieved both standing [acceleration factor (AF): 0.93; 95% CI: 0.87, 0.99] and walking (AF: 0.93; 95% CI: 0.88, 0.98) 7% faster than did infants who were exclusively breastfed, but these findings did not remain statistically significant after correction for multiple testing. We did not identify feeding-associated differences in motor milestone achievement in preterm infants.Conclusion: Our results suggest that differences in feeding likely do not translate into large changes in motor development. The Upstate KIDS Study was registered at clinicaltrials.gov as NCT03106493.

BET1L and TNRC6B associate with uterine fibroid risk among European Americans

Uterine fibroid (UFs) affect 77 % of women by menopause and account for $9.4 billion in healthcare costs each year. Although UFs are heritable, genetic risk is poorly understood. The first genome-wide association study (GWAS) of UFs was recently performed in a Japanese population, with reported genome-wide significance for single nucleotide polymorphisms (SNPs) across three chromosomal regions. We tested these SNPs for association with UFs in US cohorts. Women were enrolled in the Right from the Start (RFTS) cohort and the BioVU DNA repository. UF status in both cohorts was determined by pelvic imaging. We tested 65 candidate and haplotype-tagging SNPs for association with UFs presence using logistic regression in RFTS and the top three GWAS-associated SNPs in BioVU. We also combined association results from both cohorts using meta-analysis. 1,086 European American (EA) cases and 1,549 controls were examined. Two SNP associations replicated [blocked early in transport 1 homolog (BET1L) rs2280543, RFTS-BioVU meta-odds ratio (OR) = 0.67 95 % confidence interval (CI) 0.38-0.96, Q = 0.70, I = 0, p = 6.9 × 10⁻³; trinucleotide repeat containing 6B (TNRC6B) rs12484776, RFTS-BioVU meta-OR = 1.21, 95 % CI 1.07-1.35, Q = 0.24, I = 28.37, p = 8.7 × 10⁻³). Meta-analyses combining evidence from RFTS, BioVU, and prior GWAS showed little heterogeneity in effect sizes across studies, with meta-p values between 7.45 × 10⁻⁸ and 3.89 × 10⁻⁹, which were stronger than prior GWAS and supported associations observed for all previously identified loci. These data suggest common variants increase risk for UF in both EA and Japanese populations. However, further research is needed to assess the role of these genes across other racial groups.

Postmenopausal Androgen Metabolism and Endometrial Cancer Risk in the Women's Health Initiative Observational Study

Background

After menopause, several androgens continue to be produced primarily by the adrenal glands; these can be converted into estrogens via aromatization or into androgen metabolites. It is unclear if androgens are associated with endometrial cancer risk independently of their being precursors to estrogens or if alternative metabolic pathways influence risk.

Methods

We measured prediagnostic serum concentrations of 12 androgens and their metabolites using highly sensitive liquid chromatography-tandem mass spectrometry assays in a nested case-control study of postmenopausal women from the Women's Health Initiative Observational Study (313 endometrial cancer case subjects, 354 matched control subjects). Estrogens were previously assayed. We used conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for endometrial cancer with adjustment for confounders.

Results

Compared to the lowest concentrations, the highest levels of adrenal androgens were associated with increased endometrial cancer risk: dehydroepiandrosterone (5th vs 1st quintile: OR = 1.85, 95% CI = 1.06 to 3.25), androstenedione (OR = 2.36, 95% CI = 1.34 to 4.16), and testosterone (OR = 1.91, 95% CI = 1.12 to 3.24). Downstream androgen metabolites were not associated with endometrial cancer. Although increased risks for the parent androgens were still suggested after adjustment for unconjugated estradiol, the associations attenuated, and with the exception of androstenedione, were no longer statistically significant. We also evaluated ratios of estrogens relative to their androgenic precursors; both higher unconjugated estrone:androstenedione and higher unconjugated estradiol:testosterone were associated with increased endometrial cancer risk.

Conclusions

We identified increased risks for endometrial cancer with the highest levels of adrenal androgens and high levels of estrogens relative to these androgens. As adrenal androgens can be aromatized to estrogens, this suggests androgens likely influence endometrial carcinogenesis via estrogen metabolism.

Uterine leiomyomata and cesarean birth risk: a prospective cohort with standardized imaging

PURPOSE

To determine if women with leiomyomata detected using uniform ultrasound methods are at increased risk of cesarean birth, without regard to indication.

METHODS

Women were enrolled in Right from the Start (2000-2010), a prospective pregnancy cohort. Leiomyomata were counted, categorized, and measured during first trimester ultrasounds. Women provided information about demographics and reproductive history during first trimester interviews. Route of delivery was extracted from medical records or vital records, if the former were unavailable. Generalized estimating equations were used to calculate risk ratios (RR) and 95% confidence intervals (CIs) for the risk of cesarean birth by leiomyoma presence and characteristics.

RESULTS

Among 2635 women, the prevalences of leiomyomata and cesarean birth were 11.2% and 29.8%, respectively. Women with leiomyomata, compared with those without, had a 27% increase in cesarean risk (RR, 1.27; CI, 1.17-1.37). The association was weaker following adjustment for maternal body mass index and age (adjusted risk ratio [ARR], 1.11; CI, 1.02-1.20). The adjusted risk was elevated for women with a single leiomyoma 3 cm or more in diameter (ARR, 1.22; CI, 1.14-1.32) and women with the largest total leiomyoma volumes (ARR, 1.59; CI, 1.44-1.76).

CONCLUSIONS

Women with leiomyomata were at increased risk for cesarean birth particularly, those with larger tumor volumes.

Folate, homocysteine and the ovarian cycle among healthy regularly menstruating women

STUDY QUESTION

How are concentrations of plasma homocysteine and serum folate associated with reproductive hormones and anovulation in regularly menstruating women?

SUMMARY ANSWER

Higher homocysteine was associated with sporadic anovulation and hormonal changes that may be indicative of impaired ovulatory function, but higher serum folate was associated only with higher luteal phase progesterone.

WHAT IS KNOWN ALREADY

Higher folate levels as well as some variants in genes relevant to one-carbon metabolism, are associated with improved reproductive outcomes and responses to fertility treatment, but only a few small studies have explored the relationship between markers of one-carbon metabolism and menstrual cycle characteristics.

STUDY DESIGN, SIZE, DURATION

The BioCycle Study (2005-2007) is a prospective, longitudinal cohort of 259 regularly menstruating women not using hormonal contraceptives or dietary supplements who were followed for up to two menstrual cycles.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Serum folate and reproductive hormones were measured up to eight times per cycle and plasma homocysteine up to three times. Linear mixed models were used to estimate associations between serum folate or plasma homocysteine and log-transformed reproductive hormone levels while accounting for multiple observations and cycles per woman. Generalized estimating equations were used to examine risk of sporadic anovulation. All models were adjusted for age, race, body mass index, cigarette and alcohol use, and energy and fiber intake.

MAIN RESULTS AND THE ROLE OF CHANCE

Higher plasma homocysteine concentrations were associated with lower total estradiol across the cycle (adjusted percent change per unit increase in homocysteine [aPC] -2.3%, 95% CI: -4.2, -0.03), higher follicle stimulating hormone around the time of expected ovulation (aPC 2.4%, 95% CI: 0.2, 4.7) and lower luteal phase progesterone (aPC -6.5%, 95% CI: -11.1, -1.8). Higher serum folate concentrations were associated with higher luteal phase progesterone (aPC per unit increase in folate 1.0%, 95% CI: 0.4, 1.6). Higher homocysteine concentrations at expected ovulation were associated with a 33% increased risk of sporadic anovulation. We observed no risk associated with decreased folate concentrations, but a higher ratio of folate to homocysteine at ovulation was associated with a 10% decreased risk of anovulation.

LIMITATIONS, REASONS FOR CAUTION

Our results are generalizable to healthy women with adequate serum folate levels. The independent influence of homocysteine should be confirmed in larger cohorts and among women with folate deficiency or increased risks of anovulation.

WIDER IMPLICATIONS OF THE FINDINGS

If these findings are confirmed, it is possible that lowering homocysteine with B-vitamins through diet or supplementation could improve ovulatory function in some women.

Study FUNDING/COMPETING INTEREST(S)

This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (Contract numbers: HHSN275200403394C, HHSN275201100002I and Task one HHSN27500001). None of the authors has any conflicts of interest to disclose.

Trends in oral contraceptive and intrauterine device use among reproductive-aged women in the US from 1999 to 2017

PURPOSE

Since the 1960s, increasing oral contraceptive (OC) use has mirrored decreasing ovarian cancer incidence. The impact of intrauterine devices (IUDs) on cancer risk is less well established. With improved access and increased options, we must consider how changing usage can affect cancer risks.

METHODS

Nationally representative data from the National Health and Nutrition Examination Survey (NHANES, 1999-2016) and the National Survey for Family Growth (NSFG, 2006-2017) were used to evaluate contraceptive use over time in premenopausal women (NHANES n = 13,179; NSFG n = 26,262). Trends were assessed overall and by race, age, pregnancy history, education, and body mass index.

RESULTS

The average annual absolute increase in self-reported IUD use was 0.81% (NSFG), while OC use decreased 0.49% in NSFG and 0.47% in NHANES. This represents a significant decrease in OC use in NSFG [annual percent change (APC) - 2.2% (95% CI - 3.4, - 1.0%), p < 0.01]. Trends in OC use varied somewhat by pregnancy history in NHANES (p-interaction = 0.054). In contrast, IUD use increased 6.2% annually [(1.4, 11.2%), p = 0.03] and varied significantly by pregnancy history (p-interaction < 0.01). Nulligravid women increased IUD use 11.0% annually [(2.6, 20.1%), p = 0.02] compared to women with prior pregnancy at 5.2% [(0.4, 10.2%), p = 0.04]. In 2015-2017, IUD use was 76.5% hormonal (71.1, 81.8%) and 22.9% copper (17.4, 28.3%) with greater hormonal IUD use in obese women [89.4%, (82.9, 95.9%)].

CONCLUSION

Increasing IUD use outpaced declining OC use in premenopausal US women. There may be a resulting decreased gynecologic cancer risk as more women gain access to potentially risk-reducing contraceptives.

Dairy Food Intake Is Associated with Reproductive Hormones and Sporadic Anovulation among Healthy Premenopausal Women

BACKGROUND

Dairy food intake has been associated with infertility; however, little is known with regard to associations with reproductive hormones or anovulation.

OBJECTIVE

We investigated whether intakes of dairy foods and specific nutrients were associated with reproductive hormone concentrations across the cycle and the risk of sporadic anovulation among healthy women.

METHODS

We prospectively measured serum reproductive hormones ≤8 times/menstrual cycle for 2 cycles from 259 regularly menstruating women (mean age: 27.3 y). Dairy food intake was assessed via 24-h dietary recalls 4 times/cycle. Dairy food intakes were assessed by 1) total and low- and high-fat dairy products; 2) dairy nutrients, including fat, lactose, calcium, and phosphorus; and 3) dairy foods, including milk, cheese, butter, cream, yogurt, and ice cream categories. Weighted linear mixed models were used to evaluate associations between dairy nutrients or food intakes and hormone concentrations. Modified Poisson regression models with robust error variance were used to evaluate anovulation. Models were adjusted for age, body mass index, race, physical activity, Mediterranean diet score, total energy, protein, fiber, caffeine, and other hormones.

RESULTS

Each serving increase in total and low- and high-fat dairy foods and all increases in amounts of all dairy nutrients tested were associated with an ∼5% reduction in serum estradiol concentrations but were not associated with anovulation. Total and high-fat dairy food intakes were positively associated with serum luteinizing hormone concentrations. We observed associations between intakes of >0 servings of yogurt (RR: 2.1; 95% CI: 1.2, 3.7) and cream (RR: 1.8; 95% CI: 1.0, 3.2) and a higher risk of sporadic anovulation compared with no intake.

CONCLUSIONS

Our study showed associations between increasing dairy food and nutrient intakes and decreasing estradiol concentrations as well as between cream and yogurt intakes and the risk of sporadic anovulation. These results highlight the potential role of dairy in reproductive function in healthy women.

Maternal Smoking and Newborn Cytokine and Immunoglobulin Levels

INTRODUCTION

Prenatal smoking exposure may lead to permanent changes in neonatal inflammation and immune response that have lifelong implications, including increased risks for atopy and respiratory disorders.

METHODS

The effect of maternal smoking on neonatal biomarkers of inflammation and immune response was assessed among 3459 singletons and twins in the Upstate KIDS Study. The following inflammatory biomarkers were measured using newborn dried blood spots (DBSs): interleukin (IL)-1α, IL-1 receptor antagonist, IL-6, IL-8, C-reactive protein, and tumor necrosis factor alpha. Immunoglobulins (IgE, IgA, IgM, and IgG subclasses) were also assessed. We used generalized estimating equations to calculate mean differences (β) in biomarker levels by timing of pregnancy smoking, cigarette load, and secondhand smoke exposure after adjusting for sociodemographic and lifestyle factors including maternal body mass index.

RESULTS

Of the 344 (12%) women reporting smoking during pregnancy, about 40% continued throughout pregnancy and 13% reported smoking more than 1 pack per day. After covariate adjustment and Bonferroni correction for multiple comparisons, maternal smoking throughout pregnancy remained significantly associated with increased levels of IL-8 (β = 0.20, 95% confidence interval: 0.07, 0.32; p < .003). No significant associations were found with cigarette load or secondhand smoke exposure. Higher IgG3 levels were also associated with maternal smoking throughout pregnancy, although the association became nominally significant after adjustment for covariates (β = 0.09; 95% confidence interval: 0.0007, 0.17; p < .05).

CONCLUSIONS

Maternal smoking throughout pregnancy was independently associated with increased IL-8 levels in newborns. Importantly, neonates of women who stopped smoking anytime in pregnancy did not have increased IL-8 levels.

IMPLICATIONS

This study evaluated a range of inflammatory biomarkers and immunoglobulins in association with maternal smoking and timing/duration of smoking along with secondhand smoke exposure. By using DBSs, we present data from a large cohort of children born in Upstate New York. Our findings suggest that early differences in immunoregulation of neonates exposed to maternal smoking for full duration in utero may already be detected at birth.

Oral Contraceptive Use and Risks of Cancer in the NIH-AARP Diet and Health Study

Although use of oral contraceptives (OCs) is common, their influence on carcinogenesis is not fully understood. We used Cox proportional hazards models to examine OC use (never/<1 year (referent), 1-4, 5-9, ≥10 years) and development of incident cancers across body sites within the same base population: women in the prospective National Institutes of Health-AARP Diet and Health Study (enrolled 1995-1996 and followed until 2011). Adjustment for confounding varied by outcome; all models accounted for age, race, body mass index, and smoking status, and included at least 100,000 women. Any OC use conferred a 3% reduction in the risk for any cancer (hazard ratio = 0.97, 95% confidence interval: 0.95, 0.99). Expected risk reductions that strengthened with duration of use were identified for ovarian and endometrial cancers and were suggested for kidney cancer (all P for trend < 0.05). Non-Hodgkin lymphoma risk (hazard ratio = 0.79, 95% confidence interval: 0.64, 0.97) was reduced with 10 or more years of OC use. There was a 37% reduced risk for bladder cancer and 46% increased risk for pancreatic cancer among long-term OC users who were 60 years of age or younger at baseline. OC use did not influence risks for most other cancers evaluated. Given the high prevalence of use and changing formulations, additional studies are warranted to fully understand the chemopreventive effects of these medications.

Preconception care: it's never too early

The preconception window has been recognized as one of the earliest sensitive windows of human development, and interventions that focus on this period have the potential to affect not only pregnancy but long term outcomes as well. The journal Reproductive Health has published a supplement entitled 'Preconception Interventions' which includes a series of systematic reviews regarding the impact of public health interventions during the preconception period on maternal and child health. These articles describe the role that poor preconception health plays in creating health disparities across the globe. The reviews highlight our current understanding (or lack thereof) regarding how both maternal and paternal preconception health and knowledge shapes the long-term health of not only children, but of families, communities, and nations. Researchers and healthcare workers should take particular note of these interventions, as the preconception time period may be as important as the pregnancy and post-pregnancy periods, and is critical in terms of bridging the gap in the continuum of care, particularly for adolescents.

Circulating androgens and postmenopausal ovarian cancer risk in the Women's Health Initiative Observational Study

Our knowledge of epidemiologic risk factors for ovarian cancer supports a role for androgens in the pathogenesis of this disease; however, few studies have examined associations between circulating androgens and ovarian cancer risk. Using highly sensitive LC-MS/MS assays, we evaluated associations between pre-diagnostic serum levels of 12 androgens, including novel androgen metabolites that reflect androgen activity in tissues, and ovarian cancer risk among postmenopausal women in a nested case-control study in the Women's Health Initiative (WHI) Observational Study (OS). We frequency-matched 169 ovarian cancer cases to 410 controls from women enrolled in WHI-OS who were not using menopausal hormones at enrollment/blood draw. We estimated associations overall and by subtype (n = 102 serous/67 non-serous) using multivariable adjusted logistic regression. Androgen/androgen metabolite levels were not associated with overall ovarian cancer risk. In analyses by subtype, women with increased levels of androsterone-glucuronide (ADT-G) and total 5-α reduced glucuronide metabolites (markers of tissue-level androgenic activity) were at increased risk of developing non-serous ovarian cancer: ADT-G tertile (T)3 versus T1 odds ratio [OR] (95% confidence interval [CI]) 4.36 (1.68-11.32), p-heterogeneity 0.002; total glucuronide metabolites 3.63 (1.47-8.95), 0.002. Risk of developing serous tumors was unrelated to these markers. ADT-G and total glucuronide metabolites, better markers of tissue-level androgenic activity in women than testosterone, were associated with an increased risk of developing non-serous ovarian cancer. Our work demonstrates that sex steroid metabolism is important in the etiology of non-serous ovarian cancers and supports a heterogeneous hormonal etiology across histologic subtypes of ovarian cancer.

Metabolic syndrome and risk of ovarian and fallopian tube cancer in the United States: An analysis of linked SEER-Medicare data

OBJECTIVE

To clarify associations between metabolic syndrome, its components, and ovarian cancer risk.

METHODS

Using a case-control study within the U.S.-based Surveillance, Epidemiology and End Results (SEER)-Medicare linked database, we examined metabolic syndrome, its components (obesity, impaired fasting glucose, hypertension, HDL cholesterol, triglycerides), and ovarian/fallopian tube cancer risk. Cases (n = 16,850) were diagnosed with cancer between age 68-89 from 1994 through 2013. Controls (n = 281,878) were Medicare enrollees without these cancers living in registry areas. We estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) with logistic regression.

RESULTS

Women with metabolic syndrome had reduced ovarian cancer risk compared to women not meeting the diagnostic criteria (OR 0.86, CI 0.82-0.89). Having one or two syndrome components was associated with increased risk, but having ≥3 was not, when compared to women without any components. Impaired fasting glucose, which was highly prevalent among those with metabolic syndrome, was associated with reduced risk (OR 0.90, CI 0.87-0.93). Hypertension and high triglycerides, the most prevalent components among women without metabolic syndrome, were associated with increased risks (OR 1.08, CI 1.04-1.12; OR 1.05, CI 1.01-1.08, respectively).

CONCLUSIONS

Specific metabolic syndrome components may have modest associations with ovarian cancer. These associations varied in direction and the prevalence of the components influenced the overall association between metabolic syndrome and ovarian cancer. Evaluating metabolic syndrome as a composite exposure could be misleading in ovarian cancer research, but further study of the syndrome components is warranted.

Dietary minerals, reproductive hormone levels and sporadic anovulation: associations in healthy women with regular menstrual cycles

Although minerals are linked to several reproductive outcomes, it is unknown whether dietary minerals are associated with ovulatory function. We hypothesised that low intakes of minerals would be associated with an increased risk of anovulation. We investigated associations between dietary mineral intake and both reproductive hormones and anovulation in healthy women in the BioCycle Study, which prospectively followed up 259 regularly menstruating women aged 18-44 years who were not taking mineral supplements for two menstrual cycles. Intakes of ten selected minerals were assessed through 24-h dietary recalls at up to four times per cycle in each participant. Oestradiol, progesterone, luteinising hormone (LH), follicle-stimulating hormone (FSH), sex-hormone-binding globulin and testosterone were measured in serum up to eight times per cycle. We used weighted linear mixed models to evaluate associations between minerals and hormones and generalised linear models for risk of anovulation. Compared with Na intake ≥1500 mg, Na intake <1500 mg was associated with higher levels of FSH (21·3 %; 95 % CI 7·5, 36·9) and LH (36·8 %; 95 % CI 16·5, 60·5) and lower levels of progesterone (-36·9 %; 95 % CI -56·5, -8·5). Na intake <1500 mg (risk ratio (RR) 2·70; 95 % CI 1·00, 7·31) and Mn intake <1·8 mg (RR 2·00; 95 % CI 1·02, 3·94) were associated with an increased risk of anovulation, compared with higher intakes, respectively. Other measured dietary minerals were not associated with ovulatory function. As essential minerals are mostly obtained via diet, our results comparing insufficient levels with sufficient levels highlight the need for future research on dietary nutrients and their associations with ovulatory cycles.

Associations between daily aspirin use and cancer risk across strata of major cancer risk factors in two large U.S. cohorts

PURPOSE

Daily aspirin use has been shown to reduce risk of colorectal, and possibly other, cancers, but it is unknown if these benefits are consistent across subgroups of people with differing cancer risk factors. We investigated whether age, body mass index (BMI), smoking status, physical inactivity, and family history of cancer modify the effect of daily aspirin use on colorectal, ovarian, breast, endometrial and aggressive prostate cancer risk.

METHODS

We pooled 423,495 individuals from two prospective, U.S.-based studies: the NIH-AARP Diet and Health Study (1995-2011) and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (1993-2009). Using Cox proportional hazards regression, we examined associations between daily aspirin use (≥ 5 days/week) and risk of colorectal, ovarian, breast, endometrial, and aggressive prostate cancer, overall and across strata of risk factors.

RESULTS

Daily aspirin use was associated with a 15% reduction in colorectal cancer risk (hazard ratio [HR]: 0.85, 95% confidence interval [CI] 0.80-0.89). Risk reductions were generally consistent across strata of risk factors but attenuated with increasing BMI (p-interaction = 0.16). For ovarian cancer, there was no significant association overall (HR: 0.93, 95% CI 0.80-1.08) but reduced risk among obese women (HR: 0.73, 95% CI 0.52-0.98, p-interaction = 0.12). Weak or null associations were observed for breast, endometrial, and aggressive prostate cancer, with no strong effect modification observed.

CONCLUSIONS

Daily aspirin use appears to reduce colorectal cancer risk regardless of other risk factors, though the potential modifying effect of BMI warrants further investigation and may need to be considered in risk-benefit calculations for aspirin use.

First-trimester antihistamine exposure and risk of spontaneous abortion or preterm birth

PURPOSE

We tested whether antihistamine exposure during early pregnancy is associated with spontaneous abortion (SAB) or preterm birth (PTB).

METHODS

Women were enrolled in Right from the Start (2004-2010), a prospective pregnancy cohort. Data about first-trimester antihistamine use were obtained from screening and first-trimester interviews. Self-reported outcomes included SAB and PTB and were verified by medical records. Cox proportional hazards models were used to test for an association between antihistamine use and each outcome, both performed adjusting for confounders.

RESULTS

Among the 2685 pregnancies analyzed, 14% (n = 377) reported use of antihistamines. Among antihistamine users, 12% (n = 44) experienced SABs, and 6% (n = 21) had PTBs. Antihistamine exposure was not associated with SAB (adjusted hazard ratio [aHR] = 0.88, 95% confidence interval [CI] 0.64, 1.21) or PTB, which was modified by maternal race (aHR = 1.03, 95%CI 0.61, 1.72 among White women and aHR = 0.43, 95%CI 0.14, 1.34 among Black women).

CONCLUSIONS

Despite the biologic plausibility that antihistamine use may influence pregnancy outcomes, we did not detect evidence of an association with SAB or PTB. These data demonstrate the utility of large prospective cohorts for evaluating drug safety in pregnancy when concerns are raised from animal models.

Serum antioxidant vitamin concentrations and oxidative stress markers associated with symptoms and severity of premenstrual syndrome: a prospective cohort study

Background

It has been suggested that premenstrual syndrome (PMS) may derive from either elevated oxidative stress or reduced antioxidant vitamin levels in the body; however, these relationships have been minimally studied in a large cohort of healthy women. Our objective was to estimate the association between serum concentrations of antioxidant vitamins (A, C, and E) and markers of oxidative stress (F2-isoprostane) with symptoms and severity of PMS.

Methods

The BioCycle study was a prospective cohort study following 259 healthy premenopausal women aged 18–44 years for up to 2 menstrual cycles. Frequency/severity of 20 PMS symptoms were assessed via questionnaires 4 times/cycle, and antioxidant vitamins and oxidative stress biomarkers were measured up to 8 times/cycle to correspond with specific cycle phases. Generalized linear models were used to estimate associations between mean antioxidant concentrations and oxidative stress biomarkers with PMS symptoms and severity; linear mixed models were used to evaluate associations with symptom severity scores within groups (e.g. depression, cravings, pain).

Results

Higher concentrations of serum antioxidant vitamins were largely not associated with prevalence or severity of PMS symptoms. Though a few associations were observed, only associations between mean γ-tocopherol and decreased odds of swelling of the hands/feet survived adjustment for multiple comparisons (OR 0.33, 95% CI 0.16, 0.65, per ug/dL). However, F2-isoprostanes were associated with prevalence and severity of several symptoms specifically related to depression and cravings (depression score β = 0.07, 95% CI 0.02, 0.12, per 10 ug/dL; cravings score β = 0.16, 95% CI 0.10, 0.22, per 10 ug/dL), as well as with classification of PMS severity (OR 1.07, 95% CI 1.01, 1.14, per 10 pg/dL), with these associations surviving adjustment for false discovery rate.

Conclusions

F2-isoprostanes, but not antioxidant vitamins, were associated with select PMS symptoms, as well as symptom and severity categories. Specific symptom relationships merit further research.

Dietary intake of nutrients involved in folate-mediated one-carbon metabolism and risk for endometrial cancer

BACKGROUND

Studies disagree as to whether intakes of folate-mediated one-carbon metabolism nutrients are associated with endometrial cancer.

METHODS

Using data from the large, prospective NIH-AARP Diet and Health Study, we used Cox proportional hazards models to evaluate endometrial cancer risk associated with calorie-adjusted dietary intake of several B vitamins and methionine. All models accounted for age, race, body mass index (BMI), smoking, oral-contraceptive use, menopausal hormone therapy use and caloric intake. We estimated associations by time from baseline (≤3 or >3 years) and stratified models by BMI (<25 or ≥25 kg/m2). During 16 years of follow-up, we identified 2329 endometrial cancer cases among 114 414 participants.

RESULTS

After adjustment for confounding, we observed increased risk for endometrial cancer with greater consumption of dietary total folate, natural folate, B2, B6 and B12 [hazard ratios (HRs) ranging from 1.14 to 1.24 for the highest quintile (Q5) vs the lowest (Q1)]. Higher intakes of total folate, natural folate, B6 and B12 continued to be associated with increased risk when limiting follow-up to >3 years from baseline. We observed risks for the highest intakes of B2 [Q5 vs Q1: HR 1.27 95% confidence interval (CI) 1.07-1.50], B12 (Q5 vs Q1: HR 1.38 CI 1.17-1.63) and methionine (Q5 vs Q1: HR 1.26 CI 1.07-1.48) among women who were overweight/obese, but not among normal/underweight women.

CONCLUSIONS

Our findings indicate that one-carbon metabolism plays a role in endometrial carcinogenesis and exploration of this role in tissue and cellular biology studies is warranted.

Endogenous Progestogens and Colorectal Cancer Risk among Postmenopausal Women

BACKGROUND

The role of progestogens in colorectal cancer development is poorly characterized. To address this, our group developed a highly sensitive assay to measure concentrations of seven markers of endogenous progestogen metabolism among postmenopausal women.

METHODS

The markers were measured in baseline serum collected from postmenopausal women in a case-cohort study within the breast and bone follow-up to the fracture intervention trial (B∼FIT). We followed women not using exogenous hormones at baseline (1992-1993) for up to 12 years: 187 women with incident colorectal cancer diagnosed during follow-up and a subcohort of 495 women selected on strata of age and clinical center. We used adjusted Cox regression models with robust variance to estimate risk for colorectal cancer [hazard ratios (HR), 95% confidence intervals (CI)].

RESULTS

High concentrations of pregnenolone and progesterone were not associated with colorectal cancer [quintile(Q)5 versus Q1: pregnenolone HR, 0.71, 95% CI, 0.40-1.25; progesterone HR, 1.25; 95% CI, 0.71-2.22]. A trend of increasing risk was suggested, but statistically imprecise across quintiles of 17-hydroxypregnenolone (Q2 to Q5 HRs, 0.75-1.44; P _trend, 0.06).

CONCLUSIONS

We used sensitive and reliable assays to measure multiple circulating markers of progestogen metabolism. Progestogens were generally unassociated with colorectal cancer risk in postmenopausal women.

IMPACT

Our findings are consistent with most prior research on circulating endogenous sex hormones, which taken together suggest that sex hormones may not be major drivers of colorectal carcinogenesis in postmenopausal women.

Variability in Sleep Duration and Biomarkers of Cardiovascular Disease Across the Menstrual Cycle

Variability in sleep duration and cardiovascular health have been infrequently investigated, particularly among reproductive-age women. We examined these associations across the menstrual cycle among a cohort of 250 healthy premenopausal women, aged 18-44 years. The BioCycle study (New York, 2005-2007) collected cardiovascular biomarkers (serum high- and low-density lipoprotein (HDL, LDL), total cholesterol, triglycerides, and C-reactive protein (CRP)) at key time points along the menstrual cycle (follicular, ovulatory, and luteal phases). Women also recorded sleep duration in daily diaries. From these data, we computed L-moments, robust versions of location, dispersion, skewness, and kurtosis. We fitted linear mixed models with random intercepts and inverse probability weighting to estimate associations between sleep variability and cardiovascular biomarkers, accounting for demographic, lifestyle, health, and reproductive factors. Sleep dispersion (any deviation from mean duration) was associated with lower mean LDL for nonshift workers and non-White women. Skewed sleep duration was associated with higher mean CRP and lower mean total cholesterol. Sleep durations with extreme short and long bouts (kurtosis) were associated with a lower mean HDL, but not mean CRP, LDL, or triglycerides. Sleep duration modified associations between sleep dispersion and LDL, HDL, and total cholesterol. Even in young and healthy women, sleep duration variability could influence cardiovascular health.

The Relationship between Total Fibroid Burden and First Trimester Bleeding and Pain

BACKGROUND

Few studies comment on the association between fibroids and symptoms among pregnant women. These studies generally are retrospective and do not to assess the influence of number of tumours or their volume on risk of symptoms.

METHODS

Right from the Start is a prospective cohort that enrolled pregnant women from the southeastern USA between 2000 and 2012. In the first trimester, all participants had standardised ultrasounds to determine the presence or absence of fibroids. Symptoms were queried in a telephone survey. We used polytomous logistic regression to model odds of bleeding, pain, or both symptoms in relation to increasing total fibroid number and volume among white and black women.

RESULTS

Among 4509 participants, the prevalence of fibroids was 11%. Among those reporting symptoms (70%), 11% reported only bleeding, 59% reported only pain, and 30% reported both symptoms. After adjusting for age, race, parity, hypertension, smoking, alcohol use, and study site, increasing number of fibroids was associated with pain [odds ratio (OR) 1.16, 95% confidence interval (CI) 1.00, 1.33] and both symptoms [OR 1.25, 95% CI 1.08, 1.45] but not with bleeding among all women. Fibroid volume was not associated with symptoms among black women, but white women with the smallest fibroid volumes were more likely to report both symptoms than those without fibroids [OR 1.79, 95% CI 1.17, 2.72].

CONCLUSIONS

Very large tumours are not requisite for experiencing symptoms, as small fibroids and increasing number of tumours are associated with pain and both symptoms.