ArticleEpidemiology (Cambridge, Mass.)2018
25-Hydroxyvitamin D and Long Menstrual Cycles in a Prospective Cohort Study.
Article in Epidemiology (Cambridge, Mass.), 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers.
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Who cites it
31 citing papers in PubMed.
- Vitamin D Status and Reproductive Hormonal Profiles in Early Versus Physiological Menopause: A Comparative Observational Study.Biomedicines · 2026Article
- Associations between self-reported personal care products use and menstrual cycle length and regularity in a US digital cohort.Environment international · 2026Article
- An Overview of the Impact of the Menstrual Cycle on Nutrient Metabolism: An Integrative Perspective.Nutrients · 2026Review
- The Investigation of Vitamin D and Menstrual Cycles Trial (the inVitD Trial): A clinical trial of vitamin D supplementation on the hypothalamic-pituitary-ovarian axis.Contemporary clinical trials · 2026Article
- Vitamin D status in North American managed black rhinoceros (Conservation physiology · 2026Article
- Impact of vitamin D deficiency on defective endometrial decidualization and the repressive role of vitamin D receptor (VDR) in the epigenomic network.bioRxiv : the preprint server for biology · 2025Article
- Ambient air pollution in critical windows of exposure and spontaneous miscarriage in a preconception cohort.Environmental research · 2025Article
- The Menstrual Cycle as a Vital Sign: a comprehensive review.F&S reviews · 2025Article
- Article
- Dietary and Lifestyle Management of Functional Hypothalamic Amenorrhea: A Comprehensive Review.Nutrients · 2024Review
- Association between serum 25-hydroxyvitamin D and antimüllerian hormone levels in a cohort of African-American women.Fertility and sterility · 2024Article
- Vitamin D status and supplementation, calcium supplementation, and timing of natural menopause.Maturitas · 2024Article
- Seasonal variations of menstrual cycle length in a large, US-based, digital cohort.International journal of hygiene and environmental health · 2024Article
- Vitamin D and Toxic Metals in Pregnancy - a Biological Perspective.Current epidemiology reports · 2024Review
- Vitamin D status during pregnancy: a role in intergenerational reproductive health?European journal of epidemiology · 2023Article
- Systemic inflammation and menstrual cycle length in a prospective cohort study.American journal of obstetrics and gynecology · 2023Article
- Review
- Vitamin D and uterine fibroid growth, incidence, and loss: a prospective ultrasound study.Fertility and sterility · 2022Article
- Covid-19 vaccination and menstrual cycle length in the Apple Women's Health Study.NPJ digital medicine · 2022Article
- Preconception vitamin D and miscarriage in a prospective cohort study.Human reproduction (Oxford, England) · 2022Article
Corrections and comments
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Authors and funding
5 authors.
Funding
Abstract
backgroundVitamin D insufficiency is associated with subfertility and prolonged estrus cycles in animals, but humans have not been well studied.
methodsA prospective time-to-pregnancy study, Time to Conceive (2010-2015), collected up to 4 months of daily diary data. Participants were healthy, late reproductive-aged women in North Carolina who were attempting pregnancy. We examined menstrual cycle length as a continuous variable and in categories: long (35+ days) and short (≤25 days). Follicular phase length and luteal phase length were categorized as long (18+ days) or short (≤10 days). We estimated associations between those lengths and serum 25-hydroxyvitamin D (25[OH]D) using linear mixed models and marginal models.
resultsThere were 1,278 menstrual cycles from 446 women of whom 5% were vitamin D deficient (25[OH]D, <20 ng/ml), 69% were between 20 and 39 ng/ml, and 26% were 40 ng/ml or higher. There was a dose-response association between vitamin D levels and cycle length. Compared with the highest 25(OH)D level (≥40 ng/ml), 25(OH)D deficiency was associated with almost three times the odds of long cycles (adjusted odds ratio [aOR] = 2.8 [95% confidence interval (CI) = 1.0, 7.5]). The aOR was 1.9 (1.1, 3.5) for 20 to <30 ng/ml. The probability of a long follicular phase and the probability of a short luteal phase both increased with decreasing 25(OH)D.
conclusionsLower levels of 25(OH)D are associated with longer follicular phase and an overall longer menstrual cycle. Our results are consistent with other evidence supporting vitamin D's role in the reproductive axis, which may have broader implications for reproductive success.
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