25-Hydroxyvitamin D and Long Menstrual Cycles in a Prospective Cohort Study.

ABSTRACT:

Background

Vitamin D insufficiency is associated with subfertility and prolonged estrus cycles in animals, but humans have not been well studied.

Methods

A 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.

Results

There were 1,278 menstrual cycles from

SUBMITTER: Jukic AMZ 

PROVIDER: S-EPMC5882585 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature