Michels KA, et al. – This study was performed to assess the relationship between folate, homocysteine and the ovarian cycle among healthy regularly menstruating women. It was concluded that the higher homocysteine was related to 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.

Methods

• For this research, they designed a prospective, longitudinal cohort (The BioCycle Study).
• Between 2005–2007, total 259 regularly menstruating women not using hormonal contraceptives or dietary supplements who were followed for up to two menstrual cycles were enrolled in this study.
• Serum folate and reproductive hormones were measured up to eight times per cycle and plasma homocysteine up to three times.
• Linear mixed models were utilized to estimate the relationship 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 utilized to analyze the risk of sporadic anovulation.
• All models were adjusted for age, race, body mass index, cigarette and alcohol use, and energy and fiber consumption.

Results

• Higher plasma homocysteine concentrations were related to 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 related to 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 related to a 33% increased risk of sporadic anovulation.
• They found no risk related to reduced folate concentrations, but a higher ratio of folate to homocysteine at ovulation was related to a 10% reduced risk of anovulation.