Physiologic Mechanisms Underlying Ovarian Follicular Waves During the Menstrual Cycle

Physiologic Mechanisms Underlying Ovarian Follicular Waves During the Menstrual Cycle

The research aims to characterize changes in ovarian and pituitary hormones associated with the development of ovarian follicular waves during the human menstrual cycle.

Our laboratory's previous research has demonstrated that multiple waves of ovarian follicles develop throughout the menstrual cycle. Approximately 2/3 of women develop 2 follicle waves throughout their cycle while the remainder exhibit 3 waves of follicle growth (1,2). This study is to follow up on those findings to determine how pituitary and ovarian hormones regulate the development of follicle waves in women, with a combination of ultrasound scans and blood and urine sampling to characterize how follicles grow during the menstrual cycle in 50 women of reproductive age. Changes in follicle growth across the cycle will be compared with changes in hormone production.

The new findings will be essential for improving understanding of female reproduction, with clinical applications in contraception, fertility and menopausal care for women across their reproductive lifespan.

Inclusion Criteria:

• Healthy biological females
• Regular menstrual cycles (21-35 days)

Exclusion Criteria:

• BMI <18 or >30
• Pregnancy
• Breastfeeding mothers
• Current infertility
• History of hysterectomy or oophorectomy
• Reproductive health issues that can interfere with study outcomes
• Smoking
• Metabolic syndrome (blood pressure, fasting glucose, fasting insulin and serum lipids measured to assess eligibility)
• Not on any hormonal medication that affects reproduction (including hormonal contraception)
• Hyperprolactinemia
• Abnormal thyroid stimulating hormone assay