Relationship between sleep and secretion of gonadotropin and ovarian hormones in women with normal cycles

Objective: To monitor gonadotropin and ovarian hormone levels in relation to sleep duration in normally cycling women. Design: Observational and cross-sectional study. Setting: Multicentric collaborative study. Patient(s): One hundred six healthy and normally cycling women, aged 19 to 44 years, with cycle lengths of 24 to 34 days. Intervention(s): Follow-up during one to four consecutive cycles with daily urine collection. Main Outcome Measure(s): Urine concentrations of LH, FSH, estrone-3-glucuronide (E1-3-G), and pregnanediol-3-alpha-glucuronide (Pd-3alpha-G). Ultrasound determination of day of ovulation and estimation of sleep duration. Result(s): We found a significant association between FSH levels and sleep duration (P = .008). Follicle-stimulating hormone levels were 20% higher in long-time sleepers than in short-time sleepers. This association persisted whatever the age or the body mass index. There was no significant association between belonging to any group and LH, E1-3-G, or Pd-3a-G levels. Conclusion(s): Our results suggest that sleep duration could be related to FSH levels, although the study design did not allow us to establish a causal relationship nor to explain the physiological basis of the observed relationship.