Luteal phase progesterone excretion in ovulatory women with polycystic ovaries.

BACKGROUND: Various studies have reported a prevalence of polycystic ovaries (PCO) of approximately 20% in the 'normal' population. Our aim was to investigate the frequency of ovulation and pattern of luteal phase progesterone secretion in a group of women with PCO who reported regular cycles and in whom ovulation had been established on the basis of previous investigations.
METHODS: Subjects collected early morning urine samples for pregnanediol-3-glucuronide measurement from day 10 of the cycle to day 1 of their next menses. Results in three consecutive cycles from women with PCO (group 1, n = 10 and 29 for patients and cycles respectively) were compared with results from two groups with normal ovaries; with either infertility (group 2, n = 10 and 30) or proven fertility (group 3, n = 6 and 19).
RESULTS: There were considerable variations in cycle length. The median (range) was group 1: 28 (23-47); group 2: 26 (21-36) and group 3: 27 (25-38) days with more short cycles in both infertile groups. There was more variation in pregnanediol:creatinine in the normal-ovary infertile and PCO groups than in the fertile controls. Levels were higher in the early luteal phase in the fertile normal group than in either infertile group, and the mid-luteal phase peak was lower in the infertile women with normal ovaries. In summary, there was greater variability in luteal phase pregnanediol:creatinine ratios in the PCO and infertile normal-ovary groups than in women with normal ovaries and proven fertility.
CONCLUSION: Women with PCO did not have more variation in cycle length than fertile women with normal ovaries, but there were significantly lower levels of progesterone in the early luteal phase. This may contribute to the delay in conception in these patients.