LOW LUTEAL-PHASE SERUM PROGESTERONE LEVELS IN REGULARLY CYCLING WOMENARE PREDICTIVE OF SUBTLE OVULATION DISORDERS

Serial hormonal and ultrasound measurements were performed in a group of 50 infertile women with regular menstrual cycles of normal length, and evidence of luteinization by measurement of biphasic basal body te mperature (BBT). The progesterone levels however, remained below a cri tical threshold of 32 nmol/l (1 nmol/l = 0.315 ng/ml) in two cycles. I n 50 cycles, 25 showed definite abnormalities. In 16 other cycles, ovu lation was observed, but relatively low luteal progesterone followed. Although pregnancy in these 16 cycles could be less likely, the real s ignificance of this finding is questionable. The etiology of these 'su btle cycle anomalies' is not clear and may be multifactorial. For this reason, no therapy other than use of ovulation-inducing agents by tri al and error is as yet available. Preliminary results indicate that cy cle disturbances may persist under ovulation induction, even though pr ogesterone levels are normalized.