The pattern of serum levels of pregnancy-associated plasma protein A (PAPP-A) during the ovulatory menstrual cycle.

Pregnancy-associated plasma protein A (PAPP-A) was measured throughout the menstrual cycle in eight women at daily intervals. The protein could be detected in all serum samples, and one patient showed consistently high PAPP-A values during the entire observation period. Twenty-six more women were tested by measuring a single serum specimen. No further high PAPP-A levels were discovered in these. There is no significant difference in PAPP-A concentration between the follicular and the luteal phase of the cycle.