Decrease in human plasma gravidin levels after medical abortion.

The aim of this study was to determine if loss of pregnancy is associated with a decrease in plasma levels of gravidin, a phospholipase inhibitor thought to maintain pregnancy. Blood was taken from 28 women in the first trimester of pregnancy who had requested an abortion. The progesterone receptor antagonist, RU-486 was given on Day 0 for termination of pregnancy. Plasma gravidin levels were measured on day 0 and on day 2 just before the patients were given misoprostol, a prostaglandin E1 analogue (600 micrograms). In a small group of patients, plasma measurements were continued up to 42 days. By day 2, plasma gravidin levels had fallen significantly (100% to 94%, p = 0.010 in a paired t-test). Following treatment with prostaglandins and pregnancy loss, plasma gravidin levels continued to fall until day 14 when the non pregnant level was reached at 80% of the pregnant level. We conclude that a decrease in plasma gravidin levels is associated with loss of pregnancy. This may occur because progesterone action is blocked.