Midtrimester intra‐aminotic administration of prostaglandin f 2 α in combination with an hyperosmolar urea solution: Effect upon plasma levels of estradiol, progesterone, and human placental lactogen (hpl)

. A study was undertaken in order to investigate the clinical observation that patients who underwent midtrimester abortion using intra‐amniotic PG F 2α in combination with hyperosmolar urea, always aborted a dead fetus. Ten Caucasian primigravidae, aged between 16 and 22 years and whose pregnancies ranged between 14 and 23 weeks in duration, were studied. The patients were randomly divided into two equal groups. The one group received urea and PG F 2α intra‐amniotically whereas the other received PG F 2α alone. Blood was drawn for measurement of plasma estradiol, progesterone and human placental lactogen (HPL) prior to injection of the abortifa‐cients and at regular intervals thereafter for a period of 120 min. The five patients who received the combination regime of treatment (urea + PG F 2α ) showed a rapid decline in the plasma concentrations of these hormones and induction of abortion was followed by fetal death within 35 min in all cases. In contrast, the five patients who received intra‐amniotic PG F 2α alone, did not (with a single exception), demonstrate this rapid decline in the plasma concentrations of the placental hormones measured. Also with the same single exception, these fetuses, although stillborn, were alive two hours after inducing abortion.