Vaginal progesterone after tubal pregnancy.

We studied the effect of vaginal progesterone (P) treatment during the luteal phase of patients who had had a tubal pregnancy (TP) and were planning another, in a prospective, randomized, double-blind trial. The outpatient clinics of two University hospitals and three central hospitals had 135 patients treated for tubal pregnancy: 100 with grossly normal fallopian tubes (supposing an accidentally abnormal luteal phase as a possible etiology of their first TP) and 35 with signs of earlier pelvic inflammatory disease (PID etiology). They were treated with vaginal P (25 mg b.i.d.) or placebo during cycle days 16-24, for 10 months. Serum P levels after a single vaginal or oral dose were compared. The rates of conception, delivery, spontaneous abortion and recurrent TP were recorded, and fetal and placental weight measured. Both vaginal and oral formulas of P provoked a physiological (24-43 nmol/l) rise in serum concentrations. P and placebo-treated cycles resulted in a nearly equal number of pregnancies (33/37 resp.). Of the 55 infants born 53 were to mothers without signs of earlier PID (53/100); only 2 (2/35) to mothers in whom signs had been present. Recurrent TP occurred in 9% of all pregnancies. Four out of six recurrent TPs were patients with signs of PID (4/35), but two were without such signs (2/100): one occurred during placebo and one during P-treated cycle. Prophylactic P treatment of patients at risk of recurrent TP does not improve fertility or prevent recurrent TP. This indicates, that the functional etiology of recurrent TP, as compared to infection, is not important.

Progesterone support of the luteal phase in in vitro fertilization program--a hazard?

To study the effect of progesterone support of the luteal phase in a stimulated cycle a subgroup of our IVF patients was treated with progesterone vaginal suppositoria. The treatment was initiated on the aspiration day. There was no significant difference in the pregnancy or abortion rate between the control group and the gestagen therapy group. However, it seems that progesterone support may increase the pregnancy rate but also the rate of spontaneous abortion. This suggests that the effective and early started progesterone supplementation of the luteal phase may cause the implantation of abnormal nonviable embryos.

Effect of intravenous infusion of betasympathomimetic agents on plasma renin activity during pregnancy.

The plasma renin activity (PRA) was measured in 26 pregnant patients before and during ritodrine infusion (10 patients), during isoxsuprine infusion (12 patients), and during glucose infusion (4 control patients). All patients were in the third trimester of pregnancy, not in labour and not hypertensive. A low dose of ritodrine, a beta2 adrenergic agent, caused a rise of PRA but no simultaneous rise in heart rate; this suggests that beta2 activity is involved in renin release. Normal doses of ritodrine and isoxsuprine increased the maternal heart rate to 110 to 120 beats/minute and also doubled the PRA level. Two hours after the end of the ritodrine infusion the PRA level was still above that before the infusion. The results suggest high reserves of renin during pregnancy.