Aim To assess whether regular administration of pethidine during medical termination of pregnancy in the second trimester leads to faster completion of the procedure.

Methods 54 patients admitted for a second trimester termination of a singleton pregnancy were included. Gestational age ranged from 13⁺¹ to 23⁺⁶. Exclusion criteria were: threatened spontaneous abortion or dilatation of the cervix, use of additional oxytocics, allergy to misoprostol or pethidine and need to complete the procedure surgically. The history was obtained including previous pregnancies and details of previous instrumentation of the cervix. The patient was assessed clinically and an obstetric ultrasound was performed. The procedure started with a dose of 400mcg of misoprostol orally and 400mcg per vaginum. The vaginal dose was repeated 6-hourly. 9 h after the first dose of misoprostol, 50mg of pethidine were given intramuscularly. The same dose was repeated every 6 h. The time of the expulsion of the fetus and its weight were noted. The duration of the procedure was compared with a retrospective group of 49 patients, who had the procedure with the use of misoprostol alone.

Results Regular administration of pethidine does not appear to facilitate the evacuation of the uterus in medical termination of pregnancy in the second trimester. Factors associated with faster completion of the procedure were: previous vaginal birth, history of more than 2 surgical evacuations of the uterus and fetal weight less than 450 g.