Longer delay before prostaglandin administration improves effectiveness of medical abortion regimen

Family Planning Perspectives, Jan/Feb 1996 by Althaus, F

Methotrexate and vaginal misoprostol constitute a safe and highly effective regimen for medical abortion, according to two recent studies in New York and San Francisco. In the New York study, which included 178 women, 96% of patients aborted without need for a surgical procedure.l The San Francisco study, in which 88% of patients had a successful medical abortion, found that the drug regimen was more effective when the misoprostol was given seven days rather than three days after the methotrexate.2 Complete abortion occurred in 83% of the group with the threeday delay, compared with 98% of the group with the seven-day delay

The New York Study

Women who requested medical abortion were eligible for the study if they had been pregnant for no more than 63 days, had no medical contraindications and were capable of providing informed consent. After supplying a medical history and receiving a thorough physical, including a complete blood count and a vaginal ultrasound examination, the women were given an injection of methotrexate at a dose of 50 mg per square meter of body surface area. Five to seven days later, 800 mcg of misoprostol was administered vaginally, in tablet or suppository form. Each woman was given a prescription for acetaminophen with codeine.

Seven days after administration of the misoprostol, each woman received a pelvic examination and an ultrasound examination. If the ultrasound examination indicated an incomplete abortion, the clinicians performed vacuum aspiration; if it showed a gestational sac, they offered the woman a choice between vacuum aspiration and a second dose of misoprostol.

Of the 178 women in the study, 171 (96%) had a successful abortion (defined as the complete termination of pregnancy within seven days after the first or second administration of misoprostol), 153 after the first dose and 18 after the second. Overall, 88% aborted within 24 hours after the first or second dose of misoprostol. Seven women required suction curettage; examination of the tissue indicated that none of these pregnancies were still viable.

For the majority of women (84%), heavy bleeding lasted no more than a day after medical abortion, with 14% reporting a duration of 2-4 days and 2%, 4-7 days. Overall, 74% of the women said they experienced little or moderate pain; only three required more medication than originally prescribed. Nine women reported transient diarrhea, and six reported nausea greater than what they had experienced during the pregnancy

The investigators note that unlike regimens using mifepristone and misoprostol, the methotrexate-misoprostol regimen does not require women to remain at the doctor's office or clinic for an extended period of time after vaginal administration of misoprostol. They conclude that "medical termination of pregnancy with methotrexate and intravaginal misoprostol is effective, safe, and easily implemented in a clinical practice."

The San Francisco Study

The study included 88 women who were 18 years of age or older and seeking an abortion. Participation was limited to women pregnant for 56 days or less. (Gestational age was calculated from the first day of the woman's last menstrual period unless the ultrasound estimate differed by four days or more.) Participants had to have access to a telephone, be willing to abstain from intercourse and alcohol for the first 14 days of the trial, and agree to comply with the visit schedule and to have a surgical abortion if they had an ongoing pregnancy 14 days after the beginning of treatment. Women were excluded if they used any medication that might interfere with the treatment or if they had any physical condition that might raise the risk of complications.

After providing a medical history and receiving a complete physical examination-including a baseline blood cell count, a gonorrhea culture and a pregnancy test measuring serum human chorionic gonadotropin levels-all participants were given an injection of methotrexate at a dose of 50 mg per square meter of body surface area. Clinicians then randomly assigned the women to one of two return-visit schedules. One group returned on the fourth, eighth and 14th days of the study, while the other returned on the eighth, ninth and 14th days. Neither patients nor clinicians were blinded to treatment-group assignments.

On her first return visit, each woman had a vaginal ultrasound examination and received 800 mcg of misoprostol administered vaginally All patients were given a small supply of ibuprofen and a prescription for acetaminophen with codeine. On a woman's second return visit, the clinicians repeated the ultrasound examination. If the gestational sac was no longer present, no further ultrasound examinations were performed; if the ultrasound revealed an ongoing pregnancy, a second dose of misoprostol was administered.

On the third return visit (day 14), the clinicians performed complete blood cell and platelet counts for all patients and ultrasound examinations as needed. All women whose ultrasound at the second or third visit showed no gestational sac were instructed to return in four weeks for a urine pregnancy test.