UC Researchers Begin Testing of RU 486 Pill : Medicine: Study on French ‘morning-after’ pill is part of an international effort to determine the minimum dose for preventing pregnancy. Anti-abortionists denounce the decision.
Researchers at UC San Francisco announced Tuesday that for the first time in the United States they will begin testing RU 486--the controversial French abortion pill--as an emergency contraceptive for women who have had unprotected sex and do not want to get pregnant.
The study, which is generating protests from anti-abortion activists, is part of an international effort designed to determine the best dose for the so-called “morning-after pill,” which works by blocking progesterone, a key hormone to maintaining pregnancy.
If it is successful, the study--which is being conducted with the approval of the U.S. Food and Drug Administration--could help persuade government officials to legalize RU 486 in the United States.
“This marks a new era of contraceptive research for American women,” said Dr. David Grimes, the UC San Francisco professor of obstetrics and gynecology who is heading the study. “We think it is also very important that we are working in this exciting area of anti-progestines. We have just begun to explore this compound.”
Now, only France, Sweden, China and the United Kingdom permit public distribution of RU 486. However, the pill has been tested in the United States for a variety of uses. In November, doctors at Long Beach Memorial Hospital began a study of RU 486 as an alternative to chemotherapy for women with advanced breast cancer. Researchers at UC San Diego have also tested the pill as a treatment for women with fibroid tumors, benign tumors of the uterus, and endometriosis, in which fragments of the uterine lining are found in the pelvic cavity, commonly causing infertility.
RU 486 will also be tested in Oregon as an abortion pill. But Grimes drew a distinction between that study and his, in which women will be given the drug as an emergency contraceptive within five days after having unprotected sex.
He said previous studies in the United Kingdom have shown that a 600-milligram dose of RU 486--taken in three pills--can prevent pregnancy, but that researchers suspect a much lower dose would be as effective. The aim of the San Francisco study is to establish the minimum dose; study participants who get pregnant in spite of the drug will be offered abortions at no cost, he said.
According to Grimes, the pill works by preventing a fertilized embryo from implanting into the uterus. He said most medical experts agree that pregnancy begins not at fertilization, but about two weeks later, after the embryo has traveled from the Fallopian tubes and attached to the uterine lining.
But at the National Right-to-Life Committee in Washington, spokesman Richard Glascow told the Associated Press that calling RU 486 a contraceptive is a misnomer. “The proposed testing of RU 486 as a contraceptive is fundamentally misleading because it works not to prevent conception but to cause abortion,” he said.
Grimes countered: “Abortion is interruption of an established pregnancy. In this case we’re preventing a pregnancy from occurring.” He said the views of anti-abortionists are “just rhetoric. It suggests that they don’t understand the biology involved.”
The study, which is sponsored by the World Health Organization, will include a total of 2,100 women at 14 sites worldwide. UC San Francisco is the only U.S. testing center in the program. Grimes said he hopes to enroll 150 Bay Area women. He is urging women who want emergency contraception to call San Francisco General Hospital, where the study is taking place.
The research got under way as soon as the study was announced Tuesday. Within five hours, Grimes said, he had received several dozen telephone calls from women wanting to participate. Those women will be screened and, if they are eligible, given the drug as soon as possible, he said.
Grimes said there already is a method of emergency contraception available to women--although most have never heard of it. The so-called Yuzpe regimen, named after a Canadian researcher, calls for women to take two birth control pills immediately after having unprotected sex, followed by another two pills 12 hours later.
But Grimes said there are drawbacks to that method: Taking that many birth control pills in one day can cause nausea and vomiting, and it is not as effective as the 600-milligram dose of RU 486. However, the women who participated in the earlier RU 486 research sometimes experienced up to a two-week delay in their next menstrual period, he said.
