Study Tries Breast Cancer Drug Tamoxifen for Abortion
Yet Another Chemical Abortifacient?

By Randall K. O'Bannon, Ph.D.
NRL Director of Education and Research

Dissatisfied with the lengthy regimen associated with the use of the anti-cancer drug methotrexate to abort, and frustrated by the slow progress of the abortifacient RU 486 through the approval process, abortion researchers are now looking at a new chemical abortion method that employs tamoxifen, a powerful anti-estrogenic compound normally used to fight breast cancer.

Study Results

The University of Southern California study was conducted by noted abortion researchers Daniel R. Mishell, Jr., John K. Jain, and others. It examined the effects of a regimen of tamoxifen used alone or in combination with misoprostol, a powerful prostaglandin that stimulates uterine contractions. One hundred women who were up to eight weeks pregnant were involved. Results were published in the July 1998 issue of the journal Contraception.

According to the report, four women aborted their babies after completing the four-day dose of tamoxifen (20mg once a day for four days). Another 84 women aborted within 24 hours after receiving the prostaglandin misoprostol, the second drug in the regimen. One other woman aborted within three weeks. Another three women aborted their children after being given a second dose of misoprostol.

All told, 92 of the 100 women aborted their babies using tamoxifen or the tamoxifen/misoprostol combination, giving researchers a 92% "success" rate. The pregnancies of six of the remaining eight continuing (later surgically aborted, according to prior agreement). The remaining two women identified as having "incomplete abortions," that is, requiring a surgical procedure to treat (in the words of the study) " excessive or persistent blood loss."

How Tamoxifen Works

The authors do not explain how tamoxifen works other than to point out that tamoxifen is a "selective estrogen receptor modulator" or "estrogen receptor agonist" that had been shown to " interrupt" the pregnancies of pregnant hamsters and guinea pigs in the laboratory.

While progesterone is typically thought of as the "pregnancy hormone," estrogen also plays a significant role in the success of any pregnancy. During pregnancy, estrogen surges help enlarge a woman's breasts and uterus to prepare for the birth and feeding of the child. Estrogen also helps to loosen the ligaments connecting the hips, allowing them to stretch sufficiently to allow the child to pass through the birth canal.

But estrogen is also thought to play a role much earlier on in pregnancy. According to the sixth edition of Guyton's Textbook of Medical Physiology,

There is much reason to believe that estrogens also affect the development of the fetus during pregnancy, for example, by affecting the rate of cell reproduction in the early embryo.

If tamoxifen is an "estrogen receptor agonist," as the study's authors say, tamoxifen would be expected to take over the chemical binding sites which are normally used by estrogen. Estrogen signals the various systems of the body to perform their tasks necessary for the tiny child to thrive, grow, and be born. However, with tamoxifen, rather than estrogen, at the receptor sites, it seems likely that estrogen's "messages" - - to stimulate fetal growth and prepare the uterus - - would not get relayed.1
The estrogen drop off itself would be taken by the body as a signal to begin the menstrual process. The baby would stop growing, and the uterine lining, which functions to feed and protect the child, would break down. The prostaglandin then inserted into the vagina initiates powerful uterine contractions to expel the already dead or dying child.2

Is Tamoxifen Dangerous to Women?

Tamoxifen, in some way, seems to counteract estrogen's stimulation of certain tumors in mammary tissue. It has been used for over 20 years to fight breast cancer. Until recently, the drug was typically used to treat women who had had surgery to remove such tumors, to keep cancers from coming back.

But on the basis of new research, the U.S. Food and Drug Administration (FDA) issued a new recommendation in late October 1998, that women at high risk for breast cancer might take tamoxifen as a preventative measure. The population would include women over 50 with a family history of breast cancer and atypical breast biopsies, who had their first child at age 30 or older and started menstruatingat age 11 or younger.

In making its recommendation, however, the FDA emphasized that tamoxifen should be prescribed only for women in that high-risk category. According to its October 29, 1998, press release,

The agency notes that caution must be used in prescribing the drug because of its potentially serious side effects including endometrial cancer (cancer of the lining of the uterus), deep vein thrombosis (blood clots in major veins), and pulmonary embolism (serious blood clots in the lungs).

Indeed, information from the web site of the National Cancer Institute (NCI) indicates that women taking tamoxifen had twice the chance of developing uterine cancer as women taking placebos. The NCI notes that "breast cancer patients who developed uterine cancer while taking tamoxifen have died from the disease."

The institute also mentions other studies and reports linking tamoxifen to depression, eye problems, and cancers of the liver and digestive tract. However, it does not, at this point, present these results as conclusive.

Because of estrogen's wide range of effects over the body, it is not surprising that women taking tamoxifen might encounter these sort of side effects. Commenting on the risks associated with tamoxifen, then-acting FDA Commissioner Michael Friedman was quoted in the FDA's press release issuing the following warning:

As with all drugs, there are risks associated with use. As valuable as tamoxifen is to some patients, FDA strongly advises women and their doctors to carefully weigh the benefits and risks of tamoxifen before patients use the drug.

For women facing the serious likelihood of a potentially fatal breast cancer, the benefit may well outweigh the risk. But one is hard pressed to explain why a reputable doctor would ever suggest that a woman not facing a heightened risk of a deadlydisease take such a dangerous drug.

In explaining their reasons for experimenting with tamoxifen, Drs. Jain and Mishell are quite straightforward in mentioning (1) the delays in the approval process for RU 486 and (2) dissatisfaction with the other cancer drug, methotrexate, now being studied for abortion in several Planned Parenthood locations around the country.

In both their introduction and final discussion, Jain and Mishell note that RU 486 is currently unavailable in the U.S. and say it is "uncertain" when this drug will become available for general use as an abortifacient in the U.S.

Jain and Mishell draw attention to the fact that only about 65% of the abortions done using the anti-cancer drug methotrexate occurred within a day following the first or second administration of the prostaglandin used in the second stage to expel the body of the dead baby. The remaining women aborted only after a mean delay of 24 days after the dose of the prostaglandin. Jain and Mishell further noted thatuterine bleeding for the methotrexate method generally lasted 11 to 14 days.

They undertook the tamoxifen study, Jain and Mishell write, "in an effort to develop a medical [their term for chemical abortions] method of abortion with a rate of effectiveness and short duration of action similar to that of the mifepristone [RU 486] plus prostaglandin combination," using a "currently available" drug, tamoxifen, believed to have abortifacient properties.

RU 486, developed in France in the early 1980s and used for abortions there for over a decade, still is not available on the U.S. market, owing to difficulties the sponsor has had in finding a manufacturer. A recent article in Mother Jones magazine (Jan./ Feb., 1999) reports that the sponsor now has manufacturers for the drug, but provides no names nor offers a firm release date.

While impatiently waiting for RU 486 to gain final government approval, many abortion researchers turned to methotrexate, a powerful anti-cancer drug used since the 1950s to fight certain fast-growing tumors and known to have abortion-inducing side effects. While "successful" about 96% of the time in inducing abortion, methotrexate has proven less attractive to many abortionists and their clients because it tends to take longer to work than RU 486. Also, some abortionists have not wanted anything to do with methotrexate owing to its high toxicity.

And so the quest for the "perfect" abortifacient continues. Tamoxifen is one of the latest, but may not be the last attempt. Another article appearing in a later issue of Contraception (the journal that published Jain and Mishell's research) studied the abortifacient effect of castor bean extract in pregnant rabbits. (The rabbit fetuses were aborted, but side effects for mothers led researchers to recommend against its use.) More studies with other drugs are sure to follow.

The abortion industry knows that women do not like conventional surgical abortions. Women use words like "mechanical," "invasive," and "impersonal" to describe their abortion experiences. They don't like the "scraping" and fear, quite rightly, that it may lead to injury or infertility.

Business in the abortion industry has declined, with nearly 250,000 fewer abortions and almost a thousand fewer abortionists in 1996 than there were just over five years before. A lack of respect from their medical peers and increasing discomfort with the procedure has precipitated many an abortionist to leave the business.

Moreover, public support for abortion has declined in recent years, with more people now recognizing abortion as the taking of human life.Into this set of circumstances steps the abortion industry with promises of new and easy abortions by pill, abortions that involve no surgery, abortions that can be done "quickly" and " painlessly" in the privacy of a woman's own home.

The problem is that none of the methods has proven to be easy, safe, or simple. They involve several drugs and multiple doctor visits over a period of several days or weeks.

Far from being painless, these chemical abortions typically involve a great deal of pain, in addition to vomiting, diarrhea, and other nasty side effects. More toxic long-term side effects of these drugs, such as those mentioned above, are usually ignored or unexamined in the frenzied effort to get these drugs into general circulation.

Most significantly, for all the new packaging, nothing changes the fact that the point or purpose of these new chemical methods is still what it was before with the surgical methods of abortion - - the death of an unborn child. And there is nothing the industry can ultimately do to make that an attractive or acceptable option.

FOOTNOTES:

1 Others, citing more recent research, have identified tamoxifen as an estrogen antagonist, that is, a chemical which directly interferes with estrogen itself. In either case, the result would be the same in that the important estrogen signal does not get relayed.

2 Studies have shown that the prostaglandin misoprostol, used alone, can often induce abortion. This leads to speculation that it is the prostaglandin, rather than the drugs, doing the real abortive work.