Abortifacient Brief: The Birth Control Pill

Brian Clowes
Reproduced with Permission
Human Life International

What exactly is abortifacient birth control? Essentially, it's a contraceptive that actually can cause early abortion. The majority of women who want to inhibit their fertility (as of 2012, about 10.7 million Americans[1]) turn to such methods. The principal method of abortifacient birth control is "the Pill," which first became widely used in the late 1960's and helped fuel the Sexual Revolution.

Here are 5 things you should know about birth control pills.

#1. The Pill can cause abortion.

The term "contraceptive" indicates that the results prevent a woman from being fertile at all. However, all birth control pills on the market today function as abortifacients part of the time. The Pill ends early pregnancies part of the time by preventing implantation of an already fertilized egg.

How does this happen?

Over the past half-century, three general classes of birth control pill have been manufactured in the United States and other countries - the high‑dose pill, the low‑dose pill and the progestin-only "mini‑pill."

Users of the old high‑dosage birth control pills experienced relatively severe side effects. These pills were considered non‑abortifacient in their two‑fold modes of action. The pills generally worked by thickening cervical mucus and inhibiting ovulation, but not by preventing implantation of a developing human being in the uterine lining. Sometimes, however, breakthrough ovulation occurred, and so the older pills were only occasionally abortifacient in their actions.

The newer low‑dosage pills have three modes of action:

There are now more than 120 brands and varieties of birth control pills on the market. All of them - from Alesse to Zovia - sometimes prevent implantation of the developing human being impossible. This means that all of the newer oral contraceptive pills act as abortifacients at least part of the time.

#2. The high-dose pill has serious side effects.

The Searle Pharmaceutical Corporation developed the first birth control pill, Enovid, in the late 1950s.

Enovid and other high‑dose pills, which have generally fallen out of favor in the United States but are still used in some developing countries, contain from 1 to 12 milligrams of progestin and/or 60 to 120 micrograms of estrogen, a natural female hormone. This high dosage had a variety of side effects, including blurred vision, nausea, weight gain, breast pain, cramping, irregular menstrual bleeding, headaches, and possibly breast cancer.[2]

Beginning in about 1975, pill makers, reacting to extensive publicity about the severe side effects of the high‑dosage pills, steadily decreased the content of estrogen and progestin in their products.

#3. Pharmaceutical companies use the poor to test abortifacient birth control.

In keeping with its defensive anti‑lawsuit strategy, Searle tested the Pill on poor Puerto Rican women before concluding in 1961 that it was safe for women on the American mainland to use.[2]

Experimentation on foreign women is a typical tactic of the major pharmaceutical companies. They often test abortifacient birth control chemicals and devices on poor women in developing countries so any mistakes or serious health problems are easier to cover up. Poor women in these nations have little recourse when their health is destroyed or damaged by this kind of testing, because the investments of large pharmaceutical companies brings huge amounts of money to their homelands, and any protest against the testing programs can easily be suppressed by local or national governments.

#4. The high-dose pill was replaced by a pill that causes frequent abortion.

Eventually the older "high‑dose" pills gave way to the new "low‑dose" pills. Ortho/Johnson& Johnson, G.D. Searle/Monsanto, and Syntex, the three largest manufacturers of abortifacient birth control pills in the United States, voluntarily withdrew their "high‑dose" products from the U.S. market in 1988 on the advice of the U.S. Food and Drug Administration (FDA). These were among the last commercially‑available pills in the United States containing more than 50 micrograms of estrogen.[2]

Each of the newer low‑dose pills contain from 0.05 to 3.0 milligrams of a variety of compounds containing progestin and from 0.01 to 0.05 milligrams of estrogen in the form of ethinyl estradiol or mestranol, a tremendous drop in estrogenic potency compared to the high‑dose pills.[3]

The low‑dose pills work in essentially the same manner as the high‑dose pill. However, a much higher percentage of ovulation occurs in women who use the low‑dose pills due to their lower estrogen dose. This means that women who use these pills frequently conceive. In order to prevent pregnancies in these cases, the low‑dose pills also prevent implantation, thereby acting as back-up abortifacients. Several studies have shown that women on the low-dose birth control pills experience an early "silent abortion" during 5–13% of their cycles.

#5. The mini‑pill is usually an abortifacient.

Scientists have not pinpointed the primary mechanism of action of mini‑pills (progestin‑only pills). However, women who use them frequently ovulate.

It is known that pills that contain only progestin alter the cervical mucus. They interfere with implantation by affecting the endometrium (lining of the uterus) and suppressing ovulation in some women by reducing the presence of follicle‑stimulating hormone (FSH).

This mechanism is confirmed by the Food and Drug Administration, which has stated that "Progestin‑only contraceptives are known to alter the cervical mucus, exert a progestinal effect on the endometrium, interfere with implantation, and, in some patients, suppress ovulation."[4] This is not a new finding: the Department of Health and Human Services (HHS), in its 1984 pamphlet "Facts about Oral Contraceptives," compared the performance of high‑dose pills to mini‑pills:

It is possible for women using combined pills (synthetic estrogen and progestin) to ovulate. Then other mechanisms work to prevent pregnancy. Both kinds of pills make the cervical mucus thick and "inhospitable" to sperm, discouraging any entry to the uterus. In addition, they make it difficult for a fertilized egg to implant, by causing changes in Fallopian tube contractions and in the uterine lining. These actions explain why the minipill works, as it generally does not suppress ovulation [emphasis added].

The manufacturers of the mini‑pills acknowledge this mode of action. For example, Syntex Laboratories announced that its progestin‑only pill Norinyl "did not interfere with ovulation….It seems to affect the endometrium so that a fertilized egg cannot be implanted."[5]


The Pill is not conception control. Though that may have been the original intention, the developments of medicine have led to the creation of contraceptives which also act as abortifacients in cases where conception is not prevented.

Hence, oral contraceptives are not true contraceptives but abortifacient birth control.