Do Oral Contraceptives Cause Abortions?

The purpose of this article is to point out that there is disagreement among sincere pro-life physicians, including members of the APP, over the answer to this question. First, we will present a precise definition of terms, critical to prevent equivocation and to contribute to your understanding of the debate. Second, we will present a brief description of the proposed methods of action of oral contraceptives (OCs). Third, we will present the argument that oral contraceptives are abortifacient, and therefore, unconscionable, and ethical physicians should not prescribe them. Fourth, we will present the argument that they are not abortifacient and that physicians who are against abortion may prescribe them without a strain of conscience. We present the best arguments we can for both of these opposing positions. Lastly, we will briefly examine the so-called progestin-only pill or “Minipill”, the IUD (intra-uterine device), and the morning-after pill or “emergency contraception”, each of which are clearly abortifacient.

First, some basic definitions:

Conception, or fertilization: occurs when a sperm fertilizes an oocyte. Conception normally occurs in the fallopian tubes. Conception marks the first stage of human existence, when a unique human being comes into existence. (For more thorough arguments proving that life begins at fertilization, see the APP article, “When Does Life Begin?”)

Implantation: occurs when the new living human being implants into the inner lining of the uterus, or the endometrium. This occurs about one week after conception.

Intentional abortion: occurs when the new human being is intentionally killed, for therapeutic or elective reasons, through chemical or surgical means.

Unintentional abortion: occurs when the new human being is unintentionally aborted, or miscarried. The mother may or may not be aware that this occurs, because the aborted baby may pass out of her with her menses.

Miscarriage: accidental fetal loss through natural means; referred to in the medical literature as a “spontaneous abortion”.

Contraceptive: a drug that prevents conception, and therefore prevents the formation of a new human being.

Abortifacient: a drug that kills a newly formed human being, whether by directly killing the baby or by preventing implantation, and so cause an abortion, either intentionally or unintentionally.

Let us briefly review what the medical literature claims are the three methods of action of OCs.

1. Primarily, they inhibit ovulation by suppression of the pituitary/ovarian axis.

2. Secondarily, they inhibit transport of sperm through the cervix by thickening the cervical mucus.

3. They cause changes in the endometrium that have historically been assumed to decrease the possibility of implantation, should conception occur.

It is this third mechanism of action that lies at the crux of our debate.

There are a growing number of pro-life voices arguing that OCs cause abortions, and prescribing them is the equivalent of performing an intentional abortion. On the one hand, if oral contraceptives do cause abortions, then the vast majority of the medical community is deceived, their patients are misinformed, and even pro-life physicians are unwittingly prescribing abortifacients and killing innocent human beings. On the other hand, if oral contraceptives do not cause abortions, then the issue is a distraction that divides us and weakens our influence in defense of life. It is our hope that through reading this article, you will become familiar with the dilemma and understand how pro-life physicians who are convinced life begins at conception can disagree on this issue.

First, we will present the argument that oral contraceptives cause abortions. Those that believe that oral contraceptives may cause abortions have plenty of evidence that concerns and convinces them. There is an impressive amount of medical literature that claims that one of the ways oral contraceptives work is by preventing implantation of an embryo into the mother’s endometrium, which is the inner lining of the uterus. OC’s make the endometrium thinner, less glandular. In vitro fertilization studies have well-documented that thinner and less glandular endometriums are less receptive to a living embryo. If this secondary mode of action prevents implantation of the embryo and causes an abortion, then the oral contraceptive would not be acting as a “contraceptive” at all in this instance; that is, it would not be acting “against conception.” On the contrary, it would be acting as an abortifacient because it aborts a human being.

The literature acknowledges that preventing implantation is not the primary mode of action of OCs, but a secondary mode of action. The primary mode of action for an OC is to prevent ovulation. However, the medical literature documents an incidence of three to five pregnancies per 100 women per year for OC users; thus, they do not prevent ovulation 100% of the time. Though there are many studies that fail to show any ovulation at all even in estrogen doses even as low as 20 mcg, it has been shown that there are always a small percentage of women who, upon ultrasound examination, appear to be ovulatory on OCs, and those studies claim that even in such cases pregnancy is still prevented “because of other OC mechanisms of action, such as changes in the cervical mucus and endometrial lining.” (emphasis mine) (http://www.contraceptiononline.org/contrareport/article01.cfm?art=158) If the affect of the OC upon the endometrial lining is preventing “pregnancy” after the occasion of ovulation breakthrough and conception, it does so by an abortifacient, not a contraceptive mode of action. Women do get pregnant on an OC, so the endometrium is not rendered so hostile to the embryo that implantation is impossible, just less likely.

On the other hand, there is much medical literature that contradicts this notion that OCs cause abortions; unfortunately, however, not in terms that the pro-lifer can accept. Much of this contradiction in the medical literature is a result of an equivocation over the word “pregnancy”. The articles insist that an OC does not cause the abortion of a pregnancy, but they define “pregnancy” differently than those who argue that OC’s do cause abortions. The National Institutes of Health and the American College of Obstetricians and Gynecologists echo the consensus in the field of medicine: they insist that a woman is not “pregnant” until the embryo undergoes implantation, which happens about six days after conception! One of my patients informed me recently that her gynecologist insisted that the morning-after pill prevents pregnancy 100% of the time and does not cause abortions. This may be true given the gynecologist’s definition of “pregnancy”, but he is dead wrong in defining pregnancy as the stage after which the embryo has attached to the endometrium and she is dead wrong in implying from that this is when her baby’s life begins. Though designating this stage as the point at which pregnancy commences and life begins is convenient, it is arbitrary, palpably erroneous, and deceptive. Implantation into your mother’s uterus did not make you any more alive or human than did your first breath of air, your first meal, your first bowel movement, or any other arbitrary event in your life. (See the article “When Does Life Begin?” for further elucidation.)

For more thorough, scholarly literature that supports the view that OCs are abortifacient, we direct the reader to one of the following articles. One article by the Alan Guttmacher Institute, which is an organization dedicated to legal abortion, merits mention: “Preventing Pregnancy, Protecting Health: A New Look at Contraceptive Choices in the United States”, Harlap, Kost, Forrest, The Alan Guttmacher Institute, 1991, pp. 17-28.

Randy Alcorn, author of many books on pro-life issues, wrote a scholarly book entitled “Does the Birth Control Pill Cause Abortions.” A brief condensation of this book can be read on-line at http://www.epm.org/articles/bcp3300.html.

I include here three noteworthy articles published by physicians in defense of the position that OCs are abortifacient. Walt Larimore, MD, who is on staff with Focus on the Family and the Christian Medical and Dental Association, wrote an article in February of 2000 entitled, “Postfertilization Effects of Oral Contraceptives and their Relationship to Informed Consent.” It can be read at http://www.polycarp.org/larimore_stanford.htm. His article, “The Growing Debate About the Abortifacient Effect of the Birth Control Pill and the Principle of the Double Effect,” can be read at http://www.epm.org/articles/pilldebate.html. Dr. Larimore is very thorough in his review of the medical literature and of the ethical issues regarding the potential abortifacient effect of oral contraceptives.

Dr. William Colliton, MD, Clinical Professor of Obstetrics and Gynecology at George Washington University Medical Center and member of the American Association of Pro-Life Ob/Gyns (AAPLOG), published an article entitled, “Birth Control Pill: Abortifacient and Contraceptive.” This article was signed by twenty-six physicians, many with impressive credentials, and can be viewed on the website of the American Association of Pro-Life Ob/Gyns at http://www.aaplog.org/collition.htm.

In spite of the impressive voices that are speaking out about the abortifacient potential of OCs, there are many physicians who are convinced that life begins at conception and who do not believe that OCs are abortifacient. Undoubtedly the most common reason that physicians reject the notion that OCs are abortifiacient is that they have never before even heard of the notion. Textbooks employed in medical school as well as the lectures that medical students, residents, and interns hear during their training do not properly distinguish between contraceptives and abortifacients. During my training in medical school, my obstetrician professor insisted that the morning after pill did not terminate a pregnancy but rather worked by preventing a pregnancy. I publicly challenged him and he reluctantly admitted that the morning-after pill worked by preventing implantation of an already-conceived embryo, but he resolved the dilemma with the statement, “I don’t consider it much of anything at that stage.” It came down to his unsupported bias against the humanity of small human beings! Other tutors resolved the dilemma by arguing that it isn’t a “pregnancy” until it implants in the uterus, and so the morning-after pill works by preventing pregnancy, its abortifacient properties notwithstanding. One can easily see how confusion would abound under this type of irresponsible tutelage. Regardless, it is just a matter of time before patients who believe that life begins at conception win remarkable suits against their physicians for prescribing drugs to them like the morning-after pill that are unquestionably abortifacient without their informed consent.

A second reason that pro-life physicians may not hold the position that oral contraceptives cause abortions is that they are unconvinced by the evidence. There is ample data to support the first two method of actions of OCs mentioned above. But the third proposed method of action, the so-called “hostile endometrium theory”, has little direct evidence to support it. Drug manufacturers have heralded it from the beginning without proof, and it has been echoed by two generations of investigators without verification. There is indirect evidence that the OC produces a thinner, less glandular, less vascular lining, and there is direct evidence from the field of in vitro fertilization that a thinner, less glandular, less vascular lining is less likely to allow the attachment of the new human being when it enters the uterus. However, when a woman taking OCs does ovulate, the corpus luteum (the ovarian follicle turns into the corpus luteum after ovulation) produces ten to twenty times the levels of both estrogen and progesterone seen in a non-non-ovulatory pill cycle. This results in the growth of stroma, blood vessels, glands, and glandular secretions to help prepare the lining for implantation. If there is no conception after ovulation, the corpus luteum ceases to function about two weeks after ovulation and menses follows. However, if conception occurs following ovulation, the embryo releases the human chorionic gonadotropin hormone (HCG), which stimulates the corpus luteum to continue its function until the placenta takes over hormone production two months later.

The proponents of the “hostile endometrium theory” argue that OCs are abortifacient based upon the third mechanism of action. The medical literature clearly supports the claim that the uterus becomes thinner and less glandular as a result of the OCs, however, the medical literature comes to this conclusion from non-ovulatory pill cycles. It is assumed that this finding in non-ovulatory pill cycles would prevent implantation of the embryo conceived in an ovulatory pill cycle, but this presumption is false. If a woman on OCs ovulates and conceives, everything changes: through the HCG’s affect on the corpus luteum, and the corpus luteum’s release of high levels of estrogen and progesterone, the uterus is able to nourish its new guest very well.

It is noteworthy that in a normal menstrual cycle, on the day of ovulation, the endometrium is not receptive to implantation. If the embryo were to drop down through the fallopian tubes into the uterus on that day, it could rightly be called a “hostile endometrium”. But following ovulation, the corpus luteum transforms this hostile endometrium into a receptive, nourishing bed, where the embryo will attach about one week later after its trip through the fallopian tube, and where the baby will continue to develop until birth.

I include here a statement from pro-life Ob/Gyns, wherein they strongly disagree with those who purport that oral contraceptives cause abortions. This statement was sent to Randy Alcorn in response to his book, Does the Birth Control Pill Cause Abortions?

Pro-Life Physicians’ Statement to Randy Alcorn:

There are l,200,000 medical and surgical abortions of unborn babies that take place every year in the United States. The "hormonal contraception is abortifacient" theory is not established scientific fact. It is speculation, and the discussion presented here suggests it is error. How happy the abortionists must be to find us training our guns on a presumption, causing division/confusion among pro-life forces, and taking some of the heat off the abortion industry. Ought we not rather be spending our energies to eliminate the convenient destruction of the innocent unborn?

In Summary:
l. We know of no existing scientific studies that validate the "hostile endometrium is abortifacient" theory.
2. There is regular successful implantation of the invasive blastocyst on surfaces a great deal more "hostile" than "hostile endometrium" (e.g., fallopian tube lining). "Hostile endometrium" is not a demonstrated clinical reality.
3. The almost total absence of reporting of ectopic pregnancies associated with hormonal contraception would indicate the rarity of actual conception by patients using these modalities. (Minipill and norplant apparently are less effective in preventing pregnancies and ectopics).
4. Many factors play a part in how a family plans and spaces their children. It is not the purpose of this paper to promote, nor to oppose hormonal contraception. However, if a family, weighing all the factors affecting their own circumstances, decides to use this modality, we are confident that they are not using an abortifacient.
5. This paper is not meant to be the "final word" on this issue. If scientific study should validate that a hormonal contraceptive agent is partly abortifacient in its action, we would oppose that agent just as we oppose elective medical and surgical abortions.

We must constantly examine valid data as it becomes available in our effort to discern what is abortifacient vs. what is appropriate birth control to be used or prescribed by those who hold to the sanctity of human life from the time of conception.

Co-signators (alphabetically). All signators are specialists in obstetrics and gynecology, and a number have sub-specialty recognition and/or are on the faculty of teaching hospitals or Universities. This information may be distributed freely to Crisis Pregnancy Centers or other individuals or groups who may have an interest in the subject matter.

Watson A. Bowes,Jr,MD,Professor,Maternal-Fetal Medicine,Chapel Hill, N.C.
Matthew J. Bulfin, MD, general OB-GYN, Ft. Lauderdale, Florida
Byron Calhoun, MD, Maternal-Fetal Medicine, Tacoma, Washington
Steve Calvin,MD,Asst. Prof Maternal-Fetal Medicine,Minneapolis, Minnesota
Denis Cavanagh, MD, Professor, Gynecologic Oncology, Tampa, Florida
Curtis Cook, MD, Maternal-Fetal Medicine, Asst Clin. Prof, Grand Rapid, Mi.
Susan A. Crockett, MD, Assistant Clinical Professor, San Antonio, Texas
Steven Cruikshank, MD, Professor OB-GYN, Dayton, Ohio
Joseph L. DeCook, MD, general OB-GYN, Holland, Michigan
Bill Dodds,MD,Reproductive Endocrinology, Asso.Clin. Prof,Grand Rapids,Mi R.
Don Gambrell, Jr., MD, Clinical Professor, Augusta, Georgia
David Hager, MD, Professor/Consultant OB-GYN, Lexington, Kentucky
Donna Harrison, MD, general OB-GYN, Berrien Springs, Michigan
Camilla Hersh, MD, Clinical Professor OB-GYN, Vienna, Virginia
Antony Paul Levitino, MD, .Asso. Prof,.OB-GYN, Rensselaer, New York
Joe McIlhaney, MD, Obstetrician-Gynecologist, Austin, TX
Gwendolyn Patterson-Hobbs, MD, OB-GYN Clinical Associate, Vienna, VA
William Stalter, MD, Associate Clinical Professor OB-GYN, Dayton, Ohio
Roy Stringfellow, MD, general OB-GYN, Colorado Springs, Colorado
Robert L. Weeldreyer, MD, general OB-GYN, Holland, Michigan

January 1998

We also include a position statement from the Christian Medical and Dental Association on this issue:

Possible Post-conceptional Effects of Hormonal Birth Control

CMDA holds firmly that God is the Creator of life, that life begins at conception, and that all human life is of infinite value. We support measures to protect life from its earliest beginnings.

CMDA recognizes that there are differing viewpoints among Christians regarding the broad issue of birth control and the use of contraceptives. The issue at hand, however, is whether or not hormonal birth control methods have post-conceptional effects (i.e., cause abortion). CMDA has consulted many experts in the field of reproduction who have reviewed the scientific literature. While there are data that cause concern, our current scientific knowledge does not establish a definitive causal link between the routine use of hormonal birth control and abortion. However, neither are there data to deny a post-conceptional effect.

Because this issue cannot be resolved with our current understanding, CMDA calls upon researchers to further investigate the mechanisms of action of hormonal birth control.

Additionally, because the possibility of abortive effects cannot be ruled out, prescribers of hormonal birth control should consider informing patients of this potential factor.

We recognize the difficulties of providing informed consent while handicapped by lack of definitive information. However, counseling of patients may simply involve asking if they have concerns about potential post-conceptional effects of these methods of birth control. In cases where concern exists, an explanation may follow that includes the known mechanisms of action (e.g., inhibition of ovulation and decreased sperm penetration), as well as the concern about the unanswered question of whether hormones negatively effect the very early stages of life.

CMDA respects and defends the right of our colleagues to refuse to prescribe hormonal birth control when they do so with the concern of a post-conceptional effect.

We recognize that scientific reasoning is not the only factor that influences opinions about the use of hormonal birth control. But, while additional investigation is needed, current knowledge does not confirm or refute conclusions that routine use of hormonal birth control causes abortion. CMDA will continue to monitor new developments.

For a more thorough article attempting to refute the “hostile endometrium theory”, please see an article entitled “Hormone Contraceptives, Controversies, and Clarifications, authored by four Christian pro-life Ob/Gyns who are members of the American Association of Pro-Life Obstetricians and Gynecologists: http://www.aaplog.org/decook.htm.

There is a third reason that a pro-life physician who is convinced that life begins at conception may reject the notion that OCs are abortifacient: he is convinced that there are less, not more, unintentional abortions in woman on OCs compared to women who are not. For a drug to be classified as abortifacient, conception must occur, and the loss of these conceptions must exceed the baseline loss for populations not using the drug, or be shown to occur solely as a result of the drug. Even if there is a palpable accidental abortion rate on the OC’s through the third mode of action, this is much less frequent than the accidental miscarriage rate in the population of sexually-active women who are not on OCs. All things considered, there are less miscarriages in women on oral contraceptives than in women not on oral contraceptives.

If you would like to look at some precise calculations that do justice to this argument, click HERE.

Unlike combination OC’s, the morning-after pills or “emergency contraception” and IUD’s (Intra-Uterine Devices, devices which are implanted into the uterus), have a primary means of action to prevent implantation of an already-conceived human being. There is controversy about the morning-after pills, even among pro-life physicians who believe life begins at conception, because there is literature that insists that this modality acts primarily to inhibit sperm and egg transport, disrupt normal follicular growth, and block the leutenizing hormone surge that would result in ovulation. However, this would only inhibit ovulation if taken prior to ovulation, and if ovulation has occurred and conception has created a new life, then this acts primarily an abortifacient. Since the prescriber is unsure whether ovulation has occurred or is about to occur, he would be unsure whether the hormone would act by a contraceptive or an abortifacient mode of action. Therefore, we consider prescribing this modality to be a reckless disregard for human life and therefore the moral equivalent of a surgical or chemical abortion.

Similarly, the breakthrough ovulation rate of progestin-only pills is 40 % according to one reputable study, and ranges from 14 to 84 %, which means that a large portion of the effectiveness of this modality is dependent on the abortifacient properties of the hormone. Therefore, we consider prescribing progestin-only pills to be a reckless disregard for human life and therefore the moral equivalent of a surgical or chemical abortion.

This author is still evaluating contrary claims about the Depoprovera injection, and this article will be updated in the future with that information.

In conclusion, even in the pro-life community there is considerable disagreement on whether oral contraceptives cause abortions. It is the position of the Association of Pro-life Physicians that pro-life physicians can disagree on this issue, yet sincerely hold that life begins at conception and all intentional killing of innocent life is murder. Some APP physicians have no strain of conscience in prescribing oral contraceptives; others refuse to prescribe oral contraceptives, and still others are reluctant to prescribe oral contraceptives but are willing to prescribe the Nuvaring or the estrogen patches, which are unlikely to allow breakthrough ovulation. Hopefully, more concrete data will become available and pro-life physicians will become unified on this issue, but as for now we conclude that pro-life physicians who believe life begins at conception can disagree on the issue amiably.

Article by James P. Johnston, D.O., Updated January 7, 2005