Much Ado About Nothing: Pro-Life Misconceptions About Contraception

One of the most amazing things about the stir caused by the recently leaked HHS proposal is how little, make that no, effort has been made to investigate whether the claim by the anti-abortion establishment about the mode of action of hormonal birth control is even true. A subsequent draft of the regulations without the redefinition of abortion has been released, but the underlying question — can contraception prevent implantation? — still stands.

Now, of course, for pro-choice people, this is a moot point. Even if hormonal birth control could prevent a fertilized egg from implanting in the womb, that’s not abortion because pregnancy doesn’t begin until implantation. To enter into this discussion is to first set aside the medical and legal definition of pregnancy and indulge the extremists. That’s why this discussion never really happens. But what would we find if we did indulge them?

According to the Code of Federal Regulations, The American College of Obstetricians and Gynecologists and the National Institutes of Health, pregnancy begins when a fertilized egg implants in the womb. Until it affixes to the woman’s womb a fertilized egg can not receive nutrients from the woman’s body, which is essential for it to grow. Implantation is also the only way in which a pregnancy can be determined, there is no test that can tell when an egg has been fertilized—there is no way of knowing whether or not this has happened.

Implantation is what sets in motion all the signs that pregnancy has begun. On this one point, science, medicine and the law agree: implantation is the moment at which pregnancy starts. The only dissenting group is the pro-life movement, which dismisses this definition. It, instead, would like pregnancy to start at the unknowable moment the sperm fertilizes an egg. Once sperm meets egg, any effort to prevent the egg from implanting in the womb is considered an abortion by the pro-life movement. This is one of the arguments they offer up as justification for the campaigns to keep women from using birth control. Their claim is that most birth control methods prevent fertilized eggs from implanting in the womb, which to them, though not to science, is an abortion. But even that is not true. There is no evidence that birth control methods actually do what pro-life groups claim.

Prompted, in part, by the growing efforts of anti-abortion groups to define birth control as abortion, the American Journal of Obstetrics and Gynecology in 1999 reviewed the available research on “the mechanism of action” of the contraceptive methods that so dismay pro-lifers. The authors take up the pro-life concerns directly writing, “Recently, some special interest groups have claimed, without providing any scientific rationale, that some methods of contraception may have an abortifacient effect.”

After reviewing the available literature, the authors conclude that hormonal contraceptive methods (oral contraceptives, the patch, the ring, the shot) cause a number of changes in a woman’s body which prevent
pregnancy. Primarily, what they do is simply prevent ovulation. In other words, take the pill and in almost all instances a woman won’t release an egg. No egg, no chance of pregnancy. The secondary way these contraceptives function, the authors report, is by preventing fertilization. So, on the very slim chance that a woman using a hormonal method does produce an egg another mechanism of action kicks in. Hormonal contraceptives also thicken the mucus lining of women’s reproductive organs which hamper the ability of the sperm to even get to the egg. And if a rogue sperm reaches the egg, hormonal contraceptives prevent it from penetrating the egg. Specifically, they stop the shell encasing the egg from disintegrating so a sperm can’t actually do the deed of fertilization. This is what is known about how hormonal birth control works.

What gets pro-lifers so worked up is that they insist on believing that a fertilized egg can be stopped from implanting in the womb. First off, hormonal contraceptives stop fertilization. What if, through some extraordinary, unknown, and seemingly unknowable process, an egg got fertilized? The researchers
consider the question and report , “No direct evidence exists showing that implantation is prevented by progestin-only methods” and “The evidence does not support the theory that the usual mechanism of action of IUDs is destruction of fertilized ova in the uterus,” say the authors. After reviewing all the research available on the modes of action of all contraceptives in question the authors summarize their report by explaining that “Even though the precise mechanism of action of modern contraceptive is not yet fully known, scientific evidence suggests the main mechanisms of action for each method. Inhibition of ovulation and effects on the cervical mucus are the primary mechanisms of the contraceptive action of hormonal methods. Evidence indicates that the primary mechanism of action of IUDs is the prevention of fertilization.”

“All of these methods, directly or indirectly, have effects on the endometrium [the lining of the uterus] that might prevent implantation of a fertilized ovum,” the researchers acknowledge. But as they quickly point out, “So far, no scientific evidence has been published supporting this possibility.” There’s just no evidence that any birth control method prevents a fertilized egg from attaching to the womb, even though that’s the basis for the pro-life claims.

What’s most striking about all this, is that, really, it should be a relief to pro-lifers. Birth control doesn’t have any effect on the egg once fertilized. The primary and secondary ways in which these methods work should be completely acceptable by the pro-life movement. In fact, though, they’ve taken just the opposite stance. Their argument usually sounds like this: We can’t really know for sure that in some cases, however rare, a
fertilized egg isn’t kept from fulfilling its God decreed destiny of implanting in the womb. And the dutiful scientist, limited by the research facts, must acknowledge that though there is no evidence to suggest that such a thing happens, it’s impossible to rule it out. So there! Says the pro-lifer. It can’t be ruled out. You can’t prove a negative. It’s a little bit like deriding gravity as a hypothesis. Yes, the last ten times you dropped that spoon, it crashed down on the table. But what about the eleventh time? Or the eleven  hundredth? Or the eleven millionth? There is also know way of knowing how breast feeding works as a means of birth control, which it does in the exact way hormonal methods menitioned above do, or whether fertilized eggs to breast feeding women are prevented from implanting. Applying the same exact standard here, pro-lifers would even be against the birth control method God designed. They propagate “education” campaigns, with great vehemence and assuredness, about the “abortifacient” method of birth control—all this, because while there is no evidence to show these methods actually prevent implantation of a fertilized egg, there is also no evidence to show they do not. “Insufficient evidence exists on whether cellular or biological changes in the endometrium could actually prevent implantation,” say the authors. However, their point is that it doesn’t matter. “The possibility of fertilization during combined oral contraceptive use is very small. Hence, endometrial changes are unlikely to play an important role, if any, in the observed  contraceptive effectiveness of combined oral contraceptives.” Thus pro-life campaigns against birth control are based not on scientific evidence, but rather on wishful thinking. Indeed, on a slim hypothetical chance, the pro-life movement has successfully opposed legislation that would have provided millions of women access to effective birth control methods. If the science isn’t on your side, then, the pro-life side seems to believe, ignore it.

Even some pro-life physicians, sparked by the recurring actions by the pro-life movement as a whole against birth control, stepped in to offer their medical views on the concerns their fellow pro-lifers raise. In 1998, twenty-two pro-life Ob/Gyns published an analysis entitled “Birth Control Pills: Contraceptive or Abortifacients?” and four of these pro-life physicians followed up with a more detailed paper on hormonal
contraceptives in general. The physicians open their statement boldly warning, “Currently the claim that hormonal contraceptives [birth control pills, implants (norplant), injectables (depoprovera)] include an abortifacient mechanism of action is being widely disseminated in the pro-life community. This theory is emerging with the assumed status of “scientific fact,” and is causing significant confusion among both
lay and medical pro-life people. With this confusion in the ranks comes a significant weakening of both our credibility with the general public and our effectiveness against the tide of elective abortion.” The authors explain that any effects on the uterine lining that the pro-life movement uses to support the claim that fertilized eggs are being prevented from implanting would be insignificant and has no role in the ability for a fertilized egg to implant. Fertilized eggs are able to implant in much more hostile conditions than those resulting from the mode of action from the pill. They report “The presumption that implantation of a blastocyst is thwarted by “hostile endometrium” is contradicted by the “pill pregnancies” we as physicians see. Pill company literature estimates 3 to 5 pregnancies per l00 women per year for pill users. Many of these women take the “pill” an additional month or two before finding out they are pregnant. These pregnancies generally progress with no more difficulty than non-pill pregnancies. To our knowledge, there are no studies showing that the spontaneous abortion rate in these cases is any greater than in pregnancies with a “friendly endometrium.” The pro-life physicians conclude that there is no evidence to support that the contraceptive methods in question act in the ways that would be unacceptable to the pro-life individual who
believes life begins at fertilization. They state it as plainly as they can, “the ‘hormonal contraception is abortifacient’ theory is not established scientific fact. It is speculation, and the discussion presented here suggests it is error” and continue “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.”

Yet, their campaigns against birth control continue today with more intensity than even before this  intervention from the most expert on the pro-life side. Of course, arguing over inconvenient biological truths is, in many ways, besides the point when it comes to pro-life disenchantment with birth control. Don’t be
misled. This fracas is not caused by a simple scientific misunderstanding. Otherwise, they’d rush to support birth control methods that don’t ’cause abortions,’ even in their implausible view. Like the diaphragm, condom, cervical cap, and spermicides. But the pro-life forces aren’t on record anywhere in favor of methods that keep sperm and egg apart. It appears impossible to find a single instance in which a pro-life group has anything good to say about any birth control method except natural family planning—a technique most notable for its high failure rate. Remember, even the lowly condom disturbs them.

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  • amanda-marcotte

    If you can turn any kind of contraception into abortion through wishful thinking, then why don’t they claim condoms are abortion?  I can only figure that they’re more interested in banning the kinds of birth control women can use without relying on male cooperation first.

  • invalid-0

    the pro-fetal-life movement doesn’t really make the claim that condoms, themselves, are “abortificient.” What happens is another change in the basic argument. A very vocal minority of the PFL movement believes, emphatically, that anything you do to prevent pregnancy gives you the wrong mindset. Decisions of pregnancy are up to God, not we mere mortals actually effected by them. So, if you use some method (particularly a method developed by human scientists) to prevent pregnancy, you are living antithetical to God’s will.
    There’s a handbook for PFL’s produced by ALL that explains this slipper-slope fallacy for their followers. Basically, any attempt to separate “God’s will” from your life is a big no-no and you’re no different than the stereotypes they create about Women aborting multiple times for “superficial” reasons.


  • invalid-0

    And with hormonal and IUD’s a woman can separate BC from sex–something that you can’t do with other methods–heaven forbid that couples can actually enjoy sex without thinking about the connection! Also if they are so worried about abortion aren’t they encouraging tubals and vasectomies for those who have all the children they want? With these permament methods there is no concern about the egg geting fertilized. I do want to say though that it does not help to be against NFP-it does work if used consitently, though I don’t see how that doesn’t go against their God’s will since a couple is deliberately having sex when NOT fertile.There are resources available for those who want to understand how their fertility works without the CAtholic crap. And it is very woman friendly–when I followed it we could do anything but intercourse when fertile which is often more enjoyable for the woman anyway. The Catholics of course think oral sex or mutual masturbation are “icky” (a term I actually heard used!). I am so happy to now be in menopause–yeah! But am I thwarting Gods will by having sex knowing I am NOT fertile!!

  • sayna

    …I don’t see how that [NFP] doesn’t go against their God’s will since a couple is deliberately having sex when NOT fertile.

    Exactly! That’s what I’ve been wondering. Not only are they creating the possibility that an egg may be fertilized but unable to implant, but they’re actively trying to prevent pregnancy. Why is that any different?

  • invalid-0

    There is also know way of knowing how breast feeding works as a means of birth control, which it does in the exact way hormonal methods menitioned above do, or whether fertilized eggs to breast feeding women are prevented from implanting. Applying the same exact standard here, pro-lifers would even be against the birth control method God designed.

    The “Quiverful” movement – fringe even by pro-life standards, yes, but they’re out there – actually does teach that children should not be breastfed past about 1 month in age, if at all, because of the inhibition of the mother’s fertility. (I guess if your children aren’t 11 months apart in age you’re doing it wrong?) But that seems to me to support a statement that they’re not interested in a woman’s role as a mother, but in a woman’s role as a vehicle to carry her uterus around.

  • mh


    The whole worry about abortifacients was started by the pamphlet included with every birth control pill prescription, which claims that the pill can thin the uterine lining and prevent a blastocyst from implanting. Check your own pills if you don’t believe me. There is (or was a couple years ago) a pamphlet included by the drug company making exactly that claim.

    Here is a pro-choice feminist MD who is very up-front about admitting that the pill can prevent implantation:

    She writes: 


    "Other effects of the pill can either reduce sperm motility or thin the uterine lining — all simply to keep a fertilized egg from implanting if ovulation does occur."

    She goes on to say that this does not terminate a pregnancy because pregnancy begins at implantation.

    But it does destroy the blastocyst. Pregnancy may be undetectable between fertilization and implantation, but a lot goes on in between. Contrary to your claim, the egg does grow before implantation. A fertilized egg is not what implants. It is a blastocyst by then, consisting of a dozen or so cells, each with the new genetic code derived from both parents. So it’s already growing at that point, and therefore, alive.

    It used to be said that life begins at conception and conception was understood as the union of sperm and egg. It was recognized early on that some semantic tricks would be needed in order to facilitate social acceptance of hormonal birth control. From Wikipedia:


    ‘In 1959, Dr. Bent Boving suggested that the word "conception" should be associated with the process of implantation instead of fertilization.[12] Some thought was given to possible societal consequences, as evidenced by Boving’s statement that "the social advantage of being considered to prevent conception rather than to destroy an established pregnancy could depend on something so simple as a prudent habit of speech." In 1965, the American College of Obstetricians and Gynecologists (ACOG) adopted Boving’s definition: "conception is the implantation of a fertilized ovum."[13]’

    I have never heard the claim that the pill can prevent a sperm from penetrating the shell of the egg. Maybe by weakening the sperm, I suppose. But I think you should document that claim because it is pretty unusual.

    I certainly don’t agree that the issue need not concern pro-choicers, unless you wish to make the claim that all pro-choicers would accept frequent, repeat, early abortions as a method of birth control.

    I agree that it is still uncertain whether the pill ever does act to prevent implantation and, if it does, how frequently. Because it’s generally impractical (NOT impossible) to detect conception pre-implantation, it’s hard to see how this could be quantified. Therefore, there is definitely room for debate in both pro-choice and pro-life circles as to how much this should concern us. 

    But in any case, you are very wrong to suggest that the abortifacient claim is patently groundless. The issue and the drug company’s semantic strategy for neutralizing it is well documented since 1959 and it doesn’t take a lot of research to learn the actual facts.

    I would be interested to hear your thoughts.


    • invalid-0

      m.h., the statements in the article above were culled from a review done by the American Journal of Obstetrics and Gynecology in 1999 on the available research on “the mechanism of action” of contraceptive methods available then. are you suggesting that one MD’s opinion outweighs that of mutiple peer-reviewed studies? what a fallacious arguement.

  • invalid-0

    I guess that everytime you get your period you werent trying hard enough and killed a possible baby, since oyu could possibly have had sex and gotten pregnant with the egg.
    People need to chillax and focus on their own uterus.