William Cutrer, M.D.
From Family Building: Fact, Fallacy, and Faith
Hormonal therapies make up a large group of the contraceptive options. Combination Oral Contraceptives (COCs) (also known as “birth control pills”), progesterone only contraceptive pills (POCs), progesterone injections, and progesterone implants provide a variety of choices to those desiring fairly reliable contraceptive methods.
Other new methods of hormone delivery include using the estrogen and progesterone combinations as injections, skin patches (transdermal hormonal systems), or by insertion of a vaginal ring that allows the hormone to be released and absorbed through the vaginal walls. Some of these are already available in some places; others are approved for use in the near future.
The mechanism of action and potential side effects along with ethical concerns associated with these developing hormone delivery systems are similar to those for the pills, so we will consider them as a group. Those who use these techniques find them convenient and effective, but they bring with them some side effects and certain ethical issues.
The Physician’s Desk Reference (PDR), which contains detailed information about most pharmaceutical compounds, lists some serious potential side effects. These include blood clotting, strokes, liver tumors, and even death when taking medications that contain estrogen. The risks increase with age, making them poor choices for women over thirty-five, particularly if they smoke. (In all fairness it must be noted that some of these same complications are present with pregnancy as well, due to the highly elevated estrogen level. Risks associated with pregnancy include blood clotting, stroke, hypertensive complications, and even death. However, as with the pills, catastrophic complications are rare.)
Additionally, women have roughly one-tenth the circulating testosterone that men have, and COCs tend to decrease this hormone produced by the ovary. This can result in decreased oily skin and improvement of acne but may also dramatically lower libido. Some women on COCs note a substantial decrease in sex drive. Generally, this side effect can be overcome by changing the type of pill prescribed.
Other patients note spotting, headaches, nausea, and weight gain among the common side effects. The COCs often do not provide the same level of estrogen that the wife is accustomed to, so problems with vaginal dryness and decreased elasticity may require the addition of lubricants and a more patient approach to sexual intercourse.
All in all couples using this form of contraception report a high level of satisfaction, particularly because of the effectiveness of the COCs when taken correctly, and the “spontaneity” restored to the romantic experience.
Most companies report effectiveness approximating one pregnancy or less per hundred women years’ use. Of course this presupposes taking them correctly—every day at approximately the same time. Once a patient begins to skip the pills, her hormonal system will try to re-equilibrate and progress to ovulation.
How Does The Combination Pill Work?
Those who choose family planning must consider what available techniques fit within an ethical framework. This requires knowledge of biological systems and the mechanisms of action for each method. By far the most commonly prescribed hormonal approach is the combination oral contraceptive (COC).
Many preparations differ by dosage and packaging, but the key features are a “combination” of estrogen and progesterone. (Similar hormonal combinations are found in the new contraceptive patches, where the hormones are absorbed through the skin or via vaginal inserts.)
The pills are designed and intended to prevent ovulation, so this is the primary mechanism of action. If no egg matures and is released, there is no chance of fertilization or pregnancy.
A secondary mechanism of action involves making the cervical mucus thicker and thus less favorable to the passage of sperm into the uterus. Thus, if sperm can’t reach the egg, fertilization cannot occur.
Third, there is the possible slowing of the action in the tubes, which might alter the progress of the sperm or the egg, either interfering with fertilization or perhaps making implantation “out of phase.”
The fourth mechanism of action associated with COCs has generated considerable controversy, particularly in recent years, as dedicated physicians and researchers seek to resolve the conflict. The PDR has for many years listed as a mechanism of action the effect of the COCs on the endometrium, the lining of the uterus. The PDR reports that COCs make the lining of the uterus thinner and less favorable for the implantation of a pregnancy. If so, it would be possible that an egg could be released (escape ovulation—a known risk), and be fertilized in the tube only to have the embryo arrive at the uterus with an unfavorable endometrium. This would, in effect, cause a miscarriage.
In this scenario the pill would not prevent ovulation or conception, but rather it would prevent implantation, making it an abortifacient. Obviously this cascade of events has enormous implications both to pro-life physicians and patients. Those who believe this fourth scenario occurs or could occur argue forcefully that Christians should not use COCs, and that Christian physicians should not prescribe them.
Other equally well-trained, skilled clinicians and researchers believe the evidence demonstrates that this does not happen, or that the chance of it happening is more remote than the odds of being struck by lightning on a sunny day.
Who Is Right and What Should We Do?
I started medical school in the 1970s. Between then and now, I’ve heard many self-appointed “experts” declare that microwaves, sonograms, computer monitors, air travel (pressure changes), hot tubs, horseback riding, and lifting the arms above the head all cause first trimester abortions. Such advice was misguided as none of the above listed “warnings” has turned out to have sufficient evidence to condemn them.
As a result, many of us in medicine rely upon “evidence based” decision-making. That is, we try to have some convincing data before instituting a given therapy or rejecting an effective approach or treatment. For example a careful study of the PDR reveals that most medications now prescribed have not been “proven safe” in pregnancy because the cost of such research is prohibitive. So the PDR assigns them a “class category” that says they’re untested and thus not proven safe in pregnancy. Thus, the physician must decide if the benefits of any given medication choice outweigh the potential risks. Some antibiotics, most cold and flu preparations, and even nausea medicines haven’t been exhaustively studied in pregnancies such that a doctor could declare them “perfectly safe,” though we use them regularly when a legitimate need arises.
Some say we must take no risk with a woman who might be pregnant. So let’s consider how such a no-risk policy might look if consistently applied.
Certain viral infections can have a devastating if not fatal effect on the embryo. Must we therefore keep in isolation any woman contemplating pregnancy?
It is impossible to prove absolutely that there is zero risk associated with flying, cell phones, microwaves, and computers, though obviously any risk must be exceeding small. So do we avoid them at all cost because we believe in “no risk”?
As stated earlier, some researchers have found risks associated with natural family planning. There are risks associated with pregnancy, too. Even over-the-counter medications and “health foods” may carry some risk to the developing baby. So the key question is “How much risk is reasonable and acceptable?”
If we want to talk about risk to the embryo, consider the process of cryopreservation. Researchers now estimate that fully half the frozen embryos from infertility clinics will die during the thawing process before implantation is even possible. Yet many pro-life Christians support the practice of cryopreservation of embryos as reasonable and ethical. The goal or intent is to bear offspring, but the risk of using this technology is clearly much higher than that of pills.
Wisdom requires that when making informed decisions we consider the scientific data and opinions available to us, and that we respond prayerfully with faith, recognizing that the best scientific minds cannot yet agree. In the case of oral contraceptives complete data is unavailable. Other options for birth control may provide a safer and more ethical path than pills, but if the solution were totally clear at this time, Christian physicians would likely be much closer to consensus. However, that is not the case. So rather than issue a dogmatic pronouncement before the data can support it, we will explore the pros and cons of using COCs. In the process we recognize that for now, many Christian couples will have differences of opinion resulting in differing plans of action. Hopefully we can extend grace to those who evaluate the data and come to different conclusions from our own.
Arguments against using COCs. The PDR lists endometrial thinning and diminished implantation as one mechanism of action for these pills (and, as stated, has for years). In addition compelling scientific evidence tells us that the implantation of the embryo is a remarkably complex process. The embryo sends out “messenger signals” to the uterus signaling for the uterus to prepare for its arrival. Then some chemical messengers return and perhaps “woo” the embryo to the appropriate site.
Those who argue against using COCs point out that the entire process is delicate, having multiple essential steps. Thus, they say, if pill use alters the process and breakthrough ovulation still takes place, the chances that every step will be “rescued” in time for the embryo to implant and survive are minimal.
Multiple studies demonstrate that women on COCs have thinner than normal endometrial linings. (The endometrial lining is inside the wall of the uterus where implantation occurs.) This thinning is due to the level of hormones in the pills and the early presence of progesterone. Sonogram studies from infertility clinics show that a thinner endometrium may be less receptive to a pregnancy and thus more likely to cause miscarriage even before the woman knows she is pregnant.
Putting this information together, those who oppose COCs conclude that the pill can cause abortion, at an unknown rate. They then argue that any risk would be unacceptable, as other suitable methods of birth control do not put the embryo at risk. Arguments are made that we should “err on the side of life” and “trust God,” implying, perhaps unintentionally, that those who take pills fail to trust God and have a low view of the value of human life.
Arguments allowing the use of COCs. Other Christian physicians and researchers note that the “thinness” of the endometrium, when measured in women using birth control pills, is irrelevant. They reason that if breakthrough ovulation were to occur, that means the egg must have matured over time, a development that demands an increasing estrogen level. In other words if sufficient estrogen was present for ovulation to occur, then the ovary at ovulation would also release increased amounts of progesterone. (The ovary from the location where the egg was released produces progesterone.) Thus, the endometrium primed with estrogen and progesterone is sufficiently prepared for the embryo’s arrival, according to these experts.
Most of the physicians I know who practice Ob-gyn have delivered several babies conceived while the mother was on COC pills. These babies have done fine, and the risks of miscarriage or congenital abnormalities was no greater than that of the average population. In addition to prove that COCs were causing increased miscarriages, the number of pregnancies lost to women on birth control pills would have to exceed the number of miscarriages suffered by women not on pills. Thus, before the pill is rejected as abortifacient, the evidence must be sound and specific. To date no such data exists.
In addition all of us in Ob-gyn have seen embryos implant and grow in some very inhospitable places. Ectopic pregnancies have grown not only in the tube, but also on the ovary, on the intestine and even on the spleen—places without any endometrium at all! Thus, it seems obvious that if breakthrough ovulation does occur and fertilization does happen, the “abortifacient effect” on the endometrium cannot be absolute, nor does the embryo require a perfectly prepared endometrium to grow.
Some ask, “Why use these pills at all if the possibility for abortion exists?” Again, we could ask the same about sonograms, cell phones, and computers—why use them if the possibility of miscarriage exists? The PDR prescribing information that said COCs prevented implantation was not shown scientifically by supporting data thirty years ago when it was first listed, and even now researchers cannot yet demonstrate it conclusively.
So why was it listed? It would seem that in the manufacturer’s effort to make the pill look “sure fire,” this theoretical mechanism was added to the “mechanism of action” list. Yet the concern raised is legitimate and important, deserving of thorough investigation.
In the absence of demonstrable risk many use COCs because they are quite effective, reliable, convenient, and American women have used them for decades. However, patients should be informed of the current status of research, and alternate contraceptive approaches should certainly be considered.
Progesterone-only approaches. Pills, injections, and implants are available to those seeking a progesterone-only approach. Once again the primary mechanism of action is to suppress ovulation. Thus, if no egg is released, conception cannot occur and no ethical issues arise. Statistically, however, progesterone only pills (POPs) have a considerably higher breakthrough ovulation rate than COCs, and may thus be riskier approaches from the perspective of possible abortifacient action.
A patient on POPs would have an endometrial lining that is certainly thinner, with no estrogen priming it for implantation. Once again, for break-through ovulation to occur the ovary would have to increase its own estrogen production and as a result progesterone would indeed rise after ovulation. Would this be sufficient to prevent the “hostile endometrium” that might lead to spontaneous miscarriage? No one can say with certainty, but since the escape ovulation rate may be as much as ten times higher for POPs than with COCs, special consideration should be given before beginning these.
Some physicians use the POPs only when a new mother is nursing to provide added protection. Most women do not ovulate while nursing during the first few weeks if they are doing around-the clock breastfeeding, but it is difficult to predict when that first fertile egg will be released. I had a patient who conceived again by her six-week check-up despite the fact that she was nursing; so one should not rely on nursing alone to have a contraceptive effect if family spacing is the goal. The precise likelihood of a nursing mother ovulating while on the POPs remains unknown.
Other Progesterone Only Approaches. Progesterone shots, given roughly every three months, are quite effective contraceptively because the dose appears sufficiently high to suppress ovulation. The shots, used extensively in other parts of the world, are inexpensive. However, a significant drawback involves the patient’s inability to resume ovulation predictably. Some women may stop the shots and not ovulate again for a year. And once the injection is given, there is no way to retrieve the medication should the couple change their minds and desire to attempt to conceive. Many of these women can take medicine to “override” the progesterone, but this is unreliable.
Norplant, the delivery system that puts the progesterone in tiny plastic rods surgically placed just under the skin, is similar to the POPs in the potential for escape ovulation. The pregnancy rates are quite low on Norplant, and it provides continuous protection. Additionally, many women reject this technique because of the unpredictable (though light) bleeding that users often experience. The system costs significantly more than the shots, but it lasts for up to five years. Norplant rods can be removed at the patient’s discretion and menstrual periods generally resume fairly quickly.
The above hormonal approaches are designed to work by preventing ovulation. However, another available hormonal technique uses the same hormones in higher dosages post-ovulation to intentionally prevent the early embryo from implanting into the uterus. Thus, it works by interrupting pregnancy, as conception has already occurred.
Morning After Pill. The so called “morning after pill” is actually a series of combination oral contraceptives (COCs) taken in such a way that they significantly increase the patient’s estrogen and progesterone, and then withdraw the hormonal support abruptly. (Ordinarily this means taking certain types of pills in multiples on one day, and then nothing the next.) This approach will prevent ovulation if it hasn’t already occurred, which is ethically acceptable. However, it will then cause a mini-period, sloughing off the endometrial lining, which prevents an embryo from implanting if conception has already occurred. That is, if pregnancy resulted from the sexual exposure because the egg had already been released, this dosage of hormones would abort the embryo without the patient’s knowledge—an unacceptable option from the standpoint of sanctity of life.
Personal Summary of Hormonal Contraception
Most of the Christian physicians with whom I’ve spoken agree that doctors should inform patients of the possible mechanism of action for each hormonal approach. I fully agree. Patients deserve the opportunity to make informed decisions on the basis of existing knowledge. COCs may one day prove to have a risk ratio that is sufficiently high to warrant a strong statement against their use. We must be open to further investigation.
Personally, I believe the evidence against the COCs is compelling, though not yet convincing. I believe the evidence should be carefully considered and at this writing, while I don’t think COCs should be rejected completely, couples should at least consider alternate approaches to family building. For those who chose to use COCs in the past, there is some encouragement in the current evidence that cannot clearly demonstrate an abortifacient mechanism. We try to make informed decisions on the basis of what we know, recognizing that further developments may require reconsideration.
I am personally concerned when I hear others labeling COCs as “abortifacients.” As this category of hormonal approach has many other medically appropriate applications, I would hate to see women avoid taking the pills because of a theoretical possibility of risk when they may have a legitimate indication for therapy with a hormone combination approach. For example the pills are sometimes effective in treating benign ovarian cysts and managing the progression of uterine fibroids or pelvic endometriosis. And COCs may be helpful in management of abnormal hormone production from the ovaries, resulting in excessive hair growth or difficult-to-treat acne. While some of these indications may seem unimportant, I found various pill formulations to be quite versatile in gynecologic practice totally apart from the contraceptive question. Thus, as information about COCs’ risk/benefit data becomes clear, we must not assume there is no place for combination hormone treatments.
As for the POP, I’m not inclined to use this approach. Each couple should be aware that POPs pose at least a theoretical risk to the embryo, though we simply don’t have enough evidence yet to know if the risk is one in a thousand women years of use or one in a million. However, any couple choosing to use hormonal approaches to family spacing should commit to taking them properly and regularly, as prescribed.
Excerpt from Family Building: Fact, Fallacy, and Faith (Aspire). Copyright 2002 William R. Cutrer with Sandra L. Glahn. All rights reserved.