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When Does Life Begin... and End with EPC's


Almost any current or former high school student can explain when life begins, although the recall of terminology may be imprecise. No credible scientist disagrees with the chronology found in standard biology textbooks. To understand the process, it's helpful to review fertility in women.

The monthly cycle:

Women, on average, have a 28-day cycle, though individual variations may be great. The cycle begins on the first day of menstruation. Soon afterward, the pituitary gland secretes follicle-stimulating hormone (FSH) which stimulates development and growth of an ovarian follicle and its ovum (also known as egg or oocyte). The follicle secretes increasingly high levels of estrogen, a hormone which stimulates the cervix to produce mucus which assists fertility. About one day before ovulation, estrogen levels peak and the pituitary gland then produces an increase in luteinizing hormone (LH). LH stimulates the follicle to release the ovum (ovulation).

Once released, the ovum will live no longer than about 24 hours, unless fertilized. After ovulation, the follicle (now called the corpus luteum) begins to secrete progesterone for 11 to 16 days ("luteal phase"). This hormone prevents further ovulation in that cycle, maintains the lining of the uterus, causes the cervical mucus to thicken or disappear, and closes the cervix. Estrogen levels fall rapidly after ovulation for 24 hours, then rise again, but are overshadowed by the much larger quantity of progesterone. Both hormones fall 2-3 days before the end of the luteal phase and then menstruation ensues.

Fertility is very low the first several days of the cycle. This period is followed by a fertile phase of 5 days of changing mucus, which culminates in the peak symptom and an additional three days, ending one or two days after ovulation. Maximum fertility is usually found from 2-3 days before the peak symptom to the day after it. The likelihood of pregnancy at peak and on the day of ovulation, is 30%; fertility ceases within three days after peak.

Why does the fertile period last 5-7 days when the egg's lifespan without fertilization is 24 hours? Because sperm can survive in cervical crypts for about five days, ready to fertilize an egg when it is released.


Once an egg is released from the ovary, it enters the oviduct or Fallopian tube, the conduit between the ovaries and the uterus. Sperm travel into the oviduct seeking an egg.

"Fertilization is a sequence of events that begins with the contact of a sperm (spermatozoon) with a secondary oocyte (ovum) and ends with the fusion of their pronuclei ... and the mingling of their chromosomes to form a new cell. This fertilized ovum, known as a zygote, is a large diploid cell that is the beginning ... of a human being." (Moore, Keith L., Essentials of Human Embryology. Toronto: B.C. Decker, Inc., 1988, p.2.) "Although human life is a continuous process, fertilization is a critical landmark because, under ordinary circumstances, a new, genetically distinct human organism is thereby formed. ... The combination of 23 chromosomes present in each pronucleus results in 46 chromosomes in the zygote. Thus the diploid number is restored and the embryonic genome is formed. The embryo now exists as a genetic unity." (O'Rahilly, Ronan and Müller, Fabiola. Human Embryology and Teratology, 2nd edition. New York: Wiley-Liss, 1996, pp. 8, 29). "Almost all higher animals start their lives from a single cell, the fertilized ovum (zygote). ... The time of fertilization represents the starting point in the life history, or ontogeny, of the individual." (Carlson, Bruce M., Patten's Foundations of Embryology, 6th edition. New York: McGraw-Hill, 1996, p.3.) "Embryo: An organism in the earliest stage of development; in a man, from the time of conception to the end of the second month in the uterus." (Dox, Ida G. et al. The Harper Collins Illustrated Medical Dictionary. New York: Harper Perennial, 1993, p. 146.) "The fertilized egg, now properly called an embryo, must make its way to the uterus." (Carlson, Bruce M., Human Embryology and Developmental Biology. St. Louis: Mosby, 1994, p.3). (See also prolife/issues/bioethic/fact298.shtml for numerous quotations from medical texts.)

Beginning about 6 days after fertilization, if conditions are ideal, the embryo will implant in the uterine lining (a process taking several days). The authors of Contraceptive Technology estimate that "approximately 50% of embryos do not survive" beyond two weeks even if no direct actions are taken to end their lives. This vulnerability has been posited as a justification for considering implantation the beginning of pregnancy, even the beginning of life. By this reasoning even lethal experiments could be performed on pre-implantation human embryos (or on newborn children in a region with high infant mortality!). Yet this fragile creature is indisputably human. His or her vulnerability should rather be a call for greater care than for annihilation.

What are hormonal ECPs?

The regimen approved by the FDA for post-coital "contraception" identifies six brands of ordinary birth control pills (OCs)—containing estrogen and progestin—and requires that a high dose of such pills be taken within 72 hours of "unprotected intercourse," followed by a second high dose 12 hours later. Preven, newly marketed by Gynétics and approved by the FDA in September 1998, is simply a kit containing the two high doses of OCs, plus a pregnancy test kit to rule out existing pregnancy from an earlier episode of intercourse.

How do hormonal ECPs work?

According to the FDA, "EC pills ... act by delaying or inhibiting ovulation, and/or altering tubal transport of sperm and/or ova (thereby inhibiting fertilization), and/or altering the endometrium (thereby inhibiting implantation)." (FDA, Federal Register Notice, Vol. 62, No. 37, Feb. 25, 1997). These properties of OCs have long been acknowledged, but it is impossible to determine which mode of action is responsible in any given cycle for a woman's failure to conceive or maintain pregnancy after "unprotected" intercourse. It is important to note that "ovulation is not always stopped, ... cervical mucus is not always made impenetrable, ... the lining of the womb is not always rendered unreceptive to a fertilized ovum every cycle, ... and Fallopian tube activity does not always inhibit sperm and ovum unification. ..." (Wilks, J., A Consumer's Guide to the Pill and Other Drugs, 2d edition. Stafford, VA: ALL, Inc., 1997. Numerous citations omitted.) Breakthrough ovulation and pregnancy occur even with "perfect" use of OCs. (Ibid., pp. 3-10).

Depending on where a woman is in her monthly cycle when intercourse occurs, and depending on the timing of the doses of ECPs, one might expect different modes of action to predominate. For example, for as many as 21 days of the average 28-day cycle a woman is normally infertile. Intercourse is not likely to produce a child, because there is no egg or imminent egg available to be fertilized. All modes of action may be present, including disruption of the next ovulatory cycle, but none is necessary to prevent conception, fertilization or implantation.

Once the fertile phase has begun, however, "taking a high level of estrogen via ECPs within 72 hours of intercourse ... may, in fact, precipitate ovulation. This would make it more likely, rather than less, that fertilization will occur," according to Dr. Klaus. In such a case, the risk of a potentially fatal ectopic pregnancy has also been shown to increase. (Morris, J.M. and G. Van Wagenen, "Interception: the use of postovulatory estrogens to prevent implantation," Am. J. Obstet. Gynecol., 115:101-6 (1973); Diana Rabone, M.D., "Postcoital contraception—coping with the Morning After," Current Therapeutics, p.46 (1990), cited in Wilks, op.cit., p.156)

Beginning four days before ovulation, the average likelihood of conception from intercourse jumps from 0% to 11%. It rises to 30% on the day preceding, and day of, ovulation, before dropping to 9%, 5% and 0% on the three subsequent days. ECPs taken promptly could fail to prevent fertilization and thus result in the death of an embryo who is unable to implant successfully due to ECP-induced changes in the endometrium.

If an ovum is in the Fallopian tube, the process of fertilization may begin within 15 to 30 minutes after intercourse. The "morning after" is already too late for any contraceptive effect to intervene. Thus some researchers conclude that "post-coital drugs act principally to terminate a viable pregnancy by interfering with the endometrium: ... 'this mode of action could explain the majority of cases where pregnancies are prevented by the morning-after pill.'" (Wilks, op. cit., p. 154, citing Grou, F. and I. Rodriges. "The morning-after pill; How long after?" Am. J. Obstet. Gynecol. 171:1529-34 (1994).)

How Effective are ECPs at Preventing or Interrupting Pregnancy?

The oft-cited 74% effectiveness rate for ECPs comes from a 1996 meta-analysis of ten clinical trials by Trussel et al. This percentage is the average of a range of effectiveness from 55.3% to 94.2%. A recent project in Washington State tracked demand, but did not report effectiveness. There, pharmacists collaborated in an Emergency Contraceptive Project sponsored by Program for Appropriate Technology in Health (PATH) and others. Under the project, trained pharmacists could write and fill prescriptions for ECPs. A reported 52% of women and girls seeking ECPs did so due to "contraceptive failure."

Another alarming aspect of the program is the demand generated by publicity. During their study, calls to the ECP Hotline increased ten-fold to 1,160 per month. More than 2,700 prescriptions were filled in the first four months alone. (HUMAN LIFE News, Sept.1998, p. 11, newsletter of Human Life of Washington.)

In an effort to determine whether women would use ECPs too often if they were allowed to keep them in their medicine cabinet, Anna Glasier, M.D. and David Baird, D.Sc. studied two groups of women in Edinburgh, Scotland. A total of 1,083 women were recruited who had previously used ECPs or had a surgical abortion. These women are "not exactly" a representative group, according to Margaret Pfeifer, M.D., an ob/gyn at the Mayo Clinic in Rochester, Minnesota. Because of their history of abortion or ECP use, they were more likely than other women to use ECPs. They also had a fairly high educational level and were given detailed written and oral instructions concerning use. Data was available for analysis on 1,071 women (549 with ECPs at home and 522 in a control group who would first need to obtain a doctor's prescription for ECPs). Among the treatment group, 47% used ECPs at least once in the two-year period of study, compared to 27% use among the controls. Ten percent of each group used ECPs more than once. One woman was dropped from the study after she used ECPs more than four times in four months. There were 28 pregnancies (5%) in the treatment group and 33 pregnancies (6%) in the control group. Eight women in the treatment group and four in the control group appear to have become pregnant during a cycle in which emergency contraception was used. The children who survived the ECPs were subsequently aborted. (Glasier and Baird, "The Effects of Self-Administering Emergency Contraception," N. Engl. J. Med., 339:1-4 (1998).)

What are the Side Effects of ECP Use?

About 50% of women experience nausea and 20% vomit. A far more serious side effect is the increased risk of ectopic pregnancy. The Princeton University website promoting ECPs also warns: "It is possible ... that a woman using ECPs could have one of the dangerous or even fatal complications that have been reported in very rare cases with normal, prolonged use of birth control pills. These include: thrombophlebitis (blood clots in the legs), lung clots, heart attack, stroke, liver damage, liver tumor, gallbladder disease, and high blood pressure" (

What are the Risk Factors for ECP Use?

Women who smoke cigarettes and those who have experienced any of the following conditions are advised not to take ECPs: blood clots in the legs or lungs, cancer of the breast or reproductive organs, stroke, heart attack, and "any serious medical disorder such as diabetes, liver disease, heart disease, kidney disease, sever migraine headaches, or high blood pressure" (http://opr.princeton. edu/ec/ecpnyou.html and

"Is it progress if a cannibal uses knife and fork?"

Stanislaw Lec

The marketing machine is now working nonstop. Pro-abortion groups hail the leap of progress for "women's rights." Professor Trussel, who manages an ECP website and hotline, explains he "want[s] to make emergency contraception the same household name that McDonald's hamburgers is." Print and radio ads, even free public service announcements abound. Commuters in Los Angeles are visually assaulted by billboards featuring a 40-foot high photo of a used, broken condom. We can't begin to compete with their resources. So it's up to every pro-life citizen, armed with the truth about ECPs' abortifacient potential, to present that truth in every appropriate forum, beginning with letters to the editor and articles or small ads in college newspapers. Otherwise the over-hyped and misleading marketing of ECPs will greatly increase their use, and cause a corresponding increase in lives lost to its abortifacient potential. 

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