The mode of action of [emergency contraception, EC] has become he subject of heated debate in North America and in several Latin American and Caribbean countries. The main question is centred on whether or not EC prevents pregnancy by interfering with post-fertilization events. This issue is of importance for many people who consider that a new human life begins at the time that fertilization is completed. Accordingly, interference with post-fertilization events would lead to loss of human life. In spite of a lack of scientific evidence to support a post-fertilization effect, this possibility is used as an argument to turn legal, political and religious constituencies against the availability and use of EC. (Ortiz, et al, 2004)
In order to satisfy my own curiosity and my critics, I’ve reviewed recent scientific literature related to the question of whether or or not Plan B is abortifacient. I do not wish to appear to be in any way “rooting” for Plan B and/or its supporters. I am not. However, I have been very frustrated by the way that many of my fellow pro-lifers have repeatedly stated confidently that Plan B sometimes acts after fertilization and is therefore abortifacient. I do not believe such confidence is supported by scientific evidence. The goal of this literature review is to present a fair appraisal of the likelihood of postfertilization effects caused by Plan B to the pro-life community.
For the most part my analysis will proceed in chronological order, but I’ll begin with a newer article (Croxatto, Ortiz, and Müller, 2001) that provides an brief primer on the relevant reproduction science. Continue reading →
Per my request, with intercessory help from Gregory Popcak, Kevin Miller at Heart Mind and Strength has posted clear and consise rebuttals that address the scientific and bioethical claims made by Bovens. Kevin has degrees in biology, chemistry, and moral theology, so he knows his stuff. He also got to the point much more quickly than did (Part I, Part II). 😉 Tolle, lege.
Having used what he believes to be sound reasoning to implicate NFP in avoidable embryo deaths, he then entertains some possible pro-life responses. Since there’s little actual reasoning in Bovens arguements, I’d just as soon skip his charicatures of pro-life rebuttals. However, since they involve subtle changes to his arguments and could easily stand on their own, I’ll briefly address them, if only to highlight his slight of hand.
"So what is the alternative? If one is concerned about minimising embryonic death, then one should avoid types of contraception whereby each unintended pregnancy (due to its failure) comes at the expense of a high embryonic death rate. Given our first assumption, a condom user (who makes no distinction between HF and non-HF periods) can count on one embryonic death for each unintended pregnancy. A rhythm method user, however, should count on two to three embryonic deaths for each unintended pregnancy. Assuming a success rate of 95% for condom usage, we can count on an expectation of .5 pregnancies in 10 years. Hence, the expectation of embryonic death is .5 per ten years for a condom user, which is substantially lower than the expectation of two to three embryonic deaths per ten years on the rhythm method. Even a policy of practising condom usage and having an abortion in case of failure would cause less embryonic deaths than the rhythm method."
"So how can this argument be blocked? First, one could say that the empirical data are questionable. However, the result really depends on the simple assumption that embryos conceived outside the HF period are less viable than embryos conceived during the HF period. If this is the case, then the success of the rhythm method is contingent on a higher embryonic death rate and so every pregnancy due to a failure of the technique will come at the expense of a higher embryonic death rate—and this is all that is needed to get the argument off the ground."
"Some proponents of the pro-life movement argue against morning after pills, IUDs, and contraceptive pills on grounds of a concern for causing embryonic death. What has gone unnoticed, however, is that the pro-life line of argumentation can be extended to the rhythm method of contraception as well. Given certain plausible empirical assumptions, the rhythm method may well be responsible for a much higher number of embryonic deaths than some other contraceptive techniques."
Though some responses to the sloppy arguments made in this paper have been made by American Papist, Epiphany, and other bloggers, I do not believe the responses I’ve so far seen address the scientific/statistical aspects of Bovens’ claims. For instance, they rightly point out that the rhythm method was long ago replaced by much more reliable empirical methods collectively known as natural family planning (NFP). However, I suspect that Bovens chose to deliberately seem ignorant of pro-life/anti-contraceptive terminology in order to subtly mock what he sees as ignorance of reproductive medicine on the part of those who call the birth control pill abortifacient. I fear that Catholic bloggers have allowed themselves to be distracted by a red herring.