The Roman Catholic Church’s official policy on the ‘regulation of birth’ is, of course, that artificial birth control should not be used since the practice transgresses God’s ‘natural moral law’ to go forth and multiply (and, of course, with congregation numbers already being as low as they are, well…). Therefore, “direct interruption of the generative process already begun…[is] absolutely excluded as lawful means of regulating the number of children.”
The one loop-hole, however, is the rhythm method — refraining from sex during a woman’s fertile period — one of those handy laws of nature which “God has wisely ordered.” If you and your wife/husband just make sure to have sex only at those times when she’s/you’re less likely to get pregnant, then you can have your cake and eat it, too — avoid unwanted prenancies, while not interfering with conception or having to opt for a selective abortion. (The rhythm method, by the way, is estimated to be anywhere from 75-90% effective in avoiding unwanted pregnancies.)
However, in a forthcoming article in the Journal of Medical Ethics, Luc Bovens suggests that the rhythm method may work not (only) because it prevents conception from happening in the first place, but rather because those embryos conceived during a woman’s less fertile period are actually less viable. Both the sperm and the egg may be old and the uterine lining may not be optimal.
In the article [not yet available], Bovens offers some estimates of how many naturally aborted embryos we might be talking about — the upshot is that he reckons that for every one unplanned pregnancy in rhythm method users in ten woman-years, there would also be two to three embryonic deaths. Even though the actual numbers can be disputed, the logic of the argument seems pretty sound (Bovens, via email):
“If there is reduced viability for embryos conceived outside the abstinence period for rhythm method users, then the method is likely to be effective, not only because it reduces the chance of conception, but also because embryos so conceived have a lower viability. And hence for every failure of the rhythm method (i.e. for every pregnancy) there is a higher rate of embryonic death.”
If Bovens is right — and if (to paraphrase) every embryo is indeed sacred — rhythm method users may need to re-evaluate their ‘moral choice’.