The February 2015 Linacre Quarterly (the official journal of the Catholic Medical Association) features a groundbreaking study by Chris Kahlenborn, MD of The Polycarp Research Institute titled Mechanism of action of levonorgestrel emergency contraception. The study, contrasting the theoretical basis on which emergency contraception (otherwise known as “Plan B”) is claimed to function with the facts and statistics of the most recent research outlining the mechanism by which they cause early abortions, is sure to cause heartburn among Catholic bishops and ethicists who, based on scientific thought and bioethics theories several decades old, continue to permit their use in Catholic institutions.

The study’s abstract lays out the serious nature of the debate right up front:

… Proponents of LNG-EC have argued that they have moral certitude that LNG-EC works via a non-abortifacient mechanism of action, and claim that all the major scientific and medical data consistently support this hypothesis. However, newer medical data serve to undermine the consistency of the non-abortifacient hypothesis and instead support the hypothesis that preovulatory administration of LNG-EC has significant potential to work via abortion. The implications of the newer data have important ramifications for medical personnel, patients, and both Catholic and non-Catholic emergency room protocols.

I interviewed Dr. Kahlenborn about his study for 1P5 via phone and email correspondence:

1P5: Dr. Chris, can you give us a quick overview of the study and its findings?

Chris Kahlenborn, MD: Our article is a review of the most recent medical data to date, which strongly support the assertion that Plan B is an abortifacient, especially when given prior to ovulation.   Two other recent papers also strongly support an abortifacient method of action of LNG-EC (Peck et al, 2013 and Raviele, 2014).  Simply put, the evidence supporting an abortifacient effect of LNG-EC is clearer and more compelling than ever before.  Certainly any claim of “moral certainty” regarding a non-abortifacient method of action no longer has credibility.  Indeed, given the strength of the most recent evidence, the nomenclature of emergency contraception should be changed to emergency contraception/abortion and this should be reflected in Catholic/pro-life and the secular literature as soon as possible.

1P5: Does Plan B ever act as a contraceptive?

Chris Kahlenborn, MD: Ideally, Plan B should be named emergency abortion/contraception instead of emergency contraception, because it has high potential of working as an abortifacient when given prior to ovulation.  We noted in our paper that when given prior to ovulation, Plan B frequently allows ovulation to occur and has no major impact on sperm flow or quality, yet one does not see any evidence of clinical pregnancy.  If both sperm and an egg are present and one does not see evidence of clinical pregnancy, then abortion is the most likely mechanism of action.  In the minority of cases, when Plan B truly stops ovulation, it likely works via a contraceptive method.

1P5: Your paper goes into great depth regarding the issue of when Plan B is taken, including the fact that taking it on the day of ovulation essentially renders Plan B completely ineffective.

Chris Kahlenborn, MD: Yes, it appears to be useless or actually may increase a woman’s risk of getting pregnant when taken on or after the day of ovulation, according to the data presented by Dr. Noe in her 2010 and 2011 studies (Contraception).  Other leading researchers such as Dr. Trussell and Davidoff also raise this very real possibility: “it even raises the counter-intuitive but undocumented possibility that Plan B used after ovulation might actually prevent the loss of at least some of the 40% of fertilized ova that ordinarily fail spontaneously to implant or to survive after implantation.” (JAMA, October, 2006).   In practical terms this means that while Plan B likely often works by abortion if given prior to ovulation, it has either no efficacy or actually could have a pregnancy enhancing effect if given on the day of ovulation or after.

1P5: What is the history behind the Church’s position on emergency contraception?

Chris Kahlenborn, MD: In 1995, then Bishop Myers, accepted what is known today as the “Peoria Protocol,” which, in a nutshell, states that it is okay to give Plan B to women who have been raped if it is given prior to ovulation, since it is based upon the assumption that Plan B consistently stops ovulation in this phase – which it clearly does not, as noted by the most recent research and even admitted to by the most notorious Plan B advocates/researchers (eg, Horacio Croxatto, MD and James Trussel, PhD).

Many Bishops have accepted this protocol while others have remained skeptical.  Unfortunately, we now know from several large studies such as that of Dr. Croxatto (Contraception, 2004), that Plan B does not consistently stop ovulation.  Therefore, the entire Peoria Protocol is based on a faulty premise.

For years now, liberal theologians have given liberal Bishops the cover they need to permit this faulty protocol. In this age where so many Bishops are afraid to stand up for the Church’s harder teachings, it’s hard to believe that they will stand up based on the findings of our paper, especially since the press will try to paint courageous Bishops as “endorsing rape.”  But with the publication of this paper there is now something different.  Now, it is no longer a question of theology — actually it never was — but a simple matter of the science supporting an abortifacient mechanism of action.

1P5: Does this mean that Catholic hospitals who currently allow Plan B or other emergency contraception are allowing abortions to occur? 

Chris Kahlenborn, MD: The answer to this is almost certainly yes, and I say “almost certainly” because at this point in time it is difficult to measure the frequency of abortions, given the small size of the embryo when he or she dies in utero.

Obviously, this is a big, big problem….I mean, could the Devil be any happier?  Catholic hospitals allowing abortions?  If Catholic hospitals continue to allow this, given this overwhelming evidence, are they still Catholic?

Originally published on February 24, 2015.