RRM Academy Synopsis
Contraceptives let some embryos form and may end them, AAPLOG says
A 2020 physician committee opinion says all birth control methods fail at some rate, so embryos form during use. It also says several methods can work after fertilization. The committee reviewed studies of pills, implants, shots, IUDs and emergency contraception.
Key Findings
- In a 2010 study the committee cites, women taking the pill daily had an "ovulation" rate of 2.7%, women who missed pills 38.5%, and women using no pill 66.7%.
- An ESHRE review of progestin-only pills reports that 10% to a maximum of 15% of users had full suppression and around 50% had regular ovulatory cycles.
- The committee says the Hoogland scoring system was built to predict contraceptive failure. Pregnancies have occurred in women whose cycles failed its ovulation test.
- The IUD pregnancy rate of 0.1% shows that embryos can form during use. The committee concludes that IUDs act after fertilization and cause embryo death.
- In the first of two phase 3 ulipristal trials, miscarriage ended 5 of 6 pregnancies with known outcomes among women who kept the pregnancy. The second reported 4 of 6 miscarrying.
Interpretation
The document is a committee opinion, a narrative review written by an ethics committee of AAPLOG. The committee picks published studies, quotes several at length and draws its own conclusions about how each method works. The women covered use hormonal methods, IUDs or emergency contraception. The authors offer the review as an aid to informed consent. They note that no direct studies of miscarriage rates exist for progestin-only methods. Claims of action after fertilization are the committee's reading of that research.
RRM Context
RRM works with the body's own cycle. The opinion says progesterone-dependent tubal movement carries the embryo to the uterus during the Window of Implantation. It says progestin contraceptives can throw that timing off. The committee adds that many pro-life providers point to the benefits of fertility awareness for couples who choose it.
Abstract
The mechanism of action of contraceptive drugs and devices forms an essential part of informed consent for patients considering various methods of family planning. Currently the literature is confusing at best, in part due to non-uniform definitions of basic terms, as well as the misinterpretation of endpoints of current. AAPLOG members take different positions on the issue of contraception per se. The purpose of this document is to investigate and summarize the current evidence-based concerns regarding potential embryocidal mechanisms of action of modern contraceptive drugs and devices. There are three reasons for concern about embryos conceived during the use of a particular contraceptive drug or device:
- All contraceptive drugs and devices “fail” at a certain rate. As noted in a recent paper, “Unintended pregnancies occur with all contraceptive methods, including IUDs. This provides incontrovertible evidence that fertilization and implantation can occur, albeit rarely, with modern methods of contraception.”1
- Since pregnancies can and do occur during the use of all contraceptive drugs and devices, then we know by definition that fertilization, which marks the beginning of an embryonic human organism, can and does happen with all contraceptive drugs and devices since by definition, an embryo must be created for pregnancy to occur. That means embryos are created at a certain rate with all contraceptive drugs or devices.
- The contraceptive drug or device will create a certain environment for the embryos created during their use. This environment may adversely affect embryo survival up to the point of yielding a positive pregnancy test at the end of the cycle (the contraceptive efficacy end point). The remainder of this article will try to summarize what is known in the published medical literature about the environment facing an embryo who has been created during the use of various kinds of contraceptive drugs or devices.
