In some eyes, Implanon is an abortifacient


“Everything you need to know about the contraceptive implant” by Philip D. Darney, MD, MSc

I find Dr. Darney’s article misleading when it comes to the “2 mechanisms” of action given for Implanon. Inhibition of ovulation and failure of sperm penetration through cervical mucus are discussed, and readers are assured that the device “lacks abortifacient properties.” This assertion contradicts both the physician package insert and the patient information published by Organon and available on its Web site at These resources clearly state that “alterations in the endometrium” are an additional mechanism of action, ie, that Implanon could cause failure of blastocyst implantation.

Although some organizations do not consider the loss of a preimplantation embryo to be an “abortion,” it is erroneous to think that every patient will believe so. Indeed, some may pause at the thought that their chosen method of birth control may be causing the loss of early embryos.

Patients and providers deserve to know these facts, and we should be forthcoming about disclosing them. For an excellent review of this subject, please see Larimore’s article, “Postfertilization effects of oral contraceptives and their relationship to informed consent” (Arch Fam Med. 2000;9:126–133).

Kyle Beiter, MD
Phoenix, Ariz

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