All Vaginal Bleeding After Cessation of Long-term Oral Contraceptive Use May Not Be Menstruation

A May 8, 2006 Reuters article by Megan Rauscher, reporting on a study presented at the ACOG [American College of Obstetricians and Gynecologists] Annual Meeting by Anne R. Davis, MD, Assistant Professor of Clinical Obstetrics and Gynecology at Columbia University Medical Center, New York, NY, implies that there is no delay in return of menses after continuous-use OCs [oral contraceptives]. Although it is obvious that women who became pregnant had a return to fertility, it is inaccurate to assume that return of bleeding is “menstruation.” In fact, there are at least 4 types of bleeding: true menstruation, which follows 11-16 days after ovulation; implantation bleeding in early pregnancy; withdrawal bleeding, which is associated with anovulatory ovarian hormone activity or exogenous hormone therapy, including contraceptives; and pathologic or “contact” bleeding.

Although not wishing to be pedantic, and with all due respect to Dr. Davis, it is nonetheless time to be more exact. The physiology of the menstrual cycle is now well understood. Ovulation is the sentinel event of the cycle. To describe bleeding intervals as “cycles” hearkens back to the calendar rhythm model.

“Correlating the Signs and Symptoms of Fertility at the Vulva and Vagina” and “The Continuum” (www.woomb.org) are concise presentations of the cumulative work of Drs. John and Lyn Billings; James B. Brown, PhD; and Erik Odeblad, MD, PhD, over the past 50 years illustrating that the cervix and vagina are a perfect barometer of ovarian activity. Roughly 1 million hormonal assays collected by women throughout reproductive life have been analyzed and reported by the Ovulation Method Resource and Research Council. A changing pattern of discharge is a biochemical marker of fertility. A nonchanging pattern has diagnostic implications.

I would challenge my clinical colleagues to stop asking the historical question of “last menstrual period” in favor of “last ovulation,” and offer to collaborate on a scientific study that demonstrates true return of fertility after discontinuing continuous-use OCs.

Readers are encouraged to respond to George Lundberg, MD, Editor of MedGenMed, for the editor's eyes only or for possible publication via email: glundberg@medscape.net