I have a patient in her early 20s who continues to have breakthrough bleeding (BTB) while taking oral contraceptive pills (OCPs). She has changed pills at least two times with no improvement. Assuming negative Pap results, would you advise endometrial biopsy on this patient? — Betsy  Schrader, ARNP-BC, EdD, Stillwater, Okla.

BTB is one of the more common side effects of using OCPs. An endometrial biopsy is not necessary in this case. The clinician should (1) obtain a thorough history of the woman’s current bleeding pattern as well as her bleeding pattern prior to OCP use (e.g., ask if the bleeding is postcoital or if she has any other symptoms associated with the bleeding); (2) screen for sexually transmitted infections or other forms of vaginitis; (3) do a thorough pelvic exam looking for cervical polyps, cervicitis, or cervical ectropion, as well as a bimanual exam to feel for an enlarged uterus, which could indicate uterine fibroids; (4) rule out pregnancy; (5) ensure the patient is taking the pill consistently, as missing pills or being late on pills is one of the most common causes of BTB; and (6) ask if the woman smokes, as smoking cessation may improve cycle control.

Endometrial biopsies are a screening tool used to assess for endometrial hyperplasia (and ultimately endometrial carcinoma), a condition found almost solely in peri- and postmenopausal, overweight, and anovulatory women. Endometrial biopsies should be performed on postmenopausal women who have any vaginal bleeding, women age 35 years and older who have abnormal bleeding for more than three months prior to starting contraception, and women who have a history of prolonged anovulation and thus, unopposed estrogen stimulation (e.g., obese women with polycystic ovary syndrome [PCOS]).

OCPs actually decrease the risk of endometrial carcinoma by keeping the endometrium thin (the likely reason for much of the BTB in OCP users). Women who have PCOS and other unopposed estrogenic states are prescribed OCPs to protect their endometrium from the hyperplasia that would otherwise result from their anovulatory cycles.

Once other causes of her BTB are ruled out, offer the patient the following options: (1) change birth-control methods altogether; (2) switch to a pill containing norethindrone acetate (Aygestin) as opposed to levonorgestrel, as this may decrease the duration of her BTB; (3) try a seven-day course of 1.25 mg conjugated estrogen or 2 mg estradiol in addition to her OCP; or (4) continue her current method after being counseled that BTB is a common finding and that unscheduled bleeding may improve over time with consistent pill use. — Mary Newberry, CNM, MSN (169-2)