In 2001, the U.S. Centers for Disease Control and Prevention reported that as many as half of all U.S. pregnancies occurred accidentally---many to women using some form of contraceptive. To maximize the chances of a healthy pregnancy, the American College of Obstetricians and Gynecologists recommends that women discontinue pill use as soon as they confirm their pregnancy. Taking and relying upon the results of a home pregnancy test can allow women to diagnose their pregnancy and schedule an appointment with their doctor as early as possible.
Significance
The Mayo Clinic unequivocally states that birth control pills do not impact the accuracy of home pregnancy tests (HPTs)---so if you experience a positive result on the test, it is an indication of pregnancy. Call your doctor's office for guidance on discontinuing your pills and to schedule an exam.
Time Frame
When taken after you notice a missed period or other signs of pregnancy such as nausea or breast tenderness, pregnancy tests can detect a pregnancy even if you currently take birth control pills. According to the National Women's Health Information Center, most HPTs offer accurate results about a week after your missed period. Some women might obtain positive results earlier and others later, but most fall into this range.
Considerations
Pregnancy while taking birth control pills occurs in about 1 in 100 women---even with perfect use. According to Robert Barbieri, the chief of obstetrics at Brigham and Women's Hospital, the FDA approves the pills for a 99 percent success rate with good use, making a pregnancy while on birth control a possibility.
Misconceptions
False positives on HPTs because of medication use occurs very rarely. The only medications that might potentially affect home pregnancy test results are those containing the pregnancy hormone human chorionic gonadotropin such as Pregnyl, Profasi or APL. Antibiotics, birth control pills and most other medications do not interfere with your HPT results.
Prevention/Solution
Take your pills on a regular basis to minimize the chances of an unplanned pregnancy. If you miss a period or experience other signs of pregnancy such as nausea or vomiting, use an HPT to confirm the pregnancy. Although a positive result is a good indicator of pregnancy, a negative one might mean it is too early in the pregnancy for a positive result. Test again in a week if your period fails to appear. If you suspect pregnancy but keep getting a negative result, see your doctor.
