Common Birth Control Pill Myths

Many women take combined oral contraceptives, otherwise known as "the pill" for birth control or to help with other gynecologic problems.  I wanted to dispel some of the long-standing myths about birth control pills.  I have patients come in frequently who don't want to take the pill because of what they've heard might happen to their fertility, risk of cancer, etc...

Myth #1 "I don't want to take the pill because I'm afraid I won't be able to get pregnant later"

Past use of combined oral contraceptives (the most common type prescribed, containing both estrogen and progestins) has not been linked to infertility.  In a study published in 2002, fertility rates after discontinuing birth control pills were 75% within 6 months, and 90% within 12 months (about 5% HIGHER than for those women not previously on pills).  This is similar to the overall pregnancy rate without contraceptives.  Sometimes, taking the pill can control other diseases, such as polycystic ovarian syndrome or endometriosis, which can impair fertility.  This can make it easier to get pregnant when the pill is discontinued.

Myth #2 "I'm worried that taking the pill will cause me to get cancer"

Combined oral contraceptives are not associated with an overall increased risk of cancer.  In fact, birth control pills have been shown in multiple studies to decrease the risk of ovarian, uterine, and colorectal cancer.  There have been no findings of increased risk of breast cancer among former pill users in multiple population-based studies.  Even among women with breast cancer in their family, or who have known genetic mutations making them susceptible to breast cancer, the pill is considered not to increase risk.  The pill is not recommend, however, in women with a personal history of breast cancer. 

Myth #3 "I'm worried that the pill will cause me to gain weight"

This is probably the most common concern I hear in my office.  There is little evidence, though, for a significant weight gain after starting the pill.  On average in one study, women gained about 0.5 kg (about a pound).

Myth #4 "Antibiotics reduce the effectiveness of the pill"

There is only one antibiotic that has been shown to decrease the pill's effectiveness - rifampin.  Rifampin is an antibiotic used very rarely, usually to treat infections like tuberculosis.  The most commonly prescribed antibiotics, such as penicillins, sulfa drugs, cephalosporins, fluoroquinolones, have no effect on hormone levels and do not decrease the pill's effectiveness.  There is no need to worry about using back-up methods of contraception unless you are taking rifampin.

Combined oral contraceptives have many benefits and risks, but overall are a safe and effective form of birth control as well as an effective treatment for many other gynecologic conditions.