“The Pill” has been one of the greatest innovations in women’s health.  Developed in the 1960’s, oral contraceptives, also known as birth control pills, have given new freedom to women in family planning.  Today, about 12 million women in the US, and over 100 million women worldwide, are on the pill.

Birth control pills contain two synthetic hormones – estrogen and progestin.  Some people used to say that birth control pills worked by tricking your body into thinking it was pregnant.  In some ways, this is true.  When you are pregnant, you produce extremely high amounts of these two hormones.  When the levels are high, the hormones in the brain responsible for triggering egg release, or ovulation, are suppressed.  Similarly, when the pill is taken daily, a constant level of estrogen and progesterone is achieved, and ovulation stops.

If the pill is taken correctly, the chance of getting pregnant is 0.3% per year.  However, if pills are missed, the pregnancy rate increases to 7%.

Despite its wide usage and years of research dating back to its first approval as a contraceptive over 50 years ago, there are still many common myths surrounding the pill.

  1. The pill causes weight gain.  Many studies have proven that women who are on the pill do not gain more weight than women not on the pill.  While some pills may cause water retention, this only accounts for 1-2 pounds of weight gain.
  2. Birth control pills cause cancer.  There is no link between birth control pills and cancer.  In fact, some studies have shown that cancer of the uterus, colon, and ovary is decreased in women who take the pill for more than 10 years.  A recent study in the British Medical Journal followed over 46,000 women and found that the chance of getting any type of cancer was 10% less if the woman had ever taken birth control pills during her lifetime.
  3. Being on the pill will make it harder to get pregnant in the future.  Actually, birth control pills do not affect fertility. The hormones in birth control pills are metabolized in your body quickly; that is why they must be taken every day.  Once the hormones are out of the system, within 2 days, the process of egg growth will resume.  The first ovulation usually occurs within 2-6 weeks.  For some women who have been on the pill for more than a year, ovulation may not resume until 3 months have past. When a woman has been on the pill for many years and then decides to get pregnant, she may find that her fertility rate is lower simply because she is older, not because of the previous pill use.
  4. Birth control pills will make me feel crazy.  Mood changes are the result of a complex interaction of brain hormones and external factors.  For this reason, it can be difficult to determine the true cause of these swings.  The mood changes associated with PMS (Premenstrual Syndrome) are actually eliminated by taking the pill.  Those changes are associated with the ovary’s production of progesterone after ovulation.  When taking the pills ovulation is stopped, and therefore progesterone is not made.  That being said, some women insist that their moods become more irritable, erratic, and depressed.  While we don’t have a clear physiologic reason for this problem, it is a rare side effect of the pill.
  5. You should take a break from the pill to clean it out of your system.  There is no medical reason that you need to stop taking the birth control pill.  In fact, long-term users of oral contraceptives also benefit from lighter and less painful periods, predicable cycles, and less acne.
  6. If you get pregnant on the pill, there is a higher chance of miscarriage or birth defects.  Occasionally, a woman will miss a few pills, then restart them and unknowingly conceive.  She then continues on her pills while she is pregnant.  While this is not recommended, there is no increased risk of miscarriage or birth defects in these pregnancies.

Birth control pills should not be taken if you have a history of blood clots, uncontrolled high blood pressure,  migraine headaches with aura, or if you are over 35 years old and smoke.  The goal of any birth control pill is to prevent pregnancy in the safest, most effective way with the least side effects.  For most women, once they understand that these concerns are only myths, the pill is an excellent choice.