Are you considering birth control pills as your contraceptive method? Understanding their side effects is crucial. Let's dive into the common side effects of combination and progesterone-only pills.
Combination birth control pills contain both estrogen and progesterone, and are the type of birth control pills that people typically refer to when they just say “birth control pills.”
Typically, combination birth control pills give you your period once a month, but these tend to be lighter and shorter than most unmedicated periods. Sometimes, especially with prolonged use, the period may go away altogether. This is not harmful.
The opposite may also happen, when unscheduled bleeding occurs when it is not time for the period - this is typically not harmful, but probably indicates you need a higher dose of estrogen in your birth control pill. The birth control pill pack may also be manipulated so that the user does not get periods at all, or only every three months, by skipping the “placebo week.”
Unlike birth control methods that do not contain estrogen, combination birth control pills may have some serious side effects. Specifically, high doses of estrogen, especially in combination with other risk factors, can cause blood clots, which may be in the veins in the legs, or in serious situations, in the lungs, the heart, or the brain, and cause a heart attack, stroke, or pulmonary embolism. For this reason, combination birth control pills should only be used in carefully selected low risk patients. Other common bothersome side effects of combination birth control pills may include nausea, headaches, or breast tenderness, but these tend to resolve with ongoing use.
Classically, the “progesterone only birth control pill”refers to birth control pills that contain 0.35 mg of norethindrone (Heather, etc).
Since these do not stop ovulation but rather work by thickening the cervical mucus to prevent sperm from passing through, they are associated with a higher risk of unscheduled bleeding (and failure!) compared to combined birth control pills. Furthermore, there are no placebo pills and so they would not help to regulate periods to be monthly.
Recently, there has been release of a newer type of progesterone-only birth control pill, which contains 4 mg drospirenone (Slynd). These do stop ovulation and do contain placebo pills, and so would have a similar bleeding side effect profile as combination birth control pills. Since these do not contain estrogen, which is the main cause of the serious as well as bothersome side effects of combined birth control pills, they tend to be safer as well as better tolerated than combined birth control pills.
