Polycystic Ovary Syndrome (PCOS): is a hormonal imbalance which causes irregular menstrual periods, acne, and excess hair growth. Birth control pills work by lowering certain hormone levels to regulate menstrual periods. When hormone levels are decreased to normal, acne and hair growth often improve.
Endometriosis: Most girls with endometriosis have cramps or pelvic pain during their menstrual cycle. Birth control pills are often prescribed continuously to treat endometriosis and work by temporarily preventing periods. Since periods can cause pain for young women with endometriosis, stopping periods will usually improve cramps and pelvic pain.
Lack of periods (“amenorrhea”) from low weight, stress, excessive exercise, or damage to the ovaries from radiation or chemotherapy: With any of these conditions, the hormone “estrogen” is not made in normal amounts by the body. Birth control pills may be prescribed to replace estrogen, which helps to regulate the menstrual cycle. For girls whose menstrual periods are irregular (too few - or not at all), birth control pills can help to regulate the menstrual cycle to every 28 days and provide the body with normal amounts of estrogen. Normal estrogen levels are important for healthy bones.
Menstrual Cramps: When over-the-counter medications don't help with severe cramps, birth control pills may be the solution because they prevent ovulation and lighten periods.
Premenstrual Syndrome (PMS): Symptoms of PMS such as mood swings, breast soreness, and bloating, along with acne can occur up to 2 weeks before a young women's period. Birth control pills may be prescribed to stop ovulation and keep hormone levels balanced. Symptoms may improve, particularly when oral contraceptive pills are prescribed continuously.
Heavy Menstrual Periods: Birth control pills can reduce the amount and length of menstrual bleeding.
Acne: For moderate to severe acne, which over-the-counter and prescription medications haven't cured, birth control pills may be prescribed. The hormones in the Pill can help stop acne from forming. Be patient though, since it takes several months for birth control pills to work.
Other Medical Benefits
Because there is less menstrual bleeding when taking birth control pills, you are less likely to get anemia (low number of red blood cells, which carry oxygen from the lungs to the tissues). Birth control pills also lower your chance of getting endometrial (lining of the uterus) cancer, ovarian cancer, and ovarian cysts.