The most common side effects of the birth control pills include nausea, headache, breast tenderness, weight gain, irregular bleeding, and mood changes. These side effects often subside after a few months' use. Scanty menstrual periods or breakthrough bleeding may occur but are often temporary, and neither side effect is serious. Women with a history of migraines may notice an increase in migraine frequency. On the other hand, women whose migraines are triggered by fluctuations in their own hormone levels may notice improvement in migraines with oral contraceptive use because of the more uniform hormone levels during oral contraceptive use. Uncommonly, oral contraceptives may contribute to increased blood pressure, blood clots, heart attack, and stroke. Women who smoke, especially those over 35, and women with certain medical conditions, such as a history of blood clots or breast or endometrial cancer, may be advised against taking oral contraceptives, as these conditions can increase the adverse risks of oral contraceptives.
Oral contraceptives have been shown to drain your body of vitamin B6, B12, zinc, and blood magnesium levels. This can set a cascade of unwanted side effects in motion, including sleeplessness, mood swings, diarrhea, poor immune resistance, insomnia, depression — even anorexia.
Women with Breast Lumps and osteopenia/osteoporosis, should consult with their doctor before using birth control pills.
These pills should never be used just to regulate the monthly cycle due to all of the above side effects.
All natural birth control methods should be researched before considering birth control pills particularly for young women.
If you must take birth control pill regardless of the dose, women should take a good multivitamins/minerals supplements as well as an antioxidant to minimize the potential side effects.

Women who are taking birth control pills should do their monthly breast self exam as well as an annual ultrasound with their physician.
An annual bone density scan is also recommended to avoid premature osteoporosis.

Author's Bio: 

Dr. George Grant, Ph.D., I.M.D. Specialist in Nutrition, Stress & Biofeedback