What can be the adverse effects of oral contraceptives? Although oral contraceptives can have some adverse effects, the overall risk of them occurring is small. Oral contraceptives can cause breakthrough bleeding (which may subside over time or when the dose of estrogen is increased) or lead to amenorrhea. It may subside if the progestin dose is reduced. In some women, ovulation remains suppressed for several months after they stop taking birth control pills, but this has no long-term effect on fertility. Contraceptives do not adversely affect pregnancy outcome when conception occurs during or after their use. Estrogens increase aldosterone production and cause sodium retention, which can cause reversible increases in blood pressure and weight. Weight gain may be accompanied by abdominal swelling and edema. Most progestins used in contraceptives are related to 19-nortestosterone and are androgenic. Androgenic effects can include acne, nervousness, and an anabolic effect leading to weight gain. The incidence of deep vein thrombosis and thromboembolism increases with increasing dose of estrogen. With oral contraceptives that contain 10 to 35 mcg of estrogen, the risk is 2 to 4 times greater than the risk before taking them. However, this increased risk is still much lower than the risk associated with pregnancy. The risk probably increases because the production of clotting factors in the liver and the adhesion of platelets increase. If deep vein thrombosis or pulmonary embolism is suspected in a woman taking oral contraceptives, use should be stopped immediately. Also, contraceptives should be stopped at least one month before any major surgery that requires immobilization for a long time and should not be taken again for a month afterwards. Women with a family history of idiopathic venous thromboembolism or known thrombotic disease should not use contraceptives that contain estrogen. The effects of contraceptives on the central nervous system may include nausea, vomiting, headache, depression, and sleep disturbances. Although an increased risk of stroke has been attributed to the use of oral contraceptives, low-dose combined contraceptives do not increase the risk of stroke in healthy women. However, if focal neurological symptoms, aphasia, or other symptoms that may portend a stroke develop, the contraceptive should be stopped immediately. Smokers over the age of 35 should not use contraceptives that contain estrogen because of the increased risk of myocardial infarction and/or stroke. Serum cholesterol and “good cholesterol” (HDL) levels may decrease when high-dose progestin contraceptives are used, but usually increase when low-dose progestin and estrogen contraceptives are used.The estrogen in oral contraceptives, in turn, raises triglyceride levels and may exacerbate pre-existing hypertriglyceridemia. Oral contraceptives have some very important health benefits. High- and low-dose combined oral contraceptives reduce the risk of: Endometrial cancer by 60% after at least 10 years of use. Ovarian cancer by about 50% after 5 years of use and 80% after ≥ 10 years of use They also reduce the risk of functional ovarian cysts, benign ovarian tumors, abnormal uterine bleeding due to ovulatory dysfunction, dysmenorrhea, premenstrual dysphoric disorder, iron deficiency anemia and benign breast diseases. Salpingitis, which can negatively affect a woman’s fertility, occurs less frequently in women using oral contraceptives. Bibliography: Oral Contraceptives – Gynecology and Obstetrics – MSD Manual Professional Edition (msdmanuals.com)