Benefit/risk profile of the combined pill

The combined pills available today with a combination of estrogen and progestin are well tolerated by the majority of women. However, taking the Pill can also lead to side effects. The most common side effects (e.g. headaches, intermenstrual bleeding, weight increase, breast tenderness or, in rare cases, venous thrombosis/ thromboembolism) have been known for a long time. Many of these potential side effects have been significantly reduced over the years by lowering the dose of estrogen. Venous thromboses which are not treated can in rare cases, also lead to pulmonary embolism (thromboembolism). This is a potentially life-threatening situation in which blood vessels in the lungs become clogged.

This rare event can occur in connection with all estrogen-progestin combined preparations, in other words, with all combined hormonal contraceptives (e.g. combined pill, vaginal ring, patch, injection). However, the risk of suffering from a venous thrombosis/thromboembolism while taking the contraceptive pill is considerably lower than, for example, during pregnancy or following childbirth.

• Out of 10,000 women of childbearing age who do not use a combined contraceptive pill, three to 4.5 suffer from venous thrombosis/thromboembolism per year (Dinger et al., in: Contraception 2007).
• Out of 10,000 women who take a combined contraceptive pill, eight to ten suffer from venous thrombosis/thromboembolism per year (Dinger et al., in: Contraception 2007).
• The risk is higher, however, for women during pregnancy and in the weeks following childbirth. Studies have determined that in this case between 20 and 30 out of 10,000 women suffer from venous thrombosis/thromboembolism (John A. Heit, in: Annals of Internal Medicine 2005).

A woman's individual risk of thrombosis is determined by personal factors. These include a genetic predisposition to thrombosis, overweight, and advanced age, among others. If such risk factors are known to be present, a woman should definitely discuss them with her physician before a contraceptive is prescribed. The physician can then assess which is the most suitable method of contraception.