In fact, it is more likely that pregnancy will worsen some medical problems, making safe, effective contraception imperative. The proven reliability of oral contraception allows women diagnosed with serious conditions such as diabetes or renal disease to plan conception and not be faced with a surprise pregnancy. In addition, decreased menstrual flow resulting from the use of OCs may make oral contraception the treatment of choice for women with chronic bleeding disorders. Such contraindications would include a history of deep vein thrombosis or other embolic event, diagnosis of coronary artery disease, or acute immobilization such as orthopedic surgery. When using hormonal agents in women with medical disorders, health care professionals need to exercise balanced, reasoned judgment.
Anecdotal cases provide support for the belief that OCs worsen some medical conditions.
The adverse effect in each case is most likely due to inadequate adjustment of systemic medications when OCs are used. Clinicians must be aware that changes in serum proteins caused by oral contraception may lead to lower circulating blood levels of several important medications. Another myth is that oral contraception causes or worsens hypertension. This myth persists despite evidence to the contrary. There are occasional reports that some women experience an increase in blood pressure after commencing use of OCs.