What is the relationship between blood pressure checks and the use of oral contraceptives (OCPs)?

From the Guidelines

Blood pressure should be checked before starting oral contraceptives and monitored regularly during use, with the frequency of checks ranging from every 6 months to annually, depending on the individual's risk factors and medical history, as recommended by medical society guidelines 1.

Importance of Blood Pressure Monitoring

Blood pressure monitoring is crucial for individuals taking oral contraceptives, as these medications can increase the risk of hypertension and cardiovascular disease. The risk of hypertension is higher in women taking combined hormonal contraceptives (CHCs) compared to those taking progestin-only pills (POPs) 1.

Recommendations for Blood Pressure Checks

For women with normal blood pressure (below 120/80 mmHg), checking blood pressure at 3 months after starting oral contraceptives and then annually is recommended. Women with borderline hypertension (120-139/80-89 mmHg) should have their blood pressure checked more frequently, approximately every 3-6 months.

Oral Contraceptives and Blood Pressure Elevation

Oral contraceptives, particularly those containing estrogen, can cause blood pressure elevations in some women due to increased production of angiotensinogen in the liver, which activates the renin-angiotensin-aldosterone system. Combined hormonal contraceptives (containing estrogen and progestin) pose a greater risk for blood pressure elevation than progestin-only methods 1.

Management of Hypertension in Oral Contraceptive Users

If a woman develops hypertension while on combined oral contraceptives, switching to a progestin-only method like the mini-pill (norethindrone 0.35mg daily), depo-medroxyprogesterone acetate injections, or a levonorgestrel IUD may be appropriate. Women with pre-existing hypertension, especially if poorly controlled or with additional cardiovascular risk factors, should generally avoid estrogen-containing contraceptives and consider progestin-only or non-hormonal methods instead 1.

Newer Oral Contraceptives and Blood Pressure

Newer oral contraceptives, such as those containing drospirenone, have shown promise in mitigating the adverse effects of oral contraceptives on blood pressure. Drospirenone has anti-mineralocorticoid effects, which can help reduce blood pressure in some women 1.

Clinical Considerations

Healthcare providers should consider recommending women obtain blood pressure measurements in nonclinical settings, such as pharmacies or fire stations, to improve monitoring and management of blood pressure in oral contraceptive users 1.

From the FDA Drug Label

An increase in blood pressure has been reported in women taking oral contraceptives (68) and this increase is more likely in older oral contraceptive users (69) and with continued use (61) Data from the Royal College of General Practitioners (12) and subsequent randomized trials have shown that the incidence of hypertension increases with increasing quantities of progestogens. Women with a history of hypertension or hypertension-related diseases, or renal disease (70) should be encouraged to use another method of contraception If women elect to use oral contraceptives, they should be monitored closely and if significant elevation of blood pressure occurs, oral contraceptives should be discontinued. For most women, elevated blood pressure will return to normal after stopping oral contraceptives (69), and there is no difference in the occurrence of hypertension between ever- and never-users (68,70,71).

Blood Pressure Monitoring with Oral Contraceptives:

• Women taking oral contraceptives should have their blood pressure checked regularly.
• The risk of hypertension increases with the quantity of progestogens and duration of use.
• Women with a history of hypertension or related diseases should consider alternative contraception methods.
• If significant blood pressure elevation occurs, oral contraceptives should be discontinued 2, 2.

From the Research

Blood Pressure Effects of Oral Contraceptives

• Oral contraceptives can result in a mild elevation of blood pressure in most women and overt hypertension in about 5% of users 3.
• The risk of cardiovascular complications is found primarily in women over 35 years of age and in those who smoke 3.
• Preparations with an estrogen content of 30 g and a progestogen content of 1 mg or less appear to be safe 3.

Combined Oral Contraceptives and Hypertension

• Combined oral contraceptives are associated with increased cardiovascular risk, but contraceptives containing drospirenone may have a positive or neutral effect on neurohumoral activation and metabolic homeostasis of hypertensive women at reproductive age 4.
• A contraceptive containing 20 mcg of ethinyl estradiol and 3 mg of drospirenone causes no significant changes in clinical and autonomic parameters, metabolic variables, and neurohumoral axis of hypertensive women 4.

Cardiovascular Risks Associated with Oral Contraceptives

• Women with hypertension are at increased risk for cardiovascular events, and combined oral contraceptive use is associated with a small excess risk for cardiovascular events among healthy women 5.
• The use of combined oral contraceptives is associated with approximately 2-fold and over 4-fold increased relative risks of arterial and venous thromboembolic events, respectively 6.
• The risk of myocardial infarction does not correlate to the length of therapy and disappears after treatment termination 6.

Blood Pressure Measurement and Oral Contraceptive Use

• Women who did not have their blood pressure measured before initiating oral contraceptive use were at higher risk for ischemic stroke and acute myocardial infarction than oral contraceptive users who did not have their blood pressure measured 5.
• Women who had their blood pressure measured before oral contraceptive use have 2-2.5-fold decreased risk of myocardial infarction and ischemic stroke 6.