Hormonals and hypertension. (Clinical Challenges).

A 34-year-old woman who delivered her second baby nine weeks ago comes to the family planning clinic wishing to delay the birth of a third child. She experienced severe preeclampsia during her pregnancy, and her blood pressure now is 165/115 mm Hg. This elevated pressure was confirmed by measurements repeated several weeks apart. She used an intrauterine device (IUD) in the past but discontinued it because it increased her menstrual bleeding. She thinks diaphragms and spermicides are messy, and her husband dislikes condoms. Can she use hormonal contraceptives?

Evidence is growing that, among women with a history of hypertension, combined oral contraceptive (COC) users have a higher risk of adverse cardiovascular events, such as stroke and heart attack, than non-users. (9) As blood pressure increases, this risk increases. Because this client's blood pressure is quite elevated (exceeding 160/100 mm Hg), she should not use COCs or combined injectable contraceptives, according to the World Health Organization's medical eligibility criteria. The use of the progestin-only injectable depot-medroxyprogesterone acetate (DMPA) is not usually recommended, but progestinonly pills and subdermal implants can generally be used. For women with multiple risk factors for arterial cardiovascular disease--such as hypertension (blood pressure that exceeds 140/90 mm Hg), smoking, older age, history of cardiovascular disease, and diabetes--the same recommendations described above generally apply. (10)

Blood pressure measurements should be taken, if possible, before initiating the use of combined hormonal methods. The benefit of doing so has been demonstrated in various studies, including a World Health Organization collaborative, multicenter study involving users of low-dose COCs in developed and developing countries. In these studies, risks of ischemic stroke and heart attack were higher among women who did not have their blood pressure checked before starting COCs (a measure that would have screened out women with hypertension), compared with women who had their blood pressure checked. (11) However, if blood pressure cannot be measured, women should not be denied use of hormonal methods. This is because the absolute risk of any adverse cardiovascular events in women of reproductive age is low; even among hypertensive women ages 20 to 24 years who use COCs, such adverse events are estimated to be only 312 per million woman-years. (12) That risk is less than the risk associated with pregnancy and childbirth resulting from non-use of contraception, particularly in many resource-constrained settings.

Of note, however, this woman's blood pressure is dangerously high, meriting prompt evaluation and treatment.

(9.) World Health Organization. Cardiovascular Disease and Steroid Hormone Contraception: Report of a WHO Scientific Group. WHO Technical Report Series 877. Geneva, Switzerland: World Health Organization, 1998.

(10.) World Health Organization. Improving Access to Quality Care in Family Planning.

(11.) Heinemann LA, Lewis MA, Spitzer WO, et al. Thromboembolic stroke in young women. Contraception 1998;57(1):29-37; Dunn N, Thorogood M, Faragher B, et al. Oral contraceptives and myocardial infarction: results of the MICA case-control study. BMJ 1999;318 (7198): 1579-84; WHO Collaborative Study of Cardiovascular Disease and Steroid Hormone Contraception. Ischaemic stroke and combined oral contraceptives: results of an international, multicentre, case-control study. Lancet 1996;348(9026):498-505.

(12.) Farley TM, Collins J, Schlesselman JJ. Hormonal contraception and risk of cardiovascular disease. Contraception 1998;57(3):211-30.