Contraception in Women with Heart Disease

Heart disease is now the leading cause of death during pregnancy in developed countries. This trend is likely the result of advances in medical care for women with pre-existing heart diseases at birth, with many now reaching puberty and childbearing age. Rising maternal age also means more pregnancies during the late reproductive years, which are associated with higher risks of heart conditions.

Pregnancies will be high risk in some of these women, and they will benefit from preconception evaluation and advice. Effective and safe contraception is crucial in women with contraindications for pregnancy. They are women with

• severe heart failure
• severe mitral stenosis
• symptomatic severe aortic stenosis
• severe pulmonary hypertension
• severe aorta dilatation (in conditions such as Marfan’s syndrome)
• history of pregnancy-induced heart failure with residual heart dysfunction.

Termination of pregnancy should be discussed if it occurs in women with these heart conditions, putting them at high risks of complications and death during pregnancy.

Women with heart disease may also be taking medications that could cause birth or developmental defects in fetuses. Effective contraception is, therefore, necessary to minimise the adverse effects of fetal outcomes.

Contraceptive methods and their risks involved

Women with heart disease should consider contraceptive efficacy, cardiovascular safety and individuals’ preference when choosing contraception. The issues may be complex for some and will require the input of both a cardiologist and an obstetrician to identify the optimal approach.

Barrier contraception

Forms: Condoms, diaphragms, cervical caps, calendar method, withdrawal before ejaculation

Not ideal for women (with high risks heart conditions) who must avoid pregnancy. However, there are no cardiac risks and contraindications to any barrier methods.

Combined estrogens and progesterone contraceptives

Forms: Tablets with regular stop periods, vaginal ring, injection, transdermal patch

Efficacy is high, but the oestrogen component in combined oral contraceptives significantly increases the risk of venous thrombosis (blood clot in veins) by 2- to 7-fold, and increases the risk of arterial thrombosis and hypertension. Therefore, combined oral contraceptives are not recommended or even contraindicated in women with heart disease (especially those with an increased venous or arterial thrombotic risk), ischaemic heart disease or hypertension.

Progestogen-only contraceptive

Forms: oral pills, injection, subdermal implants

In general, progesterone-only contraceptives does not increase the risk of thrombosis significantly. Desogestrel containing progesterone-only pill has contraceptive efficacy and safety similar to the combined oral contraceptives. It is, therefore, the only progesterone-only pill recommended in women with (severe) cardiac disease.

Reversible intrauterine contraceptives

Forms: Copper-containing intrauterine device (copper-IUD), Levonogestrel-releasing intrauterine system (IUS)

These are considered long-acting reversible contraceptives. By eliminating the dependency on patient adherence, their efficacy is excellent even exceeding sterilisation and fertility rapidly returns upon removal. An intrauterine device does not affect thrombogenic risk.

Sterilisation

Forms: Procedures including laparoscopic or open tubal ligation and hysteroscopic insertion of intratubal stents

These procedures are considered irreversible and may have a significant psychological impact on women. They also have failure rates – although rare – and carry risks of ectopic pregnancy, which places women with heart disease at high risk.

Contraception advice for women with specific heart conditions

Heart failure

Pregnancy in women previously diagnosed with compromised heart function carries a risk of heart failure and occasionally death during pregnancy. Deterioration of heart function is reported in up to 50% of cases in the peripartum period, despite optimal medical therapy.

Pregnancy is high risk and contraindicated in women with severely compromised heart function, and effective contraception is crucial. Choice of contraceptive method should consider the risk of thrombosis, the use of anticoagulation agents, and the occurrence of arrhythmias. However, combined oral contraceptives are contraindicated in women with heart failure, especially when other risk factors, such as smoking and hypertension, are present.

Heart disease requiring anticoagulation

Women with mechanical valves, certain congenital heart diseases, and conditions causing elevated lung pressure, have an increased risk of thrombosis, which is commonly managed with anticoagulation. In these women, the cardiovascular and thrombogenic danger of (unplanned) pregnancy often outweighs the inherent risks of most contraceptive methods.

Women taking anticoagulants will need a reliable contraceptive method without increased thrombotic risk, which reduce menstrual blood loss and inhibits ovulation. Progesterone-only methods, and especially the reversible intrauterine contraceptives are therefore the method of choice in these women.

Combined oral contraceptives are generally not recommended for use in this group of patients, as there is no good evidence on whether the increased thrombogenic risks of this contraception method is controlled by anticoagulation.

Arrhythmia

Women with arrhythmia often use medication that increases the risks of birth or developmental defects in the fetus. The use of combined oral contraceptives should be avoided in patients with arrhythmia as there will be an increased risk of thromboembolism such as in atrial fibrillation and atrial flutter.

Points to note:

• The number of women of childbearing age with congenital or acquired heart disease is increasing. There are risks of heart complications and mortality in these women during pregnancy, and contraception is an essential part of their care.
• Contraceptive counselling should begin early. The choice of contraceptive method should be based on the underlying cardiovascular risk of an unplanned pregnancy, the risks and benefits of the contraceptive option and individual’s preferences and acceptability.
• As good quality studies are absent in guiding contraception in women with heart disease, the management approach is based on expert opinion. In complex cases when ambiguity arises, input from both a cardiologist and an individualised contraception approach to optimise risks in this group of patients.

Article is contributed by Dr Chan Wan Xian, Committee Member of the Editorial Committee and Go Red for Women Committee at Singapore Heart Foundation; and Senior Consultant Cardiologist at the Asian Heart and Vascular Centre.