Preconception advice for women with chronic hypertension

Pre-pregnancy advice in chronic hypertension:

Offer women with chronic hypertension referral to a specialist in hypertensive disorders of pregnancy to discuss the risks and benefits of treatment

angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers[2] (ARBs):

• there is an increased risk of congenital abnormalities if these drugs are taken during pregnancy
• discuss alternative antihypertensive treatment with the healthcare professional responsible for managing their hypertension, if they are planning pregnancy
• clinician should discuss with the women alternative treatment for managing their condition, if ACE inhibitors or ARBs are being taken for other conditions such as renal disease
• stop antihypertensive treatment in women taking ACE inhibitors or ARBs if they become pregnant (preferably within 2 working days of notification of pregnancy) and offer alternatives

thiazide or thiazide-like diuretics:

• may be an increased risk of congenital abnormalities and neonatal complications if these drugs are taken during pregnancy
• clinician should discuss with the women alternative antihypertensive treatment for managing their hypertension, if they are planning pregnancy

Advise women who take antihypertensive treatments other than ACE inhibitors, ARBs, thiazide or thiazide-like diuretics that the limited evidence available has not shown an increased risk of congenital malformation with such treatments

Continue with existing antihypertensive treatment if safe in pregnancy, or switch to an alternative treatment, unless:

• sustained systolic blood pressure is less than 110mmHg or
• sustained diastolic blood pressure is less than 70mmHg or
• the woman has symptomatic hypotension.

Offer antihypertensive treatment to pregnant women who have chronic hypertension and who are not already on treatment if they have:

• sustained systolic blood pressure of 140mmHg or higher or
• sustained diastolic blood pressure of 90mmHg or higher

When using medicines to treat hypertension in pregnancy, aim for a target blood pressure of 135/85mmHg

Consider labetalol to treat chronic hypertension in pregnant women

• consider nifedipine for women in whom labetalol is not suitable, or methyldopa if both labetalol and nifedipine are not suitable
  • base the choice on any pre-existing treatment, side-effect profiles, risks (including fetal effects) and the woman's preference

Offer pregnant women with chronic hypertension aspirin 75-150 mg once daily from 12 weeks

Offer placental growth factor (PlGF)-based testing to help rule out preeclampsia between 20 weeks and up to 35 weeks of pregnancy, if women with chronic hypertension are suspected of developing pre-eclampsia. (See the NICE diagnostics guidance on PlGF-based testing to help diagnose suspected preeclampsia).

Reference:

• NICE (June 2019). Hypertension in pregnancy: diagnosis and management