• Acitretin, adapalene, alitretinoin, isotretinoin and tretinoin are retinoids used mainly in dermatology. Effective contraception is indispensable throughout the period when any of these drugs is taken and after the retinoid is stopped, for one month after last taking isotretinoin, and, as a precautionary measure, up to 3 years after taking acitretin.
• Ribavirin is an antiviral used in hepatitis C. Male patients taking ribavirin should always use a condom in case of heterosexual intercourse, and should encourage their female partners to use effective contraception. It is important that female patients taking ribavirine use effective contraception.  
• Vitamine K antagonists such as acenocoumarol, warfarin and fluindione can cause birth defects and fetal haemorrhage. In case of pregnancy, it is better, if possible, to substitute a low-molecular weight heparin instead.  
• Misoprostol is used for prevention of gastroduodenal ulcers, and as an abortion drug in combination with mifepristone. It should not be used in patients who are or might be pregnant.
• Valproic acid  is a first-line treatment for various kinds of epilepsy, but can expose the unborn child to serious adverse effects. When valproic acid is taken by a woman who might become pregnant, effective contraception should be ensured. When a pregnancy is planned, a better alternative should be considered.
• Angiotensin Converting Enzyme (ACE) inhibitors, angiotensin II receptor blockers (alias sartans), or aliskiren can expose the fetus to serious and possibly fatal complications. If these drugs are considered in a woman who might become pregnant, it is necessary to watch carefully for pregnancy. If a pregnant woman has been exposed to any of these drugs, it is important to withdraw the drug as soon as possible and to monitor renal function in the fetus.

©Prescrire 1 August 2013

Source: "Femmes enceintes et médicaments" Rev Prescrire 2013 ; 33 (358).