Pregnancy category C.
Although no teratogenic effects have been demonstrated in animals, labetalol hydrochloride should only be used during the first trimester of pregnancy if the potential benefit outweighs the potential risk.
Labetalol hydrochloride crosses the placental barrier and the possibility of the consequences of alpha-and beta-adrenoceptor blockade in the fetus and neonate should be borne in mind. Perinatal and neonatal distress (bradycardia, hypotension, respiratory depression, hypoglycemia, hypothermia) has been rarely reported. Sometimes these symptoms have developed a day or two after birth. Response to supportive measures (e.g. intravenous fluids and glucose) is usually prompt but with severe preeclampsia. This may be related to diminish liver metabolism in premature babies.
Beta-blockers reduce placental perfusion, which may result in intrauterine fetal death, immature and premature deliveries. There is an increased risk of cardiac and pulmonary complications in the neonate in the postnatal period. Intrauterine and neonatal deaths have been reported with labetalol hydrochloride but other drugs (e.g. vasodilators, respiratory depressants) and the effects of preeclampsia, intrauterine growth retardation and prematurity were implicated. Such clinical experience warns against unduly prolonging high dose labetalol hydrochloride and delaying delivery and against coadministration of hydralazine.
Labetalol hydrochloride is excreted in breast milk. Breastfeeding is therefore not recommended.