EFFECTS OF PROPRANOLOL DURING PREGNANCY AND DEVELOPMENT OF RATS .1. ADVERSE-EFFECTS DURING PREGNANCY

Pregnant rats, treated with high doses of propranolol, gave birth to small for dates neonates. Litter size was affected in daily doses of 100 and 150 mg/kg/day. Propranolol markedly influenced the gain in weight normally observed in pregnant rats. The placentas of the rats which received the higher doses of propranolol weighed about 30% less than normal placentas. Speculation: Pregnant rats, treated with propranolol, gave birth to small for dates neonates. This effect is possibly the result of a drug-induced reduction in transport across cellular membranes, resulting in malnutrition. Since similar effects were reported in humans, treatment with propranolol during pregnancy should be further reevaluated in laboratory animals. © 1978 International Pediatric Research Foundation, Inc.