Antihypertensive treatment during pregnancy and functional development at primary school age in a historical cohort study

OBJECTIVE: To determine the functional development of children born after treatment of mild-to-moderate gestational hypertension with labetalol versus methyldopa, and no antihypertensive treatment. DESIGN: Historical cohort study. SETTING: Twelve Dutch hospital departments of obstetrics. POPULATION: Live-born children born in these hospitals and prenatally exposed to labetalol, methyldopa, or bed rest because of mild-to-moderate gestational hypertension. METHODS: Central nervous system development was measured with standard tests at 4-10 years of age. Linear regression techniques and Pearson's chi-square tests were used to compare the groups with regard to the outcome measures. MAIN OUTCOME MEASURES: Intelligence quotient (IQ), concentration, motor development, and behaviour at primary school age. RESULTS: A total of 202 children were included in the analyses. More children exposed to labetalol had attention deficit hyperactivity disorder (ADHD) than those exposed to methyldopa (OR 2.3; 95% CI 0.7-7.3), or those born to women who had been admitted for bed rest (OR 4.1; 95% CI 1.2-13.9). Sleeping problems seemed to be reported more frequently after prenatal methyldopa exposure than after exposure to labetalol (OR 3.2; 95% CI 0.6-16.7) or bed rest (OR 4.5; 95% CI 0.9-23.2), although the differences were not statistically significant. Test scores on other aspects of functional development did not differ between the three groups. CONCLUSIONS: In this hypothesis-generating study, labetalol exposure in utero seemed to increase the risk of ADHD among children of primary school age, whereas prenatal methyldopa exposure might influence sleep. Further studies with appropriate sample sizes are warranted to determine the long-term effects of antihypertensive medications.