Maternal severe migraine and risk of congenital limb deficiencies.

BACKGROUND

Migraines occurs frequently during pregnancy; however, there are no published data on their possible teratogenic potential in a controlled epidemiological study. Therefore, we examined the risk of congenital abnormalities in infants born to women who had migraines and other headaches during pregnancy.

METHODS

Between 1980 and 1996, the Hungarian Case-Control Surveillance of Congenital Abnormalities evaluated 22,843 cases (newborns or fetuses) with congenital abnormalities, 38,151 control newborn infants without any abnormalities, and 834 malformed controls with Down syndrome.

RESULTS

Migraines anytime during pregnancy occurred in 565 (2.5%) mothers of the case group compared with 713 (1.9%) mothers in the control group (crude prevalence odds ratio [POR], 1.3; 95% confidence interval [CI], 1.2-1.5) and 24 (2.9%) pregnant women in the malformed control group (crude POR, 0.9; 95% CI, 0.6-1.3) The mothers of 247 cases, 533 controls, and 21 malformed controls had severe migraines during the second and/or third months of pregnancy. There was only 1 congenital abnormality group: limb deficiencies, which had a higher rate of maternal migraines during the second and third months of pregnancy both at the comparison of cases and matched controls (adjusted POR, 2.5; 95% CI, 1.1-5.8) and of cases and malformed controls (adjusted POR, 1.7; 95% CI, 1.3-3.0). There was no association between other headaches and different congenital abnormalities at the comparison of cases and controls.

CONCLUSIONS

Our data showed that maternal severe migraines during the second and/or third months of pregnancy were associated with an increased risk of congenital limb deficiencies. A similar association was not detected between congenital anomalies and other headaches during pregnancy. Our study was not based on a prior hypothesis; therefore, these data can be considered only as a signal that needs confirmation by independent data sets.