A nationwide population-based register study of neonatal outcomes in pregnancy-associated Bell's palsy

For unclear reasons, Bell's palsy is more common during pregnancy and puerperium. This study assesses neonatal outcomes related to Bell's palsy in these periods.

A Swedish nationwide register-based cohort study 2005-2015. Women with Bell's palsy were identified in the National Patient Register, and women giving birth in the Medical Birth Register. By merging these data, women with Bell's palsy during pregnancy or puerperium (two months postpartum) were identified. Women without Bell's palsy history served as comparison. Multivariable logistic regression identified risk factors, with adjusted odds ratios (aOR) and 95% confidence intervals (CI).

A total of 2 051 women with pregnancy-associated Bell's palsy were identified, 1 191 in pregnancy and 860 during puerperium. As a comparison group, 1188 849 women without Bell's palsy giving birth during the same years were included. Bell's palsy during pregnancy was not associated with adverse neonatal outcomes. Adverse neonatal outcomes were associated with Bell's palsy in puerperium (aOR 1.27, 95% CI 1.06-1.52). Additional risk factors for Bell's palsy in puerperium included country of origin Africa (aOR 2.00, 95% CI 1.53-2.63) or South America (aOR 2.05, 95% CI 1.28-3.28), multiple pregnancy (aOR 2.27 (95% CI 1.70-3.02), preeclampsia (aOR 2.54, 95% CI 2.02-3.21), infection labor (aOR 1.39, 95% CI 1.07-1.82), and epidural/spinal (aOR 1.18, 95% CI 1.02-1.37).

Adverse neonatal outcomes were more common in women with Bell's palsy in puerperium but not among women with Bell's palsy in pregnancy, suggesting that adverse outcomes at childbirth may trigger Bell's palsy in puerperium.