Bell's palsy and tinnitus during pregnancy: Predictors of pre-eclampsia? Three cases and a detailed review of the literature

We present two cases of Bells palsy, and another with tinnitus, all in asso ciation with pre-eclampsia in the third trimester of pregnancy. We also sys tematically reviewed the published literature on both Bell's palsy and tinn itus in pregnancy and the puerperium using Medline from January 1966 to Oct ober 1998, and searched through the references from review articles and ori ginal reseal ch publications for further studies. Studies were limited to t hose published in the English language. We then pooled the rates of occurre nce for Bell's palsy according to trimester of pregnancy, and postpartum, a s well as the associated prevalence of pre-eclampsia or gestational hyperte nsion. We found that the majority of cases of Bells palsy arose during the third trimester (pooled event rate 71.1%, 95% confidence interval (CI) 64.1 -77.2), while almost none arose in the fir st trimester. During the postpar tum period, the distribution of Bell's palsy was 21.3% (95% CI 15.7-28.1) o f all cases, with the majority arising within days of delivery. Gestational hypertension or pre-eclampsia was present in 22.2% of cases (95% CI 12.5-3 6.4), well above the 5% rate in the general population. Only one paper prov ided data on tinnitus in pregnancy, with the distribution equal across all three trimesters. When compared to non-pregnant controls, the odds ratio fo r the development of tinnitus during pregnancy was 2.8 (95% CI 1.0-8.1). In conclusion, Bell's palsy, and perhaps, tinnitus, occur mole frequently dur ing the third trimester of pregnancy. Both may be presenting prodromal sign s of underlying early pl e-eclampsia. The pathophysiologic mechanism I elat ing these two entities to pre-eclampsia is also discussed.