Fig. 3From: Efficacy and safety of pertussis vaccination for pregnant women – a systematic review of randomised controlled trials and observational studiesIncidence or prevalence of hypertensive disorder. Forest plot of studies with data on hypertensive disorder in mothers as outcome. The analysis included data from three cohort studies with a total of 12,325 mothers received a pertussis vaccine during pregnancy and 115,829 mothers who did not. I-squared statistics for heterogeneity was 0%Back to article page