Pulmonary Hypertension and Pregnancy Outcomes: Systematic Review and Meta-Analysis

Background: Traditionally, pulmonary hypertension during pregnancy has been associated with increased risk of adverse maternal and fetal outcomes. Therefore, the aim of this systematic review was to assess the risk of adverse pregnancy outcomes in pregnant women with pulmonary hypertension in recent decades. Methods: Electronic literature search of Medline, EMBASE and Cochrane library to find studies published in English literature from 1 Jan 1990 to 31st May 2018. Two authors independently extracted data from the eligible studies. Observational studies and case series describing adverse pregnancy outcomes in at least 4 pregnant women with pulmonary hypertension were included. The primary outcomes were maternal mortality and any pregnancy loss. The analysis included absolute risks and 95% confidence intervals (CI) for adverse outcomes using the DerSimonian-Laird random effects model. Heterogeneity was assessed by I2 statistic and visual plot. Results: Twenty studies captured data from 589 parturient describing 610 pregnancies. The majority (84.2%) of parturient had WHO Class I pulmonary hypertension. Pooled unadjusted data yielded maternal mortality of 11.5 (95% CI; 7.6-17.2) and total pregnancy loss of 22.8 (95% CI; 16.2-31.1). Prematurity and IUGR/SGA were reported by 7 and 8 studies and had pooled estimates of 51.7 (95% CI; 37.6-65.7) and 29.3 (95% CI; 20.9-39.5), respectively. The pooled estimates of cesarean delivery and general anesthesia were 72.1 (95% CI; 60.6-81.93) and 40.1 (95% CI; 26.4-55.5), respectively. Conclusions: Fetomaternal outcomes have improved in recent decades in pregnant women with moderate to severe grades of pulmonary hypertension. Though pregnancy should be discouraged, early pregnancy termination and planned early delivery with pulmonary artery pressure directed treatment appear to improve the fetomaternal outcome further. Funding Statement: The authors stated: "None." Declaration of Interests: None of authors reported any conflicts of interest. Ethics Approval Statement: PROSPERO, number: CRD42018099974.