OBJECTIVE:The present systematic review and meta-analysis investigated the effects of hydralazine in maternal, perinatal and neonatal outcomes in pregnant women with hypertensive disorders, compared with other antihypertensive drugs. DESIGN AND METHOD:Bibliographic search was performed in medline (PubMed), cochrane central register of controlled trials (CENTRAL), cochrane pregnancy and childbirth groupʼs trial register and clinicaltrials.gov for randomized controlled clinical trials. Two authors independently extracted data and assessed risk of bias for each outcome. RESULTS:Twenty studies with 1283 participants were included. 626 of them received hydralazine and 657 other antihypertensive treatments such as labetalol, nifedipine, ketanserin, diazoxide, urapidil, isradipine and epoprostenol. Women receiving hydralazine had higher end follow-up heart rate (WMD13.43, 95%CI0.08 to 26.79), while hydralazine was also associated with increased number of side effects (RR1.21, 95%CI1.01 to 1.45). Finally, infants of mothers that had received hydralazine had lower birthweight compared to other treatments (WMD−135.30, 95%CI−260.95 to −9.65). CONCLUSIONS:These results do not support the use of hydralazine as first line treatment for hypertension in pregnancy. Hydralazine was associated with more maternal side effects, lower birthweight and higher maternal heart rate.