A meta-analysis was done to assess the effect of maternal lifestyle factors on pregnancy complication and perinatal outcome based on 14 primary studies. The statistical data was collected and condensed depending on the factors identified from the meta-synthesis. The data was analyzed using the forest plot method. The findings of the study revealed that maternal lifestyle factor like pre-pregnancy BMI ˃25kg/m2 had a statistical and clinical significance with the RR˃1. The other factors identified by meta-synthesis were poor dietary factors and lack of physical activity. The adverse outcome of pregnancy complications like GDM, PIH, anemia was prolonged labor, premature delivery, maternal mortality, IUD, IUGR, low birth weight, low Apgar score˂5 with RR˃1 and narrow confidence limit. Other maternal and fetal outcomes identified from meta-synthesis are SGA, LGA, birth asphyxia, stillbirth, congenital anomalies, and increased rate of admission to ICU. Thus the study concluded that there was a significant association between maternal lifestyle factors on complications like GDM, PIH, and anemia and had a significant relation in causing the adverse perinatal outcome.