Background: According to the World Health Organization, obesity is considered a pervasive global epidemic with significant medical and social implications. In antenatal mothers, the prevalence varies from 40% in Western countries to 12% in India which leads to life-threatening complications—preeclampsia and eclampsia. Aim: This study delves into the association between body mass index (BMI) and preeclampsia, among primi antenatal mothers with pregnancy-induced hypertension (PIH). Methods: An observational cohort (prospective) study was conducted among 150 primi antenatal mothers with pregnancy-induced hypertension in Government Headquarters Hospital, Tamil Nadu, India. Demographic data, body mass index, and pregnancy outcomes were assessed. Statistical analysis was performed using the SPSS 28.0 version. Results: Among 150 pregnant women, 63 (42%) were overweight, and 13 (8.7%) were obese. Higher BMI was significantly associated with maternal complications, especially preeclampsia (P < 0.001). Moreover, other complications such as abruptio placenta, pulmonary edema, eclampsia, and postpartum hemorrhage were not significantly associated with BMI. Conclusion: The study calls attention to the persistent link between BMI and preeclampsia, emphasizing the need for comprehensive strategies aligned with the Sustainable Development Goal. Despite ongoing efforts, the study suggests a lack of substantial change in the prevalence of preeclampsia associated with increased BMI, prompting the exploration of innovative interventions to address weight-related factors during pregnancy for improved maternal and neonatal well-being. © 2024 Elsevier B.V., All rights reserved.