Background: Premature Rupture of Membrane (PROM) may cause maternal and neonatal morbidity and mortality. This study aimed to investigate the risk factors related to PROM in pregnant women below <35 years old.Subjects and Method: This cross-sectional study was conducted in Kertha Usada General Hospital, North Bali, Indonesia. We collected 224 repoductive women using consecutive sampling. The dependent variable was premature rupture of membrane. The independent variables were gravidity status, gestational age, body mass index (BMI), history of caesarean section, miscarriage, infection, and anemia. Data of infection was obtained from examination, such as neutrophil, lymphocyte, platelet, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR). We also obtained Hb, MCV, and MCH as laboratory parameter of anemia. The data were analyzed by a multiple logistic regression.Results: Multigravida (or= 0.04; 95% CI= 0.01 to 0.27; p= 0.001) and MCH >34 pg (OR= 0.10; 95% CI= 0.01 to 0.86; p= 0.036) decreased the risk of premature of rupture membrane in women of reproductive age.Conclusion: Multigravida and MCH >34 pg decrease the risk of premature of rupture membrane in women of reproductive age.Keywords: premature rupture membraneCorrespondence: Putri Chairani Eyanoer. Department Community and Preventive Medicine, Faculty of Medicine, Universitas Sumatera Utara, Medan, Indonesia. Email: putrieyanoer@usu.ac.id. Mobile: +62-813 7023-2513Journal of Maternal and Child Health (2020), 5(4): 576-586https://doi.org/10.26911/thejmch.2020.05.04.04