Low Maternal Serum Folic Acid as Risk Factor of Preterm Delivery

Introduction: Preterm delivery increases the risk of infant mortality and morbidity higher than that of term born babies, so it is still a big problem in the field of obstetrics. Preterm delivery is not only influenced by anatomical factors, but nutritional status can also be a risk factor. Various studies have reported the role of folic acid on the risk of preterm delivery. Folic acid is thought to play a role in preterm labor through inflammatory and infectious pathways, this pathway is triggered by low serum folic acid levels interfering with Hcy metabolism which causes an increase in Hcy levels. High levels of Hcy in serum induce oxidative stress processes in vascular tissue and placental endothelium. The occurrence of oxidative stress and cell apoptosis will release proinflammatory mediators that cause preterm labor. This study aims to prove the role of maternal serum folic acid levels in preterm delivery. Methods: This study used a case-control design that was carried out from January 2021 to June 2021. The target population of the case in this study was pregnant women in the process of preterm labor with control of preterm pregnant women. The sample in this study was taken by consecutive sampling (non random sampling). Examination of folic acid from venous blood samples was carried out using the ELISA method. Results: This study involved 27 cases (preterm delivery) and 27 controls (preterm pregnancy). In this study, serum folic acid levels were found to be lower in the case group compared to the control group (cases vs. controls: 9.86 ± 1.93 ng/mL vs. 13.59 ± 1.24 ng/mL), all samples the case and control groups received folic acid supplementation. In this study, the maternal serum folic acid threshold was found at a concentration of 12.2 ng/mL, the researchers also obtained a risk value (OR) of 5.71 which indicated that pregnant women with serum folate levels below the value of 12.2 ng/mL had a risk of preterm delivery. 6 times greater when compared to pregnant women with serum folate levels above this value. Folic acid plays a role in the developmental phase of EVT, angiogenesis, and secretion of MMP which is important in placental development. Low serum folic acid levels also increase the process of angiogenesis, expression of MMP2, MMP3, and MMP9 thereby increasing the risk of preterm labor. Conclusion: Low folic acid serum level in pregnancy is a risk factor for the occurrence of preterm labor by six times.