Association of serum nitric oxide, free beta human chorionic gonadotropin and body mass index in first trimester pregnancy

Background: Pregnancy is a state of oxidative stress which arises from increased placental mitochondrial activity and production of reactive nitrogen species mainly nitric oxide (NO). NO is a potent vasodilator, which have pronounced effects on placental function which includes proliferation and differentiation of trophoblast. Human chorionic gonadotropin (hCG) is secreted by the syncytiotrophoblas. During pregnancy, free βhCG level can be first detected in maternal blood from 11th day after conception. Increased in NO synthesis acts as endocrine modulator of the placenta which promote secretion of free β hCG. The objective of this study was to estimate and compare the levels of βhCG and NO with different groups of BMI of pregnant women in first trimester.Methods: The study group comprises of 85 pregnant women within the age of 20-40 years with singleton pregnancy (11th-13th week + 6 days of gestation) who came for routine first trimester screening. Serum levels of free β hCG was analyzed by electrochemiluminiscense. NO was measured by kinetic cadmium reduction method. Statistical analysis used: data was expressed as mean±SD and median. Comparisons between different groups of BMI were done using Kruskal Wallis test.Results: There was significantly increased level serum NO with the increase in BMI and significantly decrease in serum levels of (p>0.05) free βhCG. We found significant positive correlation between NO and βhCG (p>0.05, r value 0.01).Conclusions: Early placental formation requires high amounts of angiogenesis and vasculogenesis. Its initiation, maturation, and maintenance are of critical importance. Failure to placental formation can lead to preeclampsia and/or intrauterine growth restriction (IUGR)