True about hCG

Ans: B (Prevent involution of corpus luteum) hCG is produced by the syncytiotrophoblast of the placenta. Its value reach maximum levels ranging 100 IU & 200 IU/ml b/w 60-70 days of pregnancyIt can be detected in the material serum or urine as early as 8-9 days following ovulation.The rescued maintenance of corpus luteum till 6 wk of pregnancy is the major biological function ofhCG7- Dutta obstetrics 6th/ 58"It can be measured by radioimmunoassay & detected in blood as early as 6 days after conception0"- Ganong22th/449Human Chorionic Gonadotropin (hCG) - Dutta 6th/ 58, 186. 207# High level of hCG could be detected in - mu Itiple pregn ancy hydatiform mole or choriocarcinoma' & relatively high in pregnancy with a 21 - trisomy fetus (Dawn's syndrome }# Estimation of bhCG by ELISA is positive in 95% of ectopic pregnancies, A single estimation of bhCG level either in serum or in urine confirms pregnancy but cannot determine its location. The suspicions findings are lower concentration of bhCG compared to normal intra-uterine pregnancy & doubling time3 in plasma fails to occur in 2 days.Maternal serum chorionic gonadotropin is approximately doublet in twins than those of singleton pregnancies. But their values cannot diagnose clearly a twin from a single fetus.hCG : Review of facts# It is a glycoprotein 1 consisting of a hormone non-specific & a hormone specific b subunit.# hCG is chemically & functionally similar to pituitary luteinising hormone'3. The a subunit is biochemically similar to LH, FSH & TSH where as the P subunit is relatively unique to hCG.# It is produced by the syncytiotrophoblast of the placenta and secreted into the blood of both mother & fetus# Half life of hCG is about 24 hours# By radioimmunoassay it can be detected in the maternal serum or urine as early as 8-9 days'3 following ovulation. In early pregnancy, the doubling time of hCG concentrations is plasma is 1.4-2 days1'. The blood & urine values reach maximum levels ranging 100 IU & 200 IU/ml b/w 60-70 days of pregnancy# It is commercially obtained from the urine of pregnant women- Shows Gynaecology 14th/ 137# The rescue & maintaince of corpus luteum till 67 weeks of pregnancy is the major biological function of hCG.