Relation between HCG level and Normal Pregnancy

HCG (Human Chorionic Gonadotropin) also called hormone of pregnancy, which is produced by cells that become placenta of developing embryo (trophoblast cells). Generally, the pregnancy test in an IVF cycle is scheduled two weeks after the embryo transfer to check the HCG level. In normal condition, the secretion of hormone is high enough to be detected in blood or urine.

If the HCG level is greater than 5 MIU/ ml then the test is repeated two days later and it should rise appropriately. Normally, the HCG hormone level in blood doubles every 48-72 hours. The instantaneous increase in HCG level indicates normal and healthy pregnancy. 

However, the slow rise was believed to be associated with an abnormal intrauterine pregnancy or a tubal pregnancy.  Doctors ensure HCG level in blood monitoring during first few weeks of pregnancy.

Facts about HCG levels and pregnancy

It has been determined that HCG levels determined 13-15 days after fertilization are higher in pregnancies from cleavage-stage day 3 embryos than those achieved through the transfer of blastocysts on day 5. So, it is advised to get the HCG tests from a single laboratory to avoid discrepancies as a single HCG level cannot differentiate between miscarriages and ectopic pregnancies. 

Doctors use a combination of HCG levels on day 15 and 22 after embryo transfer to predict pregnancy outcome. The rate of increase in HCG level is important, higher the percentage, better the delivery rate. Patients with Ovarian Hyperstimulation Syndrome (OHSS), the HCG levels can vary due to diluted blood vessels.

Initial HCG level might be higher in women carrying twin or triplets. However, the rate of rise is similar as singlet. Since, the HCG level is an important diagnostic tool, the doctors use the HCG levels with ultrasound to diagnose normal pregnancy.  

Dr Neeraj Pahlajani