What is HCG? Role of the Pregnancy Hormone Explained

What is hCG hormone & hCG test?

HCG (Human Chorionic Gonadotropin) is known as the pregnancy hormone because it is produced by cells in the placenta and nourishes the egg after it has been fertilised and adheres to the uterine wall. A blood test can identify levels 11 days after conception, followed by a urine test 12-14 days later.

An HCG pregnancy test measures human chorionic gonadotropin (HCG) levels in the blood or urine. It can detect high HCG levels and establish if a person is pregnant.

HCG testing can also reveal whether a person's body is producing the proper levels of pregnancy-related hormones. Typically, HCG levels continuously grow during the first trimester, peak, then decline in the second and third trimesters.

How hCG supports pregnancy

During pregnancy, the placenta produces a hormone that is called human chorionic gonadotropin (hCG). HCG thickens your uterine lining to support the growing baby and signals your body to stop menstruation. HCG levels rise after conception and remain high until approximately 10 weeks of pregnancy.

HCG levels not only indicate pregnancy, but also help to determine whether the pregnancy is progressing normally. Very low HCG levels may indicate a difficulty with the pregnancy, an ectopic pregnancy, or the possibility of pregnancy loss. Rapidly rising HCG levels can indicate a molar pregnancy, which causes a uterine tumour to form. Doctors use numerous HCG measurements to track the progression of a pregnancy.

Also Read: Your cycle and time for conception

hCG levels in early pregnancy

HCG levels rise rapidly in the early days of the pregnancy. Each day the levels of this hormone double or triple while you are pregnant. The HCG levels however stop rising late in the first trimester. This leveling off may explain why many people feel relief from pregnancy symptoms like nausea and exhaustion around this time. 

Uses of hCG in fertility treatment

Luteinizing hormone (LH) regulates the final stages of human egg development before it is released from the ovary. It is also considered the "trigger" that causes the egg to ovulate or be released from the ovary. So HCG can be used to cause the final maturation and release of eggs during ovulation.

HCG is most commonly utilized to release eggs during clomiphene or gonadotropin cycles, as well as for final egg preparation prior to retrieval in IVF. HCG is also used to address ovulation issues such as luteal phase abnormalities because it promotes the formation of the corpus luteum (egg capsule) following the discharge of the egg from the ovaries.

Also Read: Everything You Need to Know about Phases of Menstrual

Timing hCG for conception

For persons who have failed to conceive after numerous efforts, the optimal time to inject human chorionic gonadotropin is during ovulation. Ovulation often happens 12 to 16 days before the next menstruation. Fertilisation and pregnancy are achievable within 24 hours of ovulation. As a result, the doctor will first use an ultrasound to inspect the follicles before injecting HCG to induce ovulation if the follicles are of sufficient size.

According to the ovulation schedule, the optimal time for sex is approximately 36 hours following the HCG doses. It is also preferable to have intercourse every other day for 3-4 days to boost the likelihood of pregnancy.

hCG and pregnancy tests

A pregnancy test determines whether or not you are pregnant. If your pregnancy test shows positive, you are pregnant. If the test is negative, you are not pregnant. Pregnancy tests detect human chorionic gonadotropin (HCG) by searching for high levels of HCG as HCG levels rise swiftly, doubling every several days throughout the initial weeks of pregnancy. Upon detecting high levels of HCG, the pregnancy test comes positive.

Also Read: Ectopic Pregnancy: Symptoms, Causes, & How It's Treated

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