According to Doctor Phan Ha Minh Hanh from the Assisted Reproductive Technology Department at Tam Anh General Hospital - District 8, when an embryo implants in the uterine lining, the hormone HCG is produced by the trophoblast cells of the embryo, which will later form the placenta. This hormone appears in a woman’s blood and urine as early as 10 days after conception, typically doubling every 48-72 hours. It peaks around weeks 8-10, then gradually decreases and remains stable throughout the pregnancy.
The optimal time to measure beta-HCG blood levels is 12-14 days after embryo transfer, which helps determine pregnancy. Testing earlier may lead to inaccurate results. A beta-HCG level above 25 mIU/mL indicates pregnancy. In a follow-up test after 48 hours, a beta level increase of 1.5 times or more suggests healthy embryonic development.
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Doctor Minh Hanh consults with a patient. Photo illustration: Nguyen Thang |
Doctor Minh Hanh consults with a patient. Photo illustration: Nguyen Thang
If the initial beta-HCG level is above 25 mIU/mL, but in the follow-up test after 48-72 hours, the beta level increases minimally or declines, accompanied by unusual symptoms like vaginal bleeding or a dull abdominal pain, women should immediately consult an obstetrician-gynecologist or a fertility specialist.
A beta-HCG level below 5 mIU/mL indicates that the embryo transfer was unsuccessful. Doctor Hanh advises couples to remain calm and discuss post-transfer care with their doctor, planning for future treatments to optimize the chances of success in subsequent embryo transfers.
This test is 99% accurate. To avoid errors, Doctor Hanh offers the following advice.
Women using home pregnancy tests should collect a mid-stream urine sample first thing in the morning and follow the test instructions carefully.
For HCG blood tests, fasting is not required, but women should avoid stimulants for 12-14 hours prior. Some medications can affect test results; women should discuss any medications with their doctor before the test.
Beta-HCG test results do not determine the sex or developmental status of the fetus. Women should attend regular prenatal checkups, undergo recommended tests or diagnostic procedures to effectively monitor fetal health.
Hoai Thuong
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