If you’ve ever walked down the pregnancy test aisle you were probably bombarded with bright boxes advertising the chance to know before you’ve even missed your first period. Human chori-onic gonadotropin (hCG), also called the pregnancy hormone, is one of the first clues you may be expecting.
After the fertilized egg attaches to the uterine wall, cells developing in the placenta begin to produce hCG. In most normal pregnancies, levels double every 48-72 hours until they peak around the 11th week of pregnancy. Your OB/GYN can detect human chorionic gonadotropin through a blood test about 11 days after conception, with early detection urine tests effective after 12-14 days.
Human chorionic gonadotropin levels can help detect early pregnancy. False positives are rare, but false negatives can happen if you are too early in your pregnancy to have detectable hCG levels. Your OB/GYN may also use hCG to monitor your pregnancy if you have a history of miscarriage or experience bleeding and severe cramping.
By weeks 9-12, you may see hCG readings from 25,000 – 288,000 mIU/mL. Given the broad range of normal, your OB/GYN can’t definitively say whether your fetus is healthy or guess how far along you may be.
Low human chorionic gonadotropin levels don’t necessarily indicate a problem, but it could mean the due date was miscalculated. More serious reasons for a low hCG level include possible miscarriage or ectopic pregnancy.
Abnormally high hCG levels may mean you are further along in your pregnancy than pre-viously thought. High amounts of hCG are also present when you’re pregnant with multiples or in molar pregnancies.
If results come back abnormally high or low, your OB/GYN will likely recheck your hCG levels in a day or two. A transvaginal ultrasound is a more conclusive test to date your pregnancy and check the health of the fetus if there are any questions.
