HCG Levels for Twins
Are you pregnant and wondering if you could possibly be pregnant with twins? One indication that you might be pregnant with twins is HCG levels, although you cannot really know for certain from these readings alone.
What is HCG? HCG stands for human chorionic gonadotropin. This is a hormone which is created while a woman is pregnant. It comes at first from the embryo and later on from a component of the placenta called the syncytiotrophoblast. HCG is also produced in the pituitary gland.
What is the purpose of HCG? Human chorionic gonadotropin production leads to progesterone production. Progesterone is another hormone which alters the structure of the uterus so that it can support the fetus as its develops. HCG also protects the developing fetus from the mother’s immune system so that the immune system won’t reject the fetus.
HCG is produced very early in the pregnancy process, even before that first missed period—just 7-8 days after ovulation occurs. When a woman takes a blood or urine test, what the test is looking for is changes in the HCG levels. Tests can usually detect these levels 10-11 days after ovulation. During the earlier stages of pregnancy, human chorionic gonadotropin levels will tend to double every 2-3 days. 85% of normal pregnancies follow this pattern, but as you can tell, there’s room for a fair bit of variation. At about 8-10 weeks a pregnant woman will be producing a peak amount of HCG, and then the levels will drop again for the remainder of the pregnancy.
So does that mean that you can determine whether you might have twins from your HCG levels? Unfortunately the answer is “possibly, but not for certain.” The reason for this is that while human chorionic gonadotropin levels for twins are on average higher than those for single babies, there is so much variation that having a higher HCG might mean you have twins, but it also might mean you just have one baby. Likewise, having “normal” levels doesn’t mean you don’t have twins, especially in the earlier stages when the HCG production for twins is usually about the same as the HCG production for single babies.
One way to be more accurate is to try taking a blood test instead of a urine test. A blood test measures much more precise HCG levels than a urine test, so if you see higher numbers from a blood test, that’s a better indication than the levels in a urine test. The fact is though, this still won’t necessarily prove to you that you have twins.
You may want to consider just getting an ultrasound if you can afford it. An ultrasound will give you a much more accurate picture of what’s going on (literally!), especially as your pregnancy progresses and it becomes easier to interpret what’s on the screen.
So if you want to try and guess whether you’ll be having twins, look up a chart of average human chorionic gonadotropin levels for single babies and see if your levels are higher. Just remember that it might not mean you have twins at all—while you’re looking up those averages, try looking up some of the upper and lower ranges for HCG levels and you’ll see just how widely they can vary.