Once you know you're pregnant, your next concern will likely be, "Is my baby developing normally?" Measuring your blood level of the pregnancy hormone human chorionic gonadotropin, or HCG, produced by the growing placenta, every few days can help determine whether your pregnancy is progressing well. Doctors don't usually test your HCG blood levels unless you've had fertility treatment or have pregnancy complications.
The placenta, which supplies nourishment to your baby, grows rapidly in the early phase of pregnancy. As it grows, the placenta produces more HCG, causing your blood levels to rise until around week 8 to 10 of pregnancy. A single HCG reading generally doesn't tell you as much as serial readings taken every few days. HCG levels normally double approximately every 48 hours in early pregnancy. However, you may still have a perfectly normal pregnancy even if your HCG levels don't fall within the average range at a given time point.
Normal HCG Levels
At 4 weeks of pregnancy, or 2 weeks after ovulation, HCG levels in a normal pregnancy typically fall between 10 and 750 mIU/mL, according to the website Perinatology.com. However, expected ranges may vary somewhat from one testing laboratory to another. If you're having more than one baby, your HCG level will often be higher than the usual normal range. If you have an ectopic pregnancy -- where the fetus begins to grow outside the uterus -- your HCG levels may be lower than normal. Other pregnancy problems can also cause a low HCG level. Talk with your doctor if you have concerns about your HCG level.