What Your HCG Levels Might Mean During Pregnancy
Pregnancy comes with a slew of new terms and lingo to learn. And given that you probably don’t have a background in obstetrics, it’s understandable to have questions. One medical acronym that may come up early on in your pregnancy is hCG. It stands for human chorionic gonadotropin, and it can give you—and your doctor or midwife—some insight into how your pregnancy is progressing. But what is hCG exactly, and what can your hCG levels mean? Here’s what you need to know.
In this article:
What is hCG?
Why doctors calculate hCG levels?
Normal hCG levels by week of pregnancy
What do high hCG levels mean?
What do low hCG levels mean?
At a basic level, hCG is a hormone that supports your pregnancy, explains Christine Greves, MD, an ob-gyn at the Winnie Palmer Hospital for Women & Babies in Orlando, Florida. “It’s very important in establishing and maintaining the pregnancy through helping with the placenta and development of the early embryo,” she says. And, yes, it may also be what’s driving your morning sickness and causing a few other early pregnancy symptoms, according to the Mayo Clinic.
The cells of your placenta, the organ that provides oxygen and nutrients to your growing baby, start producing hCG about 10 to 11 days after you conceive, says Kjersti Aagaard, MD, PhD, a professor of obstetrics and gynecology at Baylor College of Medicine in Houston, Texas. “hCG’s claim to fame is that it is the hormone that is detected on both urine and blood pregnancy tests,” she says, noting that this is also known as beta-hCG levels.
Urine pregnancy tests can detect hCG levels when they reach 20 to 50 milli-international units/mL, while blood tests are positive at 5 milli-international units/mL, says Julie Lamppa, APRN, a certified nurse-midwife at the Mayo Clinic and author of Obstetricks. That typically translates to getting a positive urine pregnancy test around the time that your period is due. “It usually takes about two weeks after conception for hCG to be high enough in your urine to be detected,” Greves says.
If you’re anxiously waiting for a positive pregnancy test result, try taking your test early in the day. In general, “first morning urine is recommended because it’s when the urine is the most concentrated and therefore lower levels can be detected more quickly,” says Melissa Goist, MD, an ob-gyn from the Ohio State University Wexner Medical Center. If you get a negative, you can wait and try again; in a healthy pregnancy, hCG levels tend to double every 72 hours in the early days and weeks of pregnancy, according to the American Pregnancy Association
“Once a pregnancy test turns positive, most commonly there is no reason to assess beta-hCG level,” Aagaard says. “The overwhelming majority of pregnancies will never have a reason to check a beta-hCG level.” There are a few specific scenarios where your beta-hCG levels might need to be checked, though. “These include situations where we’re trying to decipher whether a very early pregnancy is developing normally in the uterus, or if there is a risk of an inevitable miscarriage,” Aagaard says. “To decipher this, we have to measure the beta-hCG twice two to three days apart.” Basically, the first level gives your doctor a baseline, the second helps them determine if hCG is rising as expected or declining prematurely. The latter could indicate a potential pregnancy loss.
Lamppa adds that if there’s the suspicion of an ectopic pregnancy (when implantation occurs outside of the uterus), measuring hCG level can be revealing. Of course, a hCG blood test alone isn’t diagnostic, and an ultrasound is necessary to confirm, notes the Cleveland Clinic.
Another scenario that might warrant more thorough testing of your hCG levels in pregnancy? if you’ve conceived through in-vitro fertilization (IVF), your doctor might monitor your levels more closely, says Lamppa.
Levels of hCG typically increase until a certain point in your pregnancy and then begin to fall. “Initially, hCG is secreted to maintain the corpus luteum, which is supplying progesterone to the pregnancy,” Lamppa explains. “hCG will rise and peak around eight to 10 weeks and then start to decrease.” When this happens, your placenta has developed to the point of taking over and starts to supply progesterone to your pregnancy to help it progress, she says.
While there is a range of hCG levels that doctors expect to see during certain parts of your pregnancy, everyone’s numbers—and normal hCG levels by week—are a bit different. This is due to the number of trophoblastic cells, which are cells that help your developing embryo attach to your uterus, protect your embryo and form part of your placenta, Goist says. The exact number is “different with each pregnancy,” she adds.
If you’re pregnant with twins or multiples, your hCG levels may be higher than if you were having a single baby, Greves says. But a high hCG level doesn’t automatically mean you’re expecting more than one baby. Again, levels of hCG can vary by person and pregnancy. And, FYI, while you may have seen hCG levels charts floating around the internet telling you what your hCG levels should be at certain points in your pregnancy, know that most ob-gyns are hesitant to validate them and don’t use them to discern anything. “Clinically speaking, as providers we don’t even look at these, nor depend upon them,” Lamppa says. hCG levels in pregnancy are just too subjective.
High levels can be normal with a singleton pregnancy or a multifetal one—meaning, twins, triplets or more, Lamppa says. A high level can also happen with an ectopic or molar pregnancy, which is a pregnancy that’s not viable.
Don’t panic if you learn your hCG levels are on the low side—it usually doesn’t mean anything, Aagaard says. She adds that, for this reason, doctors and midwives don’t tend to check beta-hCG unless it’s deemed necessary. “It most commonly leads to more testing and increased anxiety,” she says.
It’s true that early on, declining levels could mean a pregnancy is not developing properly. On the flip side, lower levels could also be normal “based on how far the pregnancy has advanced,” Lamppa says.
How to increase hCG levels in early pregnancy
It’s natural to want to do everything you can do to maintain a healthy pregnancy. It’s stressful knowing that declining hCG in early pregnancy might mean an impending miscarriage. Unfortunately, there’s nothing you can do to raise (or lower) your hCG levels in pregnancy. This is one of those things you simply can’t control.
If your doctor or midwife is keeping tabs on your levels of hCG and you have questions, it’s important to bring them up. Otherwise, doctors say this isn’t something to worry about.
About the experts:
Kjersti Aagaard, MD, PhD, is a professor of obstetrics and gynecology at Baylor College of Medicine. She received her medical degree from the University of Minnesota Medical School in Minneapolis.
Christine Greves, MD, is an ob-gyn at the Winnie Palmer Hospital for Women & Babies in Orlando, Florida. She received her medical degree from the University Of South Florida College Of Medicine.
Melissa Goist, MD, is an ob-gyn from the Ohio State University Wexner Medical Center. She received her medical degree from the Medical College of Ohio at Toledo.
Julie Lamppa, APRN, is a certified nurse-midwife at the Mayo Clinic and author of Obstetricks.
Please note: The Bump and the materials and information it contains are not intended to, and do not constitute, medical or other health advice or diagnosis and should not be used as such. You should always consult with a qualified physician or health professional about your specific circumstances.
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