hCG Levels by Week: Normal Pregnancy hCG Levels Chart
Once implantation occurs, the body begins to produce Human Chorionic Gonadotropic Hormone (hCG). This hormone is produced throughout pregnancy and is especially vital during the early stages.
Because it begins to rise rapidly in early pregnancy, testing for the presence of hCG in urine is one of the primary ways to determine whether or not an individual is pregnant. Throughout pregnancy, doctors may also test hCG levels as a way to monitor the health of a pregnancy.
If you are recently pregnant or trying to conceive, it’s understandable that you may have a lot of questions about what this hormone does and how you should be tracking it. To help, here is a look at everything you need to know about hCG including what it is, how to test for it, and how high your hCG levels should be throughout pregnancy. We’ll also cover how to interpret your hCG level results, and what it might mean if your hCG levels are too high or too low.
hCG is a type of pregnancy hormone that is vital in the early phases of pregnancy. Its primary role is to stimulate the corpus luteum to increase the production of progesterone, which in turn helps to:
- Support the growth of the uterus and uterine lining, and
- Prevent contractions that could be harmful to this growth.
Initially, hCG is produced by the cells that surround a developing embryo. The placenta then takes over the production of hCG once it is formed, and it then continues to produce hCG throughout pregnancy.
In the first trimester, hCG levels increase rapidly and reach their peak around week 10. For the remainder of the pregnancy, hCG continues to be produced. However, it typically remains at a steady level and it can even slowly decline towards the end of a pregnancy.
HCG is often referred to as the pregnancy hormone not only because of its critical role early in the process, but also because measuring hCG is the primary way to test for a potential pregnancy. Once an egg is fertilized and implanted in the uterus, hCG is detectable in the blood after seven days. It can also be accurately detected in urine approximately 12-14 days after conception.
It’s important to note that hCG is also produced in very small amounts by the pituitary gland. This means that both men and non-pregnant women have detectable amounts of hCG in their bodies (usually below 5mIU/ml). However, this is not high enough to be detected in a pregnancy test.
How does hCG behave in a normal pregnancy?
In a normal pregnancy, hCG will begin to rise rapidly once successful implantation has occurred. For the first four weeks of pregnancy, hCG will typically double every 48 to 72 hours. From week four to six, it may take three to four days to double. Once you have reached week 10, hCG no longer doubles but instead remains steady for the rest of the pregnancy. It can even slowly begin to slowly decline after week 17.
If hCG does not rise at the right pace, this could potentially be a cause for concern. Molar pregnancies, ectopic pregnancies, and miscarriages are all potential risk factors in cases where hCG levels are too high or too low. Regular hCG testing and monitoring combined with ultrasounds by your doctor can help you gain better insight into whether or not your pregnancy is healthy and developing normally.
For more information on the doubling time of hCG, check out our recent article hCG Doubling Time: What to Expect Before, During, and After Pregnancy.
hCG levels chart: What are normal hCG levels by week?
hCG levels during pregnancy
hCG levels at 3 weeks: 5-50 mIU/ml
hCG levels at 4 weeks: 5-426 mIU/ml
hCG levels at 5 weeks: 18-7,340 mIU/ml
hCG levels at 6 weeks: 1,080-56,500 mIU/ml
hCG levels at 7-8 weeks: 7,650-229,000 mIU/ml
hCG levels at 9-12 weeks: 25,700-288,000 mIU/ml
hCG levels at 13-16 weeks: 13,300-254,000 mIU/ml
hCG levels at 17-24 weeks: 4,060-165,400 mIU/ml
hCG levels at 25-40 weeks: 3,640-117,000 mIU/ml
hCG levels if not pregnant: 0-5 mIU/ml
Figures from The American Pregnancy Association.
How to test your hCG levels
Testing for hCG can be done using one of the two following methods. The first method is at home with a urine test (also known as a standard pregnancy test) and the second method is at the doctor’s office with a blood serum test.
At-home testing with a standard pregnancy test
At-home urine tests can be used if you are looking for confirmation that you are pregnant. Upon giving a urine sample, this type of hCG pregnancy test can let you know if your hCG levels are elevated enough to be considered pregnant. This threshold can vary depending on the brand of pregnancy test that you use, however, it is typically set above 5-25 MIU/ml.
Once your test is finished, you will then receive either a positive result (meaning you are pregnant) or a negative result (meaning you are not pregnant). A negative result can be frustrating if you are trying to conceive which is why it’s important to wait at least 12-14 days after your estimated date of conception before taking a urine pregnancy test.
Testing at the doctor’s with a blood serum test
The second method of testing for hCG is with a blood test. This type of test, sometimes called a “beta hCG test”, must be taken at your doctor’s office. Once your test results are back from the lab, your doctor will then be able to let you know what your hCG concentration level is, measured in mIU/ml. This precise information is the primary benefit of a blood test compared to a urine test, as it gives you insight into what your exact hCG levels were at the time of your test.
Another benefit of beta hCG testing is timing. Because hCG can be detected in blood much sooner than it can be detected in urine, beta hCG tests can be taken as early as one week after your estimated conception date.
This type of testing is particularly beneficial for couples with at-risk pregnancies looking to closely monitor their hCG levels. By testing for hCG regularly, these couples can gain critical insight into whether or not their hCG levels are rising at the right pace. If hCG levels are not rising as they should, a doctor can then conduct further testing and advise on the appropriate next steps.
Future testing solutions from Mira
The main downside of testing for hCG regularly at your doctor’s office is that it can be both time-consuming and expensive.
Even though you can use a pregnancy test to check if your hCG levels are elevated, there is currently no at-home testing solution that enables you to know your numeric hCG concentration level. However, Mira does plan to release hCG wands in the future to make this a possibility. Please check our shop regularly for further updates and details.
Interpreting your hCG levels results
Once you have your results, your doctor will be able to check if your hCG levels are within the right range for where you are in your pregnancy. In some cases, hCG levels may be higher or lower than normal. While this isn’t always a cause for concern, it does need to be investigated further by your doctor.
Here is a look at what low or high hCG levels might mean for a pregnancy.
What do low hCG levels mean for a pregnancy?
If your hCG levels are below the normal range, this could indicate any of the following.
Ectopic pregnancies happen when a fertilized egg implants itself outside of the uterus. The majority of ectopic pregnancies take place in a uterine tube, however, they can also occur in the ovaries or the abdomen.
Ectopic pregnancies can be life-threatening, especially in cases where the fallopian tube has ruptured. Speak with your doctor immediately if you are experiencing abnormal vaginal bleeding, lower back pain, or pelvic pain as these are common early symptoms of an ectopic pregnancy.
In some cases, lower than average hCG levels can indicate a miscarriage. This is because when a miscarriage occurs, the body stops all production of hCG. Other symptoms of miscarriage include abdominal pain, back pain, abnormal spotting and bleeding, fluid or tissue passing from the vagina, and loss of pregnancy symptoms.
Miscalculation of your conception date
Another possibility is that you may have miscalculated your conception date. If this is the case, your hCG levels will appear to be too low, even though they are actually increasing at the right rate based on where you are in your pregnancy.
What do high hCG levels mean for a pregnancy?
If your hCG levels are above the normal range, this could indicate any of the following.
Twins or multiples
If you are carrying twins or multiples, it is normal to have hCG levels that are higher than the normal range. While there is no specific chart or figure for how high hCG levels can reach when carrying twins, some doctors suggest that it can be up to 30-50% higher than a normal pregnancy.
Molar pregnancies occur when there is an abnormal growth of tissue in the uterus due to a genetic error. In a complete molar pregnancy, the emerging placenta grows and produces hCG, however there is no embryo. In a partial molar pregnancy, an embryo does exist however it has severe birth defects.
Molar pregnancies should be treated immediately by a doctor. In addition to elevated hCG levels, a molar pregnancy may also be accompanied by bright red or brown vaginal bleeding, pelvic pain, and severe nausea.
Higher than normal hCG levels can also indicate that your pregnancy may be at risk of Down’s syndrome. However, your doctor will need to conduct further blood testing and ultrasounds throughout your pregnancy to determine how high this risk level is.
Miscalculation of your conception date
Miscalculation of your conception date is another potential reason why your hCG levels may appear higher than they should be. If this is the case, you could be a few weeks further along in your pregnancy than what you and your partner had previously thought. With the help of an ultrasound, your doctor will be able to provide further insight into how far along in your pregnancy you actually are.
hCG levels FAQs
Because hCG plays such an important role in pregnancy, it’s normal to have some questions. Here are some of your most frequently asked questions about hCG answered!
When do hCG levels start to rise?
HCG levels begin to rise immediately after implantation. They continue to rise rapidly during the first four weeks of pregnancy, typically doubling every two to three days. At week 10 of pregnancy, hCG remains at a relatively constant level until the end of pregnancy.
When do hCG levels fall?
After week 17 of pregnancy, it is normal to see a slight decline in hCG levels. After pregnancy, hCG levels fall more rapidly and can take up to six weeks to return back to their pre-pregnancy levels, which is typically below 5 MIU/ml.
Do hCG levels change with twins?
If you are carrying twins or multiples, your hCG levels will also increase rapidly during the first few weeks of pregnancy and peak around week 10 – just like in a singleton pregnancy. However, there is a chance that your overall hCG levels will be up to 50% higher than what is considered the “normal” range for a single pregnancy.
Bear in mind though that this is not the case for every pregnancy with twins or multiples. You can still have a successful multiple pregnancy even if your hCG levels measure within the normal range.
For more information on twin or multiple pregnancies, check out our recent article hCG Levels & Twins: Understanding a Pregnancy with Multiples.