Beta hCG values by week of pregnancy: table and meaning of the results
The Beta hCG hormone is produced by the body a few days after conception and its trend is one of the indicators of proper pregnancy progression. What are its values?
After fertilization, a woman’s body begins to produce a “pregnancy hormone” called human chorionic gonadotropin , commonly known as beta hCG .
The levels of this hormone increase rapidly in the first 8-11 weeks of pregnancy and can be detected about 10-11 days after conception with a blood test: the so-called beta hCG dosage (or more simply beta dosage ).
On this page, you will find a table of the minimum and maximum values of the beta hCG hormone according to the gestational age of the fetus, which you can compare with your results.
Alternatively, you can conveniently use our hCG beta calculator if you prefer .
ATTENTION: the dosage of beta hCG in the blood must be prescribed and evaluated by the gynecologist. The results, in fact, must be read together with other parameters and can vary according to the analysis laboratory.
For this reason, it is important to emphasize that a pregnancy can be normal even in the presence of low (or high) levels of hCG compared to the reference values.
Table of beta hCG values by week of pregnancy
How to read the hCG beta table
The first column of the table shows:
- the gestational age used by the gynecologist (weeks + days)
- the number of the week of pregnancy (first, second, third, …).
The other columns show the minimum and maximum values for beta hCG, measured in milli-international units per milliliter (mIU/mL) .
Attention: the weeks of pregnancy are not calculated from conception, but from the first day of the last cycle . If you don’t know what week you are, find out now with our pregnancy weeks calculator .
Beta hCG: the pregnancy hormone
Beta hCG: what is it?
Human chorionic gonadotropin or beta hCG is a hormone measurable in the bloodstream of the expectant mother after the fertilized egg has implanted itself in the uterus (about one week after conception) and for this reason it is commonly known as the pregnancy” .
What is it for?
Its main task is to stimulate the release of progesterone , another essential hormone for the continuation of pregnancy, which prepares the uterus to welcome and protect the developing embryo.
Growth of beta hCG
During gestation, beta hCG levels increase progressively as the weeks progress. In particular, in the first 8 weeks of pregnancy , the beta hCG values in the blood double every two days , and then stabilize until the moment of delivery.
In the case of an ectopic or extrauterine pregnancy (when the fertilized egg implants in places other than the cavity of the uterus), levels rise much more slowly .
However, it is up to the gynecologist to interpret the values and the trend of the beta : sometimes, in fact, perfectly normal pregnancies can have lower values than the reference ones.
Also remember that from the sixteenth week onwards, the beta hCGs are no longer measured , because there are more suitable tests to monitor the progress of the pregnancy and the growth of the baby, such as ultrasounds for example .
Beta hCG trend graph
In 85% of pregnancies that proceed normally, the amount of beta hCG doubles every 48 to 72 hours . This growth interval can also increase up to 96 hours as the pregnancy progresses.
Beta hCG values will peak in the first 8-11 weeks of pregnancy and then continue to decline for the remainder of the pregnancy.
Below, you can find a graph that helps you better understand how the beta hCG trend varies during pregnancy .
Beta hCG and pregnancy test
Home pregnancy tests work by detecting the presence of beta hCG in the mother-to-be’s urine. Typically, a common pregnancy test can identify the pregnancy hormone about 12 to 14 days after conception .
Currently there are very sensitive tests on the market, which are able to measure even low concentrations of this hormone and which can therefore be performed up to 5 days before the onset of menstruation .
When the pregnancy test is positive or of dubious interpretation , the gynecologist may suggest that a beta hCG dosage be performed .
It is important to note that this test is often not necessary. If your gynecologist does not deem it appropriate, it is probably because the pregnancy has already started and is progressing well.
Beta hCG in pregnancy: positive, negative or equivocal
Beta hCGs are always present in our body, even if in minimal quantities. If you are not pregnant, your beta hCG values should be between 0 and 10 mIU/mL .
Higher values in the absence of a pregnancy must be communicated to the doctor , who will evaluate the need for further investigation.
In general, when prescribing a beta dosage:
- a value below 5 mIU/mL is considered negative (absence of pregnancy);
- any value above 25 mIU/mL is considered positive and indicates that the pregnancy is ongoing ;
- a value between 6 and 24 5 mIU/mL is considered doubtful and for this reason the gynecologist may request a new dosage 2-3 days later to confirm pregnancy.
A single beta hCG reading can confirm pregnancy, but it’s not enough to give you an idea of how it’s progressing. To have a more accurate idea of the situation, it is necessary to carry out at least a couple of withdrawals at least a couple of days apart from each other.
When to worry?
Don’t worry if you get too low or too high – a lot depends on when you ovulated. For this reason, in case of levels outside the reference range, discuss with your gynecologist if and when to repeat the test.
Also remember that Beta hCG levels can increase differently from woman to woman and that it’s not the level that matters, but rather the pattern of growth over time.
Otherwise, if the beta hCG values decrease instead of increase, it could mean that the pregnancy has been terminated : to confirm this eventuality, it is always advisable to contact your trusted gynecologist or, in case of bright red discharge , go immediately to the emergency room .
Low beta hCG
A low level of beta hCG can have very different meanings. For this reason, in case of low beta hCG , it is necessary to repeat the test within 48-72 hours to monitor the variation of values over time.
The presence of low beta hCG can indicate:
- a late ovulation and therefore an incorrect dating of the pregnancy based on the date of the last menstruation;
- a possible ongoing miscarriage or biochemical pregnancy ;
- an ectopic pregnancy .
High beta hCG
Even a high level of this hormone can take on different meanings and should be reviewed within 48-72 hours to evaluate the change in values over time.
The presence of high beta hCG can indicate:
- incorrect dating of the pregnancy;
- a molar pregnancy ;
- a twin pregnancy .
At what beta hCG value is pregnancy visible in the uterus?
A normal transabdominal ultrasound (ie with the probe placed on the belly) can visualize a pregnancy in the uterus when the beta hCG in the blood exceeds the value of 6500 mIU / ml .
A transvaginal ultrasound (i.e. performed by inserting the probe into the vagina) allows instead to see a pregnancy when the value of beta hCG in the blood is higher than 1000 mIU/ml .
How do the values of beta HCG change after an abortion?
Usually, the values return to normal about 4-6 weeks after the miscarriage . The times vary a lot according to the period in which the pregnancy was interrupted, how it was interrupted and what the values were at the time of the interruption.
Typically, the values are checked at predefined intervals, until the betas drop below the value of 5.
What can distort the test result?
If the value is positive, pregnancy is almost always confirmed. With this test, in fact, false positives are extremely rare. However, there are some conditions and some medicines that can interfere with the readings obtained.
In particular, hCG-based drugs can distort the result . Usually these are medicines that are taken during fertility treatments and, in these cases, expectant mothers must respect the timing in performing the hCG beta test, to avoid obtaining false positives.
All other medications such as antibiotics, pain relievers, contraceptives or other hormonal drugs should not affect the dosage of this hormone.
Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.
Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.