Many pregnant women are confused about hCG levels and what they mean. Human Chorionic Gonadotrophin or, hCG for short, is the hormone unique to pregnancy. It can be detected in urine and blood. hCG can be very important, especially hCG levels in early pregnancy, to women who are pregnant, but not very interesting to those who aren’t.
hCG is the hormone which is responsible for most early pregnancy symptoms. Those signs and symptoms which make women question if perhaps they are pregnant. Breast tenderness, feeling a little emotional, nausea and fatigue – they’re all due to hCG levels.
hCG is produced by the cells which will eventually become the placenta. Long before it is fully formed, the early placental tissue sends a message to the ovarian follicle where the egg was released. This area is called the corpus luteum. It plays an important role in influencing the production of oestrogen and progesterone. These hormones are responsible for building up a rich bloody lining in the uterus to feed the developing embryo before the placenta has formed. Without this, the chances of the embryo surviving would be pretty slim. Problems with the function of the corpus luteum may contribute to fertility problems and early miscarriage.
It takes around 2 weeks after conception for hCG to be detected in a hCG pregnancy test. Low levels of hCG may be detected in a woman’s blood 8-11 days after conception. hCG levels in early pregnancy are at their highest towards the end of the first trimester, before they gradually decline over the rest of the pregnancy. hCG levels can vary at different times of the day, and from week to week.
Some women seem to be very sensitive to the effects of hCG and from very early pregnancy, feel symptoms. hCG levels can vary between individual women and if they are carrying more than one embryo. Check here for more information on hCG levels.
Generally a woman’s hCG levels double every 72 hours. hCG levels in pregnancy reach their peak in the first 8-11 weeks of pregnancy and then tend to level off for the next two trimesters. This is why, in the first trimester (3 months) of pregnancy, symptoms can be so much stronger and intense.
Even the cheapest home pregnancy test is sensitive enough to detect hCG. However, it won’t actually give you any idea of what your hCG levels in early pregnancy are.
Non pregnant women |
Less than 10 U/L |
Borderline pregnancy result |
10 to 25 U/L |
Positive pregnancy test |
more than 25 U/L |
Pregnant women, about 4 weeks after the last menstrual period or LMP |
0 to 750 U/L |
Pregnant women, about 5 weeks after the LMP |
200 to 7,000 U/L |
Pregnant women, about 6 weeks after the LMP |
200 to 32,000 U/L |
Pregnant women, about 7th weeks after the LMP |
3,000 to 160,000 U/L |
Pregnant women, about 8 to 12 weeks after the LMP |
32,000 to 210,000 U/L |
Pregnant women, about 13 to 16 weeks after the LMP |
9,000 to 210,000 U/L |
Pregnant women, about 16 to 29 weeks after the LMP |
1,400 to 53,000 U/L |
Pregnant women, about 29 to 41 weeks after the LMP |
940 to 60,000 U/L |
For more information check here
Remember, these numbers are a guide. Every woman and her pregnancy are unique and what is normal for one may not be for another. If you have any concerns about your individual hCG readings, it’s important to see your health care professional.
There are a few reasons why a woman’s hCG can be particularly high - miscalculation of pregnancy dates, carrying a multiple pregnancy or very rarely, a molar pregnancy or a placental tumour. It is common for health care providers, if concerned, to recommend repeat testing with 48-72 hours to check for changes in the level of hCG.
Perhaps it’s too early in the pregnancy for levels of hCG to be high. It’s easy to miscalculate gestational age, especially for women who have irregular menstrual cycles. A blighted ovum, miscarriage or ectopic pregnancy can also result in low hCG levels.
It’s possible to have a false negative pregnancy test but it’s virtually impossible to have a false positive pregnancy test. Doing a test too early can lead to a false negative result.
Even if you do find out your hCG level, don’t make too much of it. A low reading of hCG can still lead to a healthy pregnancy and baby.
Dating a pregnancy or gestation from hCG readings alone isn’t ideal. This is because there is such a big variation between women, and what is considered “normal”.
Written and reviewed by Jane Barry, midwife and child health nurse on 12/01/20