What is hCG? (Human Chorionic
Gonadotropin) |
hCG is the hormone that is produced by the placenta
during pregnancy. This hormone is what is detected in both urine
and blood based pregnancy tests to produce a positive result. The
purpose of hCG is to keep the estrogen and progesterone levels at their
appropriate levels until the placenta has developed enough to take over
this function. During a normal pregnancy, the hCG levels will
steadily rise throughout the first few weeks of pregnancy. The hCG
levels will peak between the 8th to 12th week of pregnancy. |
|
What hCG level is considered
pregnant? |
More than 5 mIU/ml is considered a pregnant state.
Less than 5 mIU/ml is considered a non-pregnant state. To be
confident that a pregnancy is present a serum hCG concentration greater
than 25 mIU/ml is desirable. |
|
What types of hCG tests are there? |
There are 2 types of hCG blood tests. One is a
qualitative hCG test. The qualitative blood test gives only a yes
or no answer similar to the home pregnancy tests you can buy at the
store. The qualitative blood tests are normally set to indicate a
positive response at a level of 25 mIU/ml. A quantitative hCG
blood test measures the actual hCG level. A quantitative test is
the type of hCG test the doctors will do when doing a series of hCG
tests. |
|
What rate should my hCG levels
increase? |
Your hCG levels should increase by about 66% every 48
hours or double every 72 hours. |
|
How are my hCG levels monitored? |
First the doctor will do a "baseline" blood hCG level
test that will determine a starting level. Then every 48
to 72 hours the doctor will do another blood hCG level test to insure your hCG
levels are increasing an acceptable amount. |
|
What are the average hCG levels I
should expect during my pregnancy? |
hCG Level
Chart |
|
What does it mean if my hCG levels
are not increasing as expected or if they are declining? |
If your hCG levels are declining it may indicate that
a possible miscarriage has already occurred. If your levels are
not increasing as they should, it may indicate a pending miscarriage or
a possible ectopic pregnancy. Please be aware that some women will
have lower than normal hCG levels during pregnancy and will continue to
have an otherwise normal pregnancy. |
|
If my hCG levels are not increasing
as expected, what next? |
If your hCG levels are not increasing the expected
amount or they are declining, your doctor will generally look at your
progesterone level. If your progesterone level is also low or at
an abnormal level for your stage of pregnancy, you may be given
progesterone cream to help sustain the pregnancy. This cream comes
in the form of a vaginal suppository and your doctor may recommend
continuing its use until the 16th week of pregnancy. |
|
At what hCG level can a fetus be
seen during an ultrasound? |
A fetus can generally be seen by ultrasound around
2000 mIU/ml. If your levels are 2000 mIU/ml and you are between 4
and 6 weeks pregnant a yolk sac can generally be seen. If your
levels are 2000 mIU/ml and you are between 5 and seven weeks pregnant a
fetal pole can generally be seen. If your levels are 2000 mIU/ml
and you are between 5 and 8 weeks pregnant a heartbeat can generally be
seen. Ask your doctor for more information in your specific case. |
|
*Beta hCG
(Human Chorionic Gonadotropin) Levels |
|
LMP (Last Menstrual Period) |
mIU/ml hCG Levels |
|
|
3 Weeks |
3 - 50 |
|
|
4 Weeks |
3 - 426 |
|
|
5 Weeks |
19 - 7,340 |
|
|
6 Weeks |
1,080 - 56,500 |
|
|
7 - 8 Weeks |
7,650 - 229,000 |
|
|
9 - 12 Weeks |
25,700 - 288,000 |
|
|
13 - 16 Weeks |
13,300 - 254,000 |
|
|
17 - 24 Weeks |
4,060 - 165,400 |
|
|
25 - 40 Weeks |
3,640 - 117,000 |
|
There are a very wide range of "normal" levels of hCG.
For this reason, beta hCG tests are most useful when they are done in a
series. Beta hCG levels should increase by about 66% every 48
hours or double every 72 hours in the early weeks of pregnancy.
*The numbers in this beta hCG chart are to be used
only as a guideline and should be interpreted by your physician.
The above table shows typical ranges in hCG levels during pregnancy. |