subject: hCG - Human Chorionic Gonada-what? by:Susan Tanner [print this page] ...Tropin. Human chorionic gonadotropin. Sound
Familiar? You may or may not have heard of hCG,
but if you have, it may be because you read it on the
box of your home pregnancy test. That's because
hCG is the basis of home pregnancy tests. It's also
the basis for the blood and urine pregnancy tests that
your doctor performs. But there is much more to hCG
than simply being an indicator of pregnancy.
HCG is a hormone produced by the placenta during
pregnancy. It begins being produced and released
into the blood almost immediately after the egg
attaches to the uterine wall. Since hCG is released
into the blood so soon after conception, it can be
detected there even before your first missed
menstrual period, as early as six days after
implantation. Its function is to prevent the disintegration of
the corpus luteum of the ovary and thereby maintain
production of one of the main pregnancy hormones,
progesterone.
HCG Levels
HCG levels rise steadily for the first 14 to 16 weeks
after your last menstrual period, doubling every 48-
72 hours in about 85% of normal pregnancies. After
this time, the levels will slowly decrease. The
increases in the hCG levels in early pregnancy can provide
invaluable information about your pregnancy and the
health of your baby. HCG levels return to zero shortly
after pregnancy.
HCG levels are often measured as part of a maternal
serum triple or quadruple screening test. These tests
are done by measuring three or four substances in a
woman's blood and are used to estimate the baby's
risk of certain problems or congenital birth defects.
The triple screen measures beta human chorionic
gonadotropin (beta-hCG), alpha-fetoprotein (AFP),
and a type of estrogen (unconjugated estriol or uE3).
The quad screen measures the hormone inhibin-A in
addition to the other three.
Abnormal hCG levels do not necessarily mean that
there is a problem. It could simply be due to a
miscalculation of pregnancy dating. Unfortunately
though, abnormal hCG levels could also indicate a
more serious issue. There are several things that could
cause a high or low hCG level, so you should be
retested within a few days to see how the levels are
changing.
A high hCG level could be an indicator of a multiple
pregnancy, in which there is more than one fetus
present, or a molar pregnancy. A low hCG level
could be an indicator of a possible miscarriage or
blighted ovum, or an ectopic pregnancy, where the
fertilized egg implants itself somewhere other than
the uterus.
By now it should be apparent that you will be hearing
quite a bit about hCG during your pregnancy, and
now you will know more about what you are
hearing.
About the author
Susan Tanner is a wife and mother of three. She is also the editor of pregnancy-guide.net. Pregnancy-Guide is an online community for mothers to find support and valuable information. Please visit Pregnancy-Guide at http://www.pregnancy-guide.net.
