Download HCG

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HOMEWORK of OB/GYN
on Human Chorionic
Gonadotropin (HCG)
87KE4 team3
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I.
II.
III.
IV.
What is HCG?
How to test HCG?
What is the clinical significance of
HCG detection?
Home pregnancy tests (HPTs)
I.
 1.hCG
HCG
is glycoprotein hormone
produced by normal trophoblast
cells(合体滋养细胞） of the placenta
during pregnancy.
 2.hCG
production starts just a few
days after conception（受孕）, before
implantation in the uterus.
 hCG enters the maternal circulation
almost immediately after
implantation， about day 21 of the
menstrual cycle.
 3.hCG
is composed of two subunits,
alpha and beta
 4.The
alpha-subunit is identical to
that of the pituitary glycoprotein
hormones:
 lutenizing hormone (hLH),
 follicle stimulating hormone (hFSH)
 thyroid stimulating hormone (hTSH).
 5.The
ß-subunits of the glycoprotein
hormones are unique, giving them
their different biological
characteristics.
 6.physical
function:
 1) 作用于月经黄体，增加甾体激素的分泌，
以维持妊娠
 ２）有促卵泡成熟活性，促甲状腺活性，
促睾丸间质活性
 ３）与尿促性素合用能诱发排卵
 ４）激素屏障：抑制淋巴细胞活性
Ⅱ.How to test HCG?
qualitative urine or blood hCG
test is ordered as early as 10 days
after a missed menstrual period if a
woman wishes to confirm whether or
not she is pregnant
 １.A
2.Affecting factors
 1)Tests performed too early
 2) a false negative result in very dilute
urine. Patients should not drink large
amounts of fluid before collecting a urine
sample for a pregnancy test.
 3)drugs: （1）diuretics and promethazine
(异丙嗪) false-negative urine results. （2）
anti-convulsants, anti-parkinson drugs,
hypnotics, and tranquilizers false-positive
results.

test: hCG kits can detect a
wide and varying range of different
hCG-related molecules in serum or
urine samples.
 ３.Special
The molecules detected include
5 groups:
 1).non-nicked
hCG (完整的HCG) the
active hormone
 2).nicked hCG （缺口hCG）
 3).hyperglycosylated
HCG(高糖基化
HCG)最新研究表明如果此型HCG在妊娠七
周时维持在较高水平不下降则预示妊娠异
常
 4).asialo hCG (缺乏唾液酸基的HCG),
 5) hCG-CTP or free ß-subunit can
ⅢWhat is the clinical
significance?
 1.
Normal pregnancy
 FIGURE
 The
"normal" ranges for the HCG in
blood pregnancy test

1) The concentration of may reach up to
150,000 mIU/ml in both serum and urine.
 2)hCG levels rise exponentially for the first
8 weeks of pregnancy,
 3) reaching a peak at 10 weeks after the
last menstrual period.
 4)In the following 10 weeks levels slowly
decline to approximately one fifth of peak
levels and remain around one fifth of peak
levels until term
 2.
Early pregnancy loss (EPL)
This is an embryo which fails to
implant properly in the uterus, or is
rejected by the uterus. It is followed
by a normal or slightly heavier than
normal menstrual period.

hCG concentration reaches a peak
after 2 weeks conception (28 days
after start of last menstrual period)
at 10 to 100 mIU/ml, then rapidly
declines. Normal or slightly heavier
than normal menses follow.
 3.
Ectopic or extrauterine
pregnancy
In women with extrauterine or
ectopic pregnancies, unduly low hCG
levels may be detected.
 最新研究表明如果腹腔血beta-HCG定性检
查为阳性者100%为异位妊娠
4
Gestational Down syndrome
 5 Hydatidiform mole hCG
concentration may be as high as
2,000,000 mIU/ml.
 6 Persistent trophoblast
disease or persistent mole
7
Choriocarcinoma
 8. Germ cell, bladder and other
non-trophoblastic malignancies
 9. pituitary hCG production
 10. false positive hCG production
Ⅳ HPT( Home pregnancy tests)
 use
midstream urine
 you need to hold the absorbant
tip of the stick in the cup of urine
for 5-10 seconds
 In the result window, the tests
usually give a line or a plus.
 Examples of line tests.doc