HCG Levels in Pregnancy
The following information is from Anne Frye (CPM)'s book: "Understanding
Diagnostic Tests in the Childbearing Year" 6th edition
p. 108 "Normal hCG Levels in Early Pregnancy"
"HCG is detectable in the blood serum of approximately 5% of pregnant women by 8
days after conception, and in virtually all the rest by 11 days. HCG rises progressively
from conception. Levels double on the average, every 30.9 hours until values reach
6500 mIU/ml (6,500 IU/L) at approximately the eighth week after the last menstrual
period (LMP). After that the rate of rise becomes individualized, peaking between the
60th and 70th day (9 to 10 weeks) LMP. HCG decreases slightly between the 12th and
16th week post LMP, and then remains constant until birth. "
p. 111 "To Diagnose Pregnancy"
"A blood serum level of less than 5 mIU/ml (5 IU/L) can be considered negative and
anything above 25 mIU/ml (25 IU/L) positive for pregnancy. If you are unsure, repeat
the test in two days to see if there is an upward trend, which indicates pregnancy."
"Levels higher than expected for the weeks pregnant may be due to multiple gestation
or inaccurate dates. ... Levels for normal pregnancy fall within the following wide
ranges. You will note a discrepancy between the ranges of normal in the two tables
below. The actual level can vary widely, and is not as significant as the amount and rate
of rise, particularly before 10 weeks."
p. 112
PREGNANCY STATUS SERUM hCG LEVELS
from conception
7 days
from LMP
(mIU/ML or IU/L)
3 weeks
0 to 5
14 days
28 days
3 to 426
21 days
35 days
18 to 7,340
28 days
42 days
1080 to 56,500
35 - 42 days
49 - 56 days 7,650 to 229,000
43 - 64 days
57 - 78 days 25,700 to 288,000
57 - 78 days
79 - 100 days 13,300 to 253,000
17 - 24 weeks
2nd trimester 4060 to 65,400
25 wks to term
3rd trimester 3640 to 117,000
After several days postpartum
nonpregnant levels (<5)"
"Results in Twin Gestation"
"Quanitative serum hCG tests detect multiple pregnancy approximately 9 weeks earlier
than ultrasound. One small study (Jovanovic, 1977) found hCG levels in 15 singleton
and 9 twin pregnancies were as follows:
DAYS
FROM
LMP
hCG in
SINGLTON
AVERAGE
GESTATION
RANGE
hCG in
AVERAGE
TWIN
GESTATION
RANGE
28
64.7
9.4 to 120
64.7
9.5 to 120
33
450
300 - 600
1,500
200 to 1,800
36
1,500
1,200 - 1,800
19,200
2,400 to 36,000
40
3,600
2,400 - 4,800
58,344
8,700 to 108,000
45
36,000
12,000 - 60,000
126,000
72,000 to 180,000
70
120,000
96,000 - 144,000 414,000
348,000 to
480,000"