HCG Level in Early Pregnancy

There are numerous questions about HCG levels and what they mean. Two of the most popular are: how fast is my level rising, and how do my levels compare to normal pregnancies.

This simple JavaScript applet that takes two HCG levels, the number of days between those samples, and calculates the number of hours it took to double. Before drawing any conclusions from the calculated doubling time, I highly recommend reading BabyMed's HCG page in its entirety. As you get further along in your pregnancy and the HCG levels get higher, the expected doubling time increases:

Another favorite of those taking HCG tests is: do my levels and/or doubling times indicate more than one? Everyone hears that fast doubling times might indicate multiples but I found no evidence of that in my unscientific survey on INCIID. I found that high levels of HCG on a given DPO indicated twins.

Here's the calculator. Type in your numbers and the doubling time will be calculated automatically.

Note: The Daily Rate is how much your HCG level rises per day for the calculated Doubling Time. For example, if your daily rate is 1.50 and the first HCG Level was 100, your HCG level would have been 150 on the next day.

I've re-done the Advanced Fertility Center's HCG table to list the values by common days-post-xxx standards instead of the awkward days-post-HCG they use. The first table is the original AFC table, second is days post retrieval, third is days post-day3 transfer, and the fourth is days post-day5 transfer.

*Days Post-HCG*
DPH	High	Avg	Low
14	119	48	17
15	147	59	17
16	223	95	33
17	429	132	17
18	758	292	70
19	514	303	111
20	1690	522	135
21	4130	1061	324
22	3279	1287	185
23	4660	2034	506
24	10,000	2637	540

*Days Post-Retrieval*
DPR	High	Avg	Low
12	119	48	17
13	147	59	17
14	223	95	33
15	429	132	17
16	758	292	70
17	514	303	111
18	1690	522	135
19	4130	1061	324
20	3279	1287	185
21	4660	2034	506
22	10,000	2637	540

*Day3 Transfer*
DPT	High	Avg	Low
9	119	48	17
10	147	59	17
11	223	95	33
12	429	132	17
13	758	292	70
14	514	303	111
15	1690	522	135
16	4130	1061	324
17	3279	1287	185
18	4660	2034	506
19	10,000	2637	540

*Day5 Transfer*
DPT	High	Avg	Low
7	119	48	17
8	147	59	17
9	223	95	33
10	429	132	17
11	758	292	70
12	514	303	111
13	1690	522	135
14	4130	1061	324
15	3279	1287	185
16	4660	2034	506
17	10,000	2637	540

There was a recent study (Homan, et al, Fertility and Sterility, Feb2000) that looked at the HCG level at 16dpo (13dp3dt or 11dp5dt). It found that, for a given HCG at 16dpo, the chance of a ongoing pregnancy at 20w was:

Here is the data in graph format. The upper line is for women less than 40yo and the lower line is for those more than 40yo.

The majority of women had HCG levels in the 100-500 range, with most of those above 200. This agrees with the tables from AFC where the average at 16dpo was 292 (range 70-758).

Fertil Steril 1992 Aug;58(2):373-7

Can a single, early quantitative human chorionic gonadotropin measurement in an in vitro fertilization-gamete intrafallopian transfer program predict pregnancy outcome?

Heiner JS, Kerin JF, Schmidt LL, Wu TC

University of California-Los Angeles (UCLA), School of Medicine.

STUDY OBJECTIVE: To assess the predictive value of a single serum human chorionic gonadotropin (hCG) measurement obtained on day 14, 15, or 16 after transfer in in vitro fertilization or gamete intrafallopian transfer pregnancies.

DESIGN: Retrospective.

SETTING: Assisted reproductive technology (ART) programs.

PATIENTS: One hundred thirty-four consecutive pregnancies from two ART programs were reviewed.

RESULTS: The incidence of livebirth was only 6% when day 14 to 16 hCG values were less than 100 mIU/mL, but increased to 82% with levels greater than 100 mIU/mL (P less than 0.001). The incidence of livebirth and multiple birth correlated with rising hCG levels. Only 1% (1/71) of pregnancies with serum hCG values greater than 100 mIU/mL was ectopic, and this case was a bilateral (double) ectopic.

CONCLUSIONS: A single serum hCG measurement obtained 14 to 16 days after embryo or gamete transfer not only is diagnostic but also has good predictive value for pregnancy outcome.

J Assist Reprod Genet 1995 Jan;12(1):13-4

Predictive value of hCG level 14 days after embryo transfer.

Guth B, Hudelson J, Higbie J, Solomon B, Polley S, Thomas S, Gentry WL

Advanced Fertility Institute, Methodist Hospital of Indiana, Inc., Indianapolis 46202, USA.

OBJECTIVE: It has been reported that the quantitative serum hCG level 14 days after embryo transfer (ET) correlated with pregnancy outcome as well as a likelihood of a multiple gestation pregnancy. This prospective study was designed to assess the predictive value of a 14-day post-ET hCG level with pregnancy outcome and multiple gestation pregnancies.

METHODS: Patients undergoing in vitro fertilization (IVF) and ET were monitored by serum quantitative hCG levels 14 days after ET. If positive, serial values of hCG were obtained and transvaginal ultrasound was performed 3 weeks after ET and weekly until fetal cardiac activity was seen. Ongoing pregnancies were defined as greater than 20 weeks.

RESULTS: One hundred eleven patients had positive serum quantitative hCG levels 14 days post-ET; 89/111, or 80.2%, had ongoing pregnancies. The spontaneous miscarriage rate was, therefore, 19.8% (22/111). If the level was less than 300, the ongoing multiple pregnancy rate was 9% (5/57). If the level was between 300 and 600, the ongoing [multiple] pregnancy rate was 40% (10/25). If the hCG level was greater than 600, the multiple pregnancy rate was 100% (7/7).

CONCLUSIONS: These data support the hypothesis that hCG levels greater than 200 mIU/ml on 14 days post-ET are more likely to have ongoing pregnancies; hCG levels greater than 600 have a high likelihood of a multiple gestation pregnancy.

HCG Level	Doubling Time
< 1200	48-72 hours
1200 to 6000	72-96 hours
> 6000	>96 hours

HCG Level	No. of Women	Ongoing Pregnancy
25-50	78	<35%
50-100	95	35-64%
100-200	159	64-80%
200-500	220	80-95%
500-1000	87	95-100%
>1000	23	100%

First HCG Level		mIU/mL
Second HCG Level		mIU/ml
Days Between Tests		days

Doubling Time		hours
Daily Rate