hCG Levels in Early Pregnancy

    1. What is hCG?

    2. How soon can I detect a pregnancy?

    3. What does my hCG level mean?

    4. Is my hCG level "normal"?

    5. hCG Level Chart by Week

    6. What does it mean if hCG is "slow rising"?

    What is hCG?

    hCG is the abbreviation for "Human Chorionic Gonadotropin," also known as the pregnancy hormone. This hormone is produced by the placenta as soon as implantation happens, about one week after fertilization and ovulation. hCG levels continue to rise after implantation until about 10-12 weeks gestation, at which point the hCG level will stabilize or drop.

    Pregnancy tests detect the amount of hCG in the blood or urine and a pregnancy test becomes positive when there are sufficient levels of hCG. Blood hCG testing is much more sensitive than urine hCG testing, therefore a blood hCG test can detect pregnancy several days before a urine pregnancy test.

    How soon can I detect a pregnancy? 

    A pregnancy is typically detected by a missed period and implantation bleeding, as well as through typical pregnancy symptoms and early positive pregnancy tests. You can help detect your pregnancy now by doing our online pregnancy test (OPT), and can calculate your hCG levels with the hCG Calculator.

    Most pregnancy tests and symptoms depend on high enough hCG levels - the higher the hCG level, the sooner you can detect the pregnancy with a test and the more symptoms you will have. A positive pregnancy test means that there is sufficient amount of hCG in your body. In blood hCg tests anything over 25 mIU/ml is considered enough evidence for as pregnancy, while urine pregnancy tests usually require a higher blood hCG level to be positive.

    What does my hCG level mean?

    • hCG under 5mIU/ml: Negative, not pregnant.
    • hCG between 5-25 mIU/ml: Uncertain; possible pregnancy but not definitive. Repeat test in a couple of days.
    • hCG over 25 mIU/ml: You are pregnant!

    The presence of a hCG blood level above 25 mIU/ml or a positive urine pregnancy test usually indicate that you are pregnant. However, if you received an hCG injection for fertility then the presence of hCG does not necessarily mean that you are pregnant. In most normal pregnancies with hCG levels below 1,200 mlU/ml, the blood hCG level usually increases by at least 60% every two days though occasionally even a rise below 60% can indicate a normal pregnancy.

    What does a single hCG value mean?

    A single hCG value above 25 mIU/ml means that you are pregnant. You cannot determine with enough certainty how far along you are or if the pregnancy is viable from a single hCG value. For each day and week of early pregnancies there is a very wide variation of "normal" hCG values which makes it impossible to determine from a signle value what it means exactly except to say that you are pregnant or that you are pregnant within a wide range of weeks and day.

    A single hCG level:

    • Does no necessarily tell you whether you have twins or a singleton
    • Does not tell you if the pregnancy is viable
    • Does not tell you exactly how far along you are

    Is my hCG level "normal"?

    There is really no single "normal" hCG level in early pregnancy and there is a very wide range of hCG values as pregnancy progresses.

    • An hCG level below 5 mIU/ml is considered not pregnant.
    • An hCG level above 25 mIU/ml is considered pregnant.
    • An hCG level between 5-25 mIU/ml requires a follow-up test to confirm the results.
    • At hCG levels in early pregnancy below 1,200 mIU/ml, the hCG usually doubles every 48-72 hours and it should normally increase by at least 60% every two days. 
    • Between 1,200 and 6,000 mIU/ml serum hCG levels in early pregnancy, the hCG usually takes 72-96 hours to double.
    • Above 6,000 mIU/ml, the hCG often takes over four or more days to double.
    • In general, when the HCG level reached 7200 mIU/ml, a yolk sac should be seen
    • At an HCG level greater than 12,000 mIU/ml there should be a  visible embryo with a heartbeat, though it could take up to an hCG level of 22,000 mIU/ml to first see the fetal heart beat.
    • After 9-10 weeks of the pregnancy hCG levels normally decrease.

    It makes little sense to follow the hCG level above 6,000 mIU/ml as the increase is normally slower at this point and not related to how well the pregnancy is progressing. After two to three months the hCG levels will slow even further and eventually hCG levels may even decline before reaching a plateau for the duration of the pregnancy.

    If you are interested in finding out if your pregnancy hCG level is progressing normally, it is important to find out whether your blood hCG level is rising normally or not. The chart below shows normal hCG levels. Click here for more hCG information.

    hCG Level Chart by Week

    Days from LMP

    Weeks
    from LMP

    Events Avg hCG
    mIU/ml
    Range hCG
    mIU/ml
    26 3w+5d   25 0-50
    27 3w+6d   50 25-100
    28 4w+0d Missed
    period
    75 50-100
    29 4w+1d   150 100-200
    30 4w+2d   300 200-400
    31 4w+3d   700 400-1,000
    32 4w+4d   1,710 1,050-2,800
    33 4w+5d   2,320 1,440-3,760
    34 4w+6d   3,100 1,940-4,980
    35 5w+0d   4,090 2,580-6,530
    36 5 1/7   5,340 3,400-8,450
    37 5 2/7   6,880 4,420-10,810
    38 5 3/7 yolk sac 8,770 5,680-13,660
    39 5 4/7 yolk sac 11,040 7,220-17,050
    40 5 5/7 yolk sac 13,730 9,050-21,040
    41 5 6/7 yolk sac 15,300 10,140-23,340
    42 6 heartbeat 16,870 11,230-25,640
    43 6 1/7 heartbeat 20,480 13,750-30,880
    44 6 2/7 heartbeat 24,560 16,650-36,750
    45 6 3/7 embryo seen 29,110 19,910-43,220
    46 6 4/7 embryo seen 34,100 25,530-50,210
    47 6 5/7 embryo seen 39,460 27,470-57,640
    48 6 6/7 embryo seen 45,120 31,700-65,380
    49 7   50,970 36,130-73,280
    50 7 1/7   56,900 40,700-81,150
    51 7 2/7   62,760 45,300-88,790
    52 7 3/7   68,390 49,810-95,990
    53 7 4/7   73,640 54,120-102,540
    54 7 5/7   78,350 58,200-108,230
    55 7 6/7   82,370 61,640-112,870
    56 8   85,560 64,600-116,310

    What does it mean if the hCG is "slow rising"?

    There are several possibilities when a Beta hCG level rises slower than expected:

    1. Sometimes a normal pregnancy can have a slower than expected hCG titer, and the next test will usually show a normal rise. It is quite possible to have a “slow to rise” hCG level and go on to have a normal pregnancy.
    2. Most commonly, a slower than expected rise indicates a pregnancy that may be failing, such as a miscarriage or a blighted ovum.
    3. Another possibility is an ectopic pregnancy, which is when the fertilized egg implants itself somewhere other than the uterus, such as the fallopian tube, cervix, or ovary. IVF increases the risk of ectopic pregnancy over natural conception.

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