Confirming pregnancy

After you conceive (when the sperm fertilises the egg), the developing placenta begins to produce and release hCG.

It takes about 2 weeks for your hCG levels to be high enough to be detected in your urine using a home pregnancy test.

A positive home test result is almost certainly correct, but a negative result is less reliable.

If you do a pregnancy test on the first day of your missed period, and it’s negative, wait about a week. If you still think you might be pregnant, do the test again or see your doctor.

hCG blood levels

Low levels of hCG may be detected in your blood around 8 to 11 days after conception. hCG levels are highest towards the end of the first trimester, then gradually decline over the rest of your pregnancy.

The average levels of hCG in a pregnant woman’s blood are:

• non-pregnant women - less than 10 U/L
• borderline pregnancy result - 10 to 25 U/L
• positive pregnancy test  - more than 25 U/L
• pregnant women, about 4 weeks after the last menstrual period or LMP (average 1 week before first missed period) - 0 to 750 U/L
• pregnant women, about 5 weeks after the LMP (week after first missed period) - 200 to 7,000 U/L
• pregnant women, about 6 weeks after the LMP - 200 to 32,000 U/L
• pregnant women, about 7th weeks after the LMP - 3,000 to 160,000 U/L
• pregnant women, about 8 to 12 weeks after the LMP - 32,000 to 210,000 U/L
• pregnant women, about 13 to 16 weeks after the LMP - 9,000 to 210,000 U/L
• pregnant women, about 16 to 29 weeks after the LMP - 1,400 to 53,000 U/L
• pregnant women, about 29 to 41 weeks after the LMP - 940 to 60,000 U/L

The amount of hCG in your blood can give some information about your pregnancy and the health of your baby. For example hCG levels can indicate:

• the presence of multiple pregnancies (for example, twins and triplets) – hCG levels are usually much higher when there is more than one fetus
• a loss of pregnancy (miscarriage) or risk of miscarriage
• an ectopic pregnancy – where the fertilised egg implants in the fallopian tube
• problems with the growth or development of the baby
• abnormal tissue growth in the ovaries or uterus, including some types of cancer in women who are not pregnant.

Levels of hCG in your blood don’t provide a diagnosis of anything. They can only suggest that there are issues to look into.

If you have any concerns about your hCG levels, or wish to know more, speak to your doctor or maternity healthcare professional. You can also call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436.