Choosing a Sensitive Pregnancy Test

Pregnancy tests on the market today can vary in how early they can detect the pregnancy hormone, hCG (Human Chorionic Gonadotropin).

In the chart below, the smaller the number in the "hCG Detected" column is, the earlier you can use the pregnancy test. As a general rule, hCG levels, if you are pregnant, are between 5 - 50 mIU a week before your period is due. The hCG levels in your system should double every two to three days.

Detection of pregnancy depends on the sensitivity of the pregnancy test AND how your system is creating the hCG. hCG is created by your uterine lining once the fertilized egg has implanted. Every woman is different and the time it takes for the fertilized egg to implant in your uterine wall can vary. Research show implantation typically occurs 6-12 days after ovulation, with 84% of the pregnancies implanting on days 8-10 after ovulation.

If a negative pregnancy test, it doesn't mean that you are not pregnant. It could be that you ovulated later than you thought (meaning that conception and subsequent hCG production didn't happen as when you expected) or that, for you, implantation took longer than the average. Your period arriving is a sign that you are not pregnant this cycle, as is a negative blood test from your doctor.

Should I Use The Most Sensitive Pregnancy Test?

For most women, the resounding answer would be YES! It allows you to know as early as possible if your attempts to conceive were successful. There *is* a downside to extra sensitive pregnancy tests though. Unfortunately, 25% of all pregnancies end in miscarriage. If you use a very sensitive pregnancy test, where you test before the day your period is due, you could catch an early pregnancy but end up going on to have your period anyway, due to a very early miscarriage. Some women will find it very hard to deal with this sort of emotional roller coaster.