Ming- I just looked this terminology up this last week. From the Bella Online website:

Chemical pregnancy… What is it? It is a term used for an early miscarriage. It is a pregnancy that has miscarried prior to the gestational sac becoming visible on an ultra sound. Pregnancies don’t show on an ultra sound until 5 or 6 weeks. At this point it is considered a “Clinical Pregnancy”. The names only refer to if they can or cannot see the sac with an ultra sound. Many doctors out there will tell you that it wasn’t real and it’s nothing to cry or grieve over. This is not true. A chemical pregnancy is a real pregnancy that was detected only by chemicals, not an ultrasound. It’s like that saying, “Just because you can’t see it doesn’t mean it’s not there”. So you got a positive pregnancy test… This means you did conceive! Pregnancy hormones just DON’T float around in your body and then “poof” they are gone. Pregnancy tests today are much more sensitive to the HCG hormone and can detect these early loses. Chemical pregnancies are unfortunately very common among woman. Around 50 to 60 percent of first pregnancies end in miscarriage, even without the woman knowing it.

Many of us have had chemical pg's. You may get a + test and still start your period. I'm not sure if that is what happened to me back in May, but I think it is. I had four +'s and ended up starting my period anyway. That's one of the reasons why we are always saying to wait to test until AF is due. HTH!

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