I'm a little confused.

I am 38 weeks and 4 days pregnant tomorrow according to my doctor and ultrasounds and all that throughout my prenatal visits. My question is this. When i first found out i was pregnant, the ultrasound put me a whole week before i even started my last period. When i came on my last period it seemed pretty regular to me, but i didn't know i was pregnant til a month later when i clearly missed. How could i be pregnant before i came on my period and still get a period but had no symptons until about a week after i found out i was pregnant. I was going on 13 weeks before i knew i was pregnant. Any answers?

[Diane1003]

Maybe you ovulate early in your cycle.  I think most dating like that is assuming you ovulate at about CD 14 - not everyone meets that mold!  

[christal28]

some women have periods even when they are pregnant my sister is one of those she has two kids and the first clue was weight gain and sore breasts, she had a period until she was 6 months pregnant with both. it surprised her both times!!

[njeosys]

christal28 is right. Some women don't miss their period when they first get period, which suggests you may have ovulated closer to your expected period than you thought. Congrats on the baby!!! They'll be here soon!

[alaysha]

By thirteen weeks babies start developing at their own rate and ultrasounds are often off by a week. I wouldn't be too concerned.