Baby measuring a week+ behind?

I had a sono today and the dr said baby looked good. As he was measuring the baby i noticed on the screen that it said 16 weeks 5 days when really im 18 weeks 1 day. A few months ago he told me that i was 2 days behind and he moved my due date by 2 days but never a week. I didnt get to ask him about it cause we started talking about something else and then someone needed him in another room. I went to my Peri last week and she didnt say anything about it either, just said baby looks great. Is this normal? iI have my level II in 2 weeks so i guess i'll find out then. I was thinking maybe he didnt say anything cause my blood pressure is high enough and doesnt want to get me worried.

Re: Baby measuring a week+ behind?

at my " 20 week" sono - i was technically 21 weeks 2 days, however the baby measured 20 weeks 3 days... which it has been since my first sono - the sono tech said to go by the size of the baby, the Dr. said since it's only 6 days not 7 she is sticking with my original date.

Message edited 2/5/2010 1:51:18 PM.

Re: Baby measuring a week+ behind?

I was a week behind at my 12 weeks sono, I spoke to my OB and he didnt change my date. He said they go by the early sonos for the EDD and after that there is too big of a difference in sizes for each baby.

Re: Baby measuring a week+ behind?

It may be that your cycle is longer than the average that they go by when they are determining your due date. My cycles are irregular, sometimes even 40 days in length. I know I ovulated a week later than the usual 14 days, so on the ultrasound, the baby always measures a week behind (than what they measure on their standard due date scale). I think as long as the sonogram/ultrasound stats are consistent, it really isn't anything to worry about.

Re: Baby measuring a week+ behind?

They don't change your date. My DS measured behind too, he was born at 39wks weighing 6lbs, 11oz

Re: Baby measuring a week+ behind?

All babies grow at different rates. There were times I was 4 days behind with DS, and sometimes a week ahead.

Re: Baby measuring a week+ behind?

mine was a week behind in the beginning and then at my 20w i was 20w2d and was measuring 19w6d. They will grew some even grew like weeks ahead of schedule too.