Posted by: Clarise | 2004/01/22

Size of fetus

After reading many books and other info on fetus development, all of them indicated that the fetus should be 35mm long at 8 weeks and 65 mm at 11 weeks. I had my first scan @ 8 weeks and the little one was only 20mm and at 11 weeks only 45mm...should I at all be concerned about this?

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Our expert says:
Expert ImageGynaeDoc

The correct figures are 45 mm at 11 weeks and 16 mm at 8 weeks, so your fetus is spot-on.

Best wishes

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Our users say:
Posted by: Purple | 2004/01/23

My gynae told me exactly what Kippie's said in her posting. My baby's measurements have all been head to rump, and he warned me that magazines give size as head to feet, so I shouldn't be alarmed if there are differences in size.

Reply to Purple
Posted by: www | 2004/01/22

It's very important to trust your doctor with things like this. It's very good to read up, but I don't think that you should be worried about something as significant as the size of the fetus if the doctor isn't worried about that - I'm sure that he/she would have mentioned if your baby is not developing normally. Kippie makes a lot of good points.

Reply to www
Posted by: Kippie | 2004/01/22

Hi there
Please keep in mind that some doctors measure head to rump and other doctors measure the complete baby. It could be that the shorter measurements were the head to rump,t herefore excluding the length of the legs and feet.
Different sites also states different measurements.

All babies are different - just look at the people around you how they differ. According to the books my baby was supposed to weigh 220grm at 18 weeks, and mine weighed 273grams - I am now 20 weeks. From 14 weeks onwards they do not measure the baby anymore seeing that it is too big for the screen, they go according to weight.

I am sure that all your babies are doing fine and that the doctors would have said something if it wasn't - so don't worry!!

Reply to Kippie
Posted by: Norma | 2004/01/22

I went for my 12week scan and baby was 59mm, my doc said baby is growing fine, so I'm not worried.
I think 45mm is fine, they do grow alot in one week.
Don't worry your doc would have said if something is wrong.

Reply to Norma
Posted by: Marlene | 2004/01/22


I'm 8weeks pregnant, went for my first scan at 7weeks and the baby was 7.1mm long. I'm totaly confused now!!!! On the internet sites it says something different. Now what is the right lenght at 8weeks. Should I be concerned now!!!!!!????


Reply to Marlene

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