Talk

Flip

Get updates on how your baby develops, your body changes, and what you can expect during each week of your pregnancy by signing up to the Mumsnet Pregnancy Newsletters.

Pregnancy

How reliable are scans for measuring baby's size/weight?

15 replies

Sappholit · 10/02/2010 15:51

I wonder if anyone here can help me.

I'm 38 weeks now and due to give birth by c-section next Friday.

I have, and always have had, a very small bump. I barely looked pregnant at six months, and have still only gained a stone. I prob look 5/6 months pregnant.

At my 33-week antenatal appointment, my bump was only measuring 29cms. I'd had a scan the day before to check the placenta, and the notes said the baby was a good, average size, with an estimated weight at that point in time of 4lbs 1oz. My midwife wasn't very worried, and when I went back 2 weeks later, bump was measuring 32cms, whihc she said was fine as it meant baby was definitely growing.

I then had to have another scan at 37 weeks, again to check the placenta. The photographer (or whatever they're called) took one look at me and told me I was too small, but she took measurements of the baby and they were all fine. She also measured the fluid, which was fine, and did a doppler scan to check the bloodflow from the placenta. This was also fine. Baby's weight then was 6lbs 1oz, so she had grown exactly 2lbs in four weeks, which seemed right on target.

The next day, I wnet back to the midwife, who I hadn't seen before, and she was very worried about my bump. It was only measuring 29cms, so in theory, it was shrinking. She kept looking at the scan notes and shakign her head, in a 'This is impossible' kind of a way.

I keep looking at my bump and fretting. It is undeniably very small. But so am I. Everyone comments on it, and some people - strangers - even tell me I need to get it checked out.

I am getting really nervous now that the baby is tiny and should have been delivered already or something. But she is definitely alive and kicking, because I can feel it. Also, her movements seem to be getting bigger.

But I am still very worried. Has anyone else experienced this and had a normal-sized baby?

OP posts:

Report

Ziggurat · 10/02/2010 16:19

Scan and fundal height measurements are notoriously inaccurate.

I would say please don't worry (and they are wrong to be worrying you so), but I know it's easier said than done.

Fundal height measurement is pre-historic IMO, and I can't believe they still do it. The size of your bump depends on many things - your own size, where the baby is positioned, how strong your tummy muscles are, etc, etc.

I had the opposite problem - a massive bump, big fundal height measurements (I was measuring one month ahead at one point), the extra scans they made me have were showing a big baby, and I was sent for the glucose test to ensure I didn't have gestational diabetes.

Now I'm 5'9" and DH is 6'3" so we were never going to have a small baby. Luckily I'm not the worrying type, or I'm sure they'd have all driven me round the bend!

As it was, DS1 arrived, weighing only 6lb 13 oz - not huge by any stretch. But - I did have massive amounts of amniotic fluid, which was what made my bump so big.

On another forum that I post on, a girl got to 32 weeks without even knowing she was pregnant - she went into the hospital in size 8 clothing at this point, and this was when they discovered she was pregnant. You hear these stories and don't really believe them, but this is true!

Honestly - scans and measurements are so, so inaccurate and such a massive cause for worry. Your baby is just tucked in nicely, and you clearly have fabulously developed tummy muscles to hold him/her in place.

I have heard of people with teeny, tiny bumps, being made to worry all along, and then popping out a massive 9 pounder!

All will be just fine.