What determines how heavy your baby is at birth?

[turquoise88]

I mean, aside from babies who are born very early and obviously small(er).

There probably isn't a definitive answer but it got me thinking. The last three women I've known to give birth are all what I would deem to be slim build (size 8/10) and have had big babies (9lb +).

I know some curvier women with higher BMIs and almost all have given birth to babies between 5lb and 7.5lb.

Is it weird to assume there would be a correlation between the weight of a mother and the weight of a baby?

I don't really know what the point of this thread is, other than I'm interested!

maternal not material!

Interesting about placental function as I had twin boys who were 7lb 1oz and 5lb 15oz. I was told the placentas were fused while I was pregnant. The lighter twin was 10 cm longer than the heavier one and was like a skinned rabbit at birth, as opposed to the Michelin man his brother resembled!

He is now 6ft4 at 16 while his brother is only 5ft10.

His paediatrician suggested that his low birthweight compared to his length indicated he didn't get enough nutrients in the womb and may be the reason he has severe learning difficulties. This thread has reminded me to request my pregnancy notes to see if anything was noted about the placentas so thanks!

No idea but Kate Middleton always has large babies and she is tiny. Am guessing it is a healthy diet and genetics.
I guess if you are very overweight this might impact too.
Interesting question.

Mine were 9lb and 10 4. I was sick with both of them, didn't gain any baby weight with no 2.

I am big boned, broad, and was a little overweight.

Genetics, placental function and mothers blood sugar / bmi also plays a part

Mine got smaller.

7lb 8oz
6lb 12oz
5lb 11oz

(The 3rd was 38 weeks but others 41 weeks and 40 weeks respectively)

I was heaviest when I got pregnant with DC3.

Oh and I had gestational diabetes with DC3. Managed with diet and medication from 29 weeks.

I had sections with all of mine (10lb 12, 11lb 13 & 8lb 12). After the birth of my first they specifically told me that if I had anymore I needed to tell them about the size of my placenta as there was an increased risk of bleeding. I remember them bringing the placenta back to recovery to show my mum too!

I'm a slim size 10 and had a 5lb 8oz baby. My placenta is lazy.

My sister and I were 10.5lbers. DS was 10lb5.

I think genetics plays a large part.

I am only 5ft4 but always look massive when I am pregnant. I think it's down to diet and exercise to be honest. My first was 8lb 12 oz and I ate loads of junk food and drank full fat coke throughout, my second was 7lb 10oz and I suffered with sickness and didn't eat as much junk/ drank diet lemonade. My 3rd weighed 6lb 8oz and I ate relatively healthy throughout and drank flavoured water, I was also a lot busier with work and hardly ever stopped with having two older children x

I had a 10lb+ baby. I am 5ft 3, DH is a whole foot taller. The 10 pounder takes after him and the other 2 take after me (6.4lbs and 7lbs, small frames)

must be a big element of genetics.
dc was born in a london hospital with a large local asian population.
dc was a tiny (for my family) 7 pounds but many of the asian babies were a bit over half that.

I'm interested in this question. In my case, it all seemed to be placental function. I was size 8/10 and had been a small baby myself, below 6lb. DH was a very small baby but he was born prematurely so it's hard to say what he would have weighed at term. Both of us are average height.

I put on quite a lot of weight with DD1 but not an excessive amount. I had a really small bump so I didn't watch what I ate too much. Baby was born a few days after term at 9lb8. Second DD I was more aware of what I ate and stuck to a healthy diet. I made sure I didn't "eat for two". She was still over 9lbs.

Fast forward several years and they are both slim and small-build.

Is it hereditary? As in if your mother had small/larger babies would you have the same?

Is it hereditary? As in if your mother had small/larger babies would you have the same?

That's practically what my consultant said. I was quiet far on and had just had a late scan, I asked about the size of baby. He said "ultrasound isn't that great at determining size, the best guide to the size of babies you'll have is the size of babies your mother had".

My babies all weighed between 7lb and 7lb 15oz even though I only put on half a stone with each of them because of morning sickness hyperemesis. I'm five foot nothing and small build so think they were as big as they could be tbh. My sisters who are all a lot taller than I am had babies weighing between 8 and 10lb and each put on a lot more weight and had none of the sickness.
I thought it was down to size of mums and weight gain in pregnancy tbh.

I was a size 8 with my first and had morning sickness, second baby I was size 16 and no morning sickness (just a bit of a queasy feeling) both babies were a good size (9lb 4.5oz and 9lb 9.5oz respectively). I'm only average height (5'6") and husband is 6'2" so I would guess maternal weight doesn't have much bearing.

Interesting that consultant thinks it's down to the mothers, mothers size of babies.
My ds was 8lb12oz, I'm only 5"4, DH 5"10.
I was 7lb something at birth as was my brother.
DH on the other hand was a whopping 9lb10 and MIL was 8lb12oz too when she was born. Surely the genetics come from both sides?

I have read that birth weight has a correlation with size of mother and final size has more correlation with size of both parents ie women generally don't give birth to babies too big for them even if the Dad is massive.
I imagine it's maybe head circ at birth rather than weight since that's the main factor in determining whether baby will fit through pelvis. If you think about it from an evolution POV, before birth interventions were so successful and accessible only women able to birth babies would have been positively selected.

Something lie that - it's late here!

I'm predicted a big baby and i am ALL bump, from behind you'd had no clue i was pregnant and look like i've had a football shoved up my top! Was also super sick for 7 months so barely kept any food down. I've been told to expect a BIG baby..

I'm 5ft 6

Mine were 6 15, 7 7, and 9 7.
I thought the last was due to undiagnosed gestational diabetes. But at 10 years old she is 5'4. I am 5'1

Im small and had 2 babies born 37 weeks at 2.3 & 2.4 kilos. So very small but i ate very healthily. Im small but not tiny and right now my kids (teens) seem if anything bigger than average so i wondered that. My feet are size 38

I'm predicted a big baby and i am ALL bump,

This would seem to make sense, but in my experience, I had a small bump all through pregnancy and big babies!

I also have quite small feet (size 5) for my height (5'7) so it would be interesting to know if that actually has any bearing on pelvis size. It was certainly hard work delivering my two....

DH was a big baby and my two brothers were both big. I was average. DS was just over 10 lbs at almost 42 weeks. Apparently his placenta was almost a kilogram! I think it’s genetics plus maternal diet and wellbeing to a lesser extent.