Why was my baby so big?

[expatmommy]

I recently gave birth to my 5th child. My previous living children were born 12, 11 & 16 days overdue and weighed 8lb 1oz, 7lb 10oz, & 8lb respectively. None of them had placentas that looked overdue. I figure I'm just a long gestator.

My most recent child was overdue 16 days by dates & 12 days by early u/s. I had another u/s at 36 weeks and she was estimated to be 6+ lbs at that point (which I know is just a big guesstimate anyways). She was 10lb 3oz at birth!!

When I asked my doctor today why she thought my latest child was so substantially larger then my other children, she thought there was 2 possible explanations: 1) this baby is just on a different scale then the others and her size is essentially a fluke, or 2) undiagnosed gestational diabetes. She said if I were to get pregnant again, she would recommend a 2nd GD test in the middle of my 3rd trimester.

With this pregnancy, I took a significant amount of folic acid & B vits as well as baby aspirin for the first 1/2 of the pregnancy. I also exercised significantly more then I ever have before when pregnant. I specifically focused on eating food that would support good blood flow & placental growth. I have no idea if any of these things made a difference in the size of my baby.

We aren't likely having anymore babies, but I do admit a bit of anxiety that I might have an even bigger baby if we did. This birth did things to my lady parts that will take a long time to heal, partially due to her size & presentation & speed of arrival.

So, any thoughts on why the 2lb 2oz jump in size between my kids?

[Viola]

Was she significantly longer than your other children? I had a 2 lb jump between my first and second child, and I really wasn't expecting it at all, I was thinking she would be smaller. But she was also 3" longer, so I'm sure that made a difference.

[Amynf1]

My baby wasn't as big as yours, she was 'only' 9lbs 3oz but that is a full lb more than my first. I ate really poorly in my first pregnancy and was basically unhealthy altogether. In this pregnancy, I exercised, ate a whole foods diet, took fish oil and organic prenatals, drank nutritious teas and bam...bigger baby. They both had 15 inch heads though so I guess the body size point is moot.

[GoBecGo]

Have you developed endometriosis since your last baby? My friend recently had her first, who was 10lbs11oz and her MW said she's found women with endo which is bad but not so bad they can't conceive have bigger babies, possible due to a bigger placenta, possibly due to extra oestrogen. Possible for you?

Also, how much did your placenta weigh? Was it also bigger? Maybe taking aspirin made a difference in vascular structure which made a difference to her eventual size?

[cappuccinosmom]

My youngest was 10 lb 8 oz. I have never, ever tested pos. for gestational diabetes (nor had any other complications). I was tested for diabetes again recently (because I cannot lose weight, among other things) and am perfectly normal in that regard.

However, I have other things that seem to be related to blood sugar issues, so I wonder if there might have been a similar dynamic that grew my last two babies big. They were both also 16 days overdue, funnily enough.

[expatmommy]

Originally Posted by GoBecGo

Have you developed endometriosis since your last baby? My friend recently had her first, who was 10lbs11oz and her MW said she's found women with endo which is bad but not so bad they can't conceive have bigger babies, possible due to a bigger placenta, possibly due to extra oestrogen. Possible for you?

Also, how much did your placenta weigh? Was it also bigger? Maybe taking aspirin made a difference in vascular structure which made a difference to her eventual size?

Hmm, no endo that I know of.

My placenta was normal according to my doc. It didn't look any different then my previous ones & didn't look overdue at all.

[loveneverfails]

I found that for me, high protein in the 1st trimester made my babies jump up 2 lbs bigger roughly. And I pass the glucose challenge every time.

[MegBoz]

Originally Posted by expatmommy

I also exercised significantly more then I ever have before when pregnant.

Well, did you continue to exercise all through the pregnancy?
I remember reading in the fascinating book, "Exercising Through your Pregnancy" by Dr. Clapp that women who exercised had the smallest babies of all. ("Exercise" being defined as 3X per week or more, 20 min or more, at "moderate to high intensity" so walking wouldn't count unless it was really speed/hill walking.)

HOWEVER - the biggest babies of all were born to those who exercised early on, then stopped.

He theorized that the exercising built a larger/more efficient (?) placenta to ensure the fetus would get nutrients, blood & oxygen while mama is exercising (since blood gets diverted to the working muscles while mama exercises.) So exercising at first, then stopping grew the largest babies of all 3 groups (stopped exercising, continued exercising, healthy but not exercising).

(Also note, this is "large" babies based purely on weight - the babies of exercising mamas had comparable head circumference to those of non-exercising mamas, but smaller 'waist sizes' - literally, they were leaner & had lower body fat! I'm a fitness instructor & kept up teaching cardio kickboxing, step aerobics, & weight lifting, the whole way through. I showed DH the photos from the book after DS was born & he exclaimed, "Yeah, DS looks JUST LIKE THAT!" With his little skinny chicken legs at 7# 4 oz. Hehe - but he caught up quickly.

[Viola]

Originally Posted by MegBoz

Well, did you continue to exercise all through the pregnancy?
I remember reading in the fascinating book, "Exercising Through your Pregnancy" by Dr. Clapp that women who exercised had the smallest babies of all. ("Exercise" being defined as 3X per week or more, 20 min or more, at "moderate to high intensity" so walking wouldn't count unless it was really speed/hill walking.)

HOWEVER - the biggest babies of all were born to those who exercised early on, then stopped.

That's interesting. In my first pregnancy, I exercised but quit in the third trimester. Then I gained so much water weight and started having problems with constipation, so I started exercising again in the last week or so. My exercise was basically walking outside (up and down hills) or on the treadmill, and stretching. I had a 9lb 5oz baby.

So with my second pregnancy, I felt like I ate less and exercised more, I gained less weight, only 11 lbs. I did weight training, and also walked fairly strenuously or did aerobics videos. My heart rate didn't go up as high in my second pregnancy as it did in my first. Basically in my first I couldn't keep it under 140, there were times when it went way above that and I felt fine, so I stopped worrying about it after talking to my doctor. In my second pregnancy, I was in better shape going in, although I did weigh more, and it didn't go up as high, although it was in the aerobic/cardio range, usually under 150, though. I think I stopped doing the weights for the most part at some point, as I got farther along and much bigger, but I still did things like lunges and squats. I carried my 4 year old around and was active right up until the end, but maybe I cut down on how hard I was exercising. I was measuring right on target for my weeks until about 40 weeks where I jumped up 10 cm. And ended up with an 11-6, 23.5" baby, so I'm not sure what happened. I was thinking she'd be smaller, because I had heard that about pregnancy and exercise. I didn't have the huge water gain and swelling, though, which was nice.

I don't know about head size, though, because they never told me what my first daughter's head measured at birth, and she had a lot of molding and swelling and looked huge, but was only 14" a week later. My second daughter had relatively little molding and her head was 15". When I first saw her, I said she looked like a pinhead, but clearly her head size was fine, it's just that her chest was 14.5" too, so in comparison her head seemed smaller. My first daughter has always had a big head though.

I did eat a lot of protein in the first trimester. I always wonder what is at work.

[loveneverfails]

Here is my theory, and obviously I am not a doctor, insert disclaimer HERE:

I think that some people are naturally more disposed or less disposed towards supporting a growing placenta in terms of their hormone levels (more estrogen favoring more aggressive placental growth.) I've heard a lot of people say that 1st trimester nutrition is for the placenta mainly and 3rd trimester nutrition is for the baby.

I believe that if you have hormone levels that dispose towards strong placental growth and then follow a regimen to promote a "strong and healthy placenta" you are essentially pouring miracle grow on it, and the result may be a macrosomic infant. For people who tend to grow too small babies or have preterm labor, it might be a really good idea to protein load. But I think there really is such a thing as too much of a good thing.

And I did find an animal study showing that placental overgrowth preceded fetal overgrowth, so the placenta (in my opinion) may be the key to when women without gestatational diabetes wind up with very large infants who truly can be "too big" to safely give birth to vaginally.

Bottom line is that I know that before I started high protein diets like Brewer, I had babies around the 8 lb mark. Following Brewer half way, I had a 10 lb 2 ozer. Thinking I must have had GD that pregnancy and wanting to avoid another macrosomic infant, I protein loaded and the only sugars I ate were whole grains and fruits and veggies. 11 lbs even, and a week earlier than Miss 10 lbs 2oz.

So, baby #5, I went back to a normal diet with relying mainly on good carbs and limiting protein in 1st trimester, and I had a smaller baby. She had fluid overload from unrelated issues, but we feel like without the fluid overload, she would have been about 8 1/2 lbs at almost 42 weeks.

Sorry for the novel, but that's what my experience has been, and why I will not ever be protein loading again during pregnancy. My giant infants also had giant placentas, and it cause serious bleeding for me because with a wound site that big? You are going to bleed.

[kittywitty]

I would say diet and fluke. My mom had me 2 weeks overdue at 6lbs plus a few ounces. My youngest brother was almost 9 lbs, I believe.

[expatmommy]

Hmm, the exercise & protein ideas are interesting.

I exercised more earlier in my pregnancy, but did exercise right up to 36 weeks. I was running/lifting weights/stretching 3-4x wk for 45min each time.

I didn't protein load this pregnancy. If anything, I ate more leafy greens & other veggies then I ever have before. In my final weeks of pregnancy, I did have more protein then normal, giving in to cravings as I waited out my eternal pregnancy!

My dd's head was 13.75", so not huge. She doesn't look big or chunky at all. She is just on a totally different scale.

[Adamsmama]

I had an almost 2 pound jump between DS1 and DS2 and the difference is -- I didn't have MS during the 1st trimester with baby2 ... so I ate a lot ... including tons of fat and protein. Then in the 2nd and 3rd trimester I was a total sugar addict (I mean chocolate or cookies and milk at EVERY SNACK ... or so it seems). He was huge ... longer, fatter ... he looked like a 2 month old. Baby number 3 I had worse MS -- so less food in the first trimester and I ate regular smaller portions during the 2nd and 3rd trimesters ... I did eat a lot of carbs (more than protein) and baby was more of the size as DS1 -- just a little bit bigger than he was. This time I ate tons of protein during the 1st trimester and actually was on a lower carb diet ... now my carbs are higher but not nearly like with DS2.

[BetsyS]

For me, baby number 2 was significantly smaller than the other 2. I exercised pretty regularly with him, but that's the only difference.

With #1, I ate an awful diet (horrid morning sickness, losing 15 lbs in the first trimester; I was just happy something stayed down). I protein loaded (ala Brewster) in the 3rd trimester with him.

With #2, I ate well and exercised regularly.

With #3, I ate well. Not so regular about the exercise.

Mine were (and all 3 were boys):
#1--11 lb, 14 oz
#2--9 lb, 7 z (over 2 pounds smaller--he was a tiny little thing!)
#3--11 lb, 1 oz

So, really, I figure that while diet and exercise have some impact, sometimes it's just random.

[finnegansmom]

Maybe genetics?
My first was 8#1 and is much smaller boned/framed than my second.
My second was 9#10 and is stocky and big boned. We had shoulder dystocia with him, and a big head to boot. But, he has MY frame (poor kid). I'm bigger boned, big head, the works (poor me). But my first son takes after more of my husband's frame. Normal.

I don't have GD, and they did test my son when he was born since he was bigger and he was fine too. I did have a lot of stress with my first, so maybe he would have been "fatter" but I think some babies just have bigger structures than others...