What's causing moms to give birth to bigger babies?

Last week a Michigan mom gave birth to a baby who, even though premature--she came four weeks early--weighed 12 pounds, 3 ounces! Although Cristal Hebel's doctor said Baby Ayara set a personal record for her in her 21 years of practice, big babies like that are not as much a rarity as you'd think--especially when considering that a newborn is classified as having excessive weight if he or she weighs more than 8.8 pounds.

I personally think that means the majority of newborns are too big, but the fact is that according to a recent study, on average, infants are 100 grams heavier that they were 50 years ago. 


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This was certainly not the case with my children. My daughter weighed 6.8 lbs when she was born three days before my due date. She was tiny. I clearly remember my mom and my sister having to run out to get preemie clothes for her because everything I had was huge on her. My son, who was born two weeks earlier, was way bigger when he came out weighing 7.12 pounds. But considering what the babies of my friends weighed when they were born, it seems like mine were the exception.

According to doctors, excessive infant weight is directly attributed to maternal obesity and diabetes. But when those don't apply, it's really not known what's causing this phenomenon. Speculation points to the same things that are causing girls to go through puberty earlier: food contaminants or hormones in meats. Either way, doctors say the trend is worrisome because it's obviously harder for mom to deliver larger babies and excessive infant weight may be an indication of other medical issues for both mom and infant. 

Meanwhile, Baby Ayara has skipped the first two sizes of diapers and is already wearing a size 2. None of the clothes her parents got for her at their baby shower fit her, but she's at least doing well at the hospital's neonatal intensive care unit.

How much did your baby weight at birth? Did you worry about this while you were pregnant?

Image via MamaT/flickr