What Does Your Baby’s Weight Mean?

Does size matter? The year 2013’s biggest baby (so far) in the U.S. was just announced as “little” J.J. Brandon, Jr. of Orem, Utah, who tipped the scales at 14 pounds even. (A U.K. newborn beat that at 15 pounds, 7 ounces.)

I remember when my nephew, Bryson, entered the world at 10 pounds even. My brother crowed he was “the king of the nursery!” He was quieter 20 months later, when Bryson’s sister Paulina arrived weighing 10 pounds and a few ounces. What did it mean to have such a big girl — or boy? Would they stay big?

1. How big is big?

“High birth weight” babies are considered to be those who weigh more than 8 pounds, 8 ounces at birth (or 8 pounds, 13 ounces by some measures).

2. How many babies are we talking about?

About one in 10 newborns are considered macrosomic. (Translation: “large bodied.”)

3. Why are some babies big?

Gestational diabetes or a diabetic mom is the top factor in producing big babies. (That 14-pounder’s mom had type-1 diabetes.) Parent height and weight play a role, too. With some, it’s just a mystery.

4. Is bigger better? Worse?

High birthweight babies have a higher risk of birth complications  — more are delivered by C-section — and jaundice. After you clear those hurdles, there’s a risk of blood sugar problems in some, and a risk for obesity later in life. But most big babies are fine. Doctors are more worried about low birth weight babies (those under 5.5 pounds, usually preemies).

5. So will J.J. be a giant?

Not necessarily. Obesity is connected to other factors, especially lifestyle. J.J. might just grow up. My brother and his wife had four more kids after Bryson and Paulina, and all six cleared the 10-pound mark. (They weren’t all C-sections, either. My SIL is a champ!) All six outgrew the chubby cheeks by preschool. There’s not a hefty kid in the bunch now, though they’re trending tall and lean, like both parents. Paulina, that ex-“queen of the nursery,” is a gorgeous six-foot teenager with thighs like pencils!

All of which is to say that birthweight is no crystal ball. Most full-term babies log in at 5.5 to 9 pounds, just right for those newborn-sized clothes that last the blink of an eye.