Why is There So Much Weight Gain During Pregnancy?

Where does all that weight you're gaining go? Learn why you need to pack on those pounds.
pregnancy weight gain

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You know you're going to be gaining some weight during pregnancy--but those 25 to 30 pounds doctors recommend seem pretty steep for that little 7-pound bundle of joy. It turns out that your little guy will account for only about 26 percent of your total weight gain. Here's where the rest of the weight gain will go, and why it's so important for it to be there.

4 pounds of increased fluid Your body is naturally filled with fluids--they keep your organs and cells hydrated, and they're used to help transport blood and nutrients all around your body. When you're pregnant, the amount of fluid increases to make the flow of nutrients even more efficient. This fluid is stored in tissue all over your body, and you can blame that excess fluid for the swollen ankles and feet you might experience in your last trimester.

4 pounds of blood Now that your heart is pumping for two, you need more oxygen-rich blood circulating throughout your body and to your baby. As your blood volume goes up, so does the number on the scale.

2 pounds to your boobs "The pregnancy hormones progesterone and human chorionic gonadotropin (hCG) cause milk ducts to activate and breast tissue to swell--possibly by as much as two cup sizes," says James E. Ferguson II, M.D., professor and department chair of obstetrics and gynecology at the University of Virginia School of Medicine. This is all to get those puppies ready to feed your little one when he arrives.

2 pounds to your uterus Home to your baby for the next 9 months, your uterus thickens, expands, and grows right along with that little bundle it's housing.

1.5 pounds for the placenta This special new organ is created by your body to nourish your baby the entire time she's inside of you. How incredible is that?

2 pounds of amniotic fluid Your baby floats around inside your uterus surrounded by amniotic fluid, which is made up of water, electrolytes, proteins, and other nutrients used to aid in his growth. Like a liquid hug, this fluid keeps your baby warm, and protects him from jostling around inside your body.

7 pounds go into storage As your pregnancy progresses, you can expect to see more junk in your trunk--literally, in your rear end and around your hips and thighs. While that baby gets bigger in your uterus, your body goes into storage mode, creating deposits of fat, protein, and other nutrients that will be used to help you make breast milk when the baby arrives, says Kathleen M. Rasmussen, Sc.D., R.D., professor of nutritional sciences at Cornell University and chair of the committee on Weight Gain During Pregnancy: Reexamining the Guidelines at the Institute of Medicine.

7.5 pounds (or so) is your baby And lady, you'll be surprised by how heavy that little one feels in your arms when she finally arrives -- enjoy it!

Copyright © 2014 Meredith Corporation.

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