When you find out that you're expecting a child, how much do you have to alter your diet and exercise routine and how does it benefit the pregnancy?

In part two of our three part series on pregnancy and baby life, we examine how to put together the proper exercise plan.

Dr. Susan Passarella, an M.D., OB-GYN and Hospitalist with Hackensack Meridian Healthcare, says women who exercise while pregnant are healthier and have better deliveries.

She says activities like running, zumba, yoga and swimming are great to do while pregnant.

"The American College of OB-GYN recommends about 150-minutes of exercise per week for patients and you can split that up into 30-minute increments five times a week or you can break it up into even smaller ones," Dr. Passarella said. "A long time ago they used to look at a heart rate and didn't want a mom's heart rate to go over 120 and what we found is that doesn't really make a difference, it's really what your baseline heart rate is."

Dr. Passarella says it's important to build up endurance during a pregnancy to make things easier during labor and delivery.

"Anything that gets your heart rate up is going to help," Dr. Passarella said. "When you're pushing in labor your heart rate is going to go up so it's going to be similar to that and it'll give you more endurance."

You should stay away from contact sports like rugby, soccer, sky diving and water skiing while pregnant.

"The uterus is very protective of the baby but you don't want to take part in any big, high energy sports," Dr. Passarella said.

Having a good diet during a pregnancy is important for you and the baby.

Dr. Passarella says women need to add an additional 300 calories to their diet but weight gain is unique to the individual.

"It really depends what your pre-pregnancy weight is, that's what we look at," Dr. Passarella said. "If you're an average weight we expect someone to gain between 25-35 pounds. During the first trimester people are usually nauseous and sick and they tend not to gain a ton of weight but it tends to catch up to them in the last month where you can gain a half-a-pound to a pound a week."

However, it's not recommended to buy into the "I'm eating for two" diet.

"I know everyone always says when you're pregnant you can eat for two but that's not necessarily what we recommend because then you'll have patients gaining 50, 60, 70 pounds and those patients tend to have more complicated deliveries, they're at a higher risk for diabetes and hypertension and are more likely to have c-sections or have babies that are really small and may not grow as well," Dr. Passarella said.

Do you have to change what and how you eat while pregnant?

Dr. Passarella says you should always wash fruits and vegetables before consuming and meat should be cooked well done, fish is ok but only with low mercury, listeria which is found in certain foods, is definitely a concern.

"We worry about different bacteria's in pregnancies, you do have a mom and a baby and if that baby is exposed to a bacteria that can potentially get in utero that can cause really harmful affects to the baby," Dr. Passarella said.

It's not known how much alcohol causes fetal alcohol syndrome so doctors say don't drink any amount, smoking leads to smaller babies and pre-term labor, caffeine is fine but limit it to 300 milligrams a day.

On the flip side, you should drink 10-12 glasses of water a day to prevent dehydration and pre-term contractions.

One of the biggest misinterpretations associated with pregnancy is heartburn and what it means.

Dr. Joanne Chang, an OBGYN with Hackensack Meridian Healthcare says the belief that a lot of heartburn leads to your baby being born with a lot of hair is an old wives tale with no study's to back that up.

"There's no studies that have shown that what you eat affects how much hair your baby has," Dr. Chang said. "You hear anecdotally that women will say 'oh, I had so much heartburn and my baby had so much hair' but on the flip side you'll talk to women who will say 'I had a ton of heartburn and my baby had no hair'."

Dr. Chang says heartburn is a normal part of the pregnancy due to the hormonal changes as well as the baby pushing your stomach which pushes everything up and causes acid-reflux in the esophagus.

"Heartburn is very normal during pregnancy. It's one of the side effects of the hormone changes and from physical space. As the baby grows bigger it pushes up on everything and makes the acid reflux a little bit into your esophagus," Dr. Chang said.

In part three of our series tomorrow a Jersey Shore mom of five children, including her first son that was born over the summer, gives her point of view on what pregnancy is like and how to be a good parent.

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