A reader asks: Now that I am pregnant, how do I keep my backside, thighs and stomach from getting fat and out of shape? Also, what is the best way to get back into shape after my pregnancy?

This is a question that goes through every mom’s head – whether pregnant, pregnant-to-be or pregnant in the past. This is also a great question for me, because I am in my fourth month of pregnancy and have been very conscious of healthy weight gain and maintaining a proper fitness level.

During this miraculous time of your life there are three basic principles to follow.

1. Healthy Eating. “Eating for two” is a saying that seems to cause a lot of problems. It’s almost like saying you can eat double, now that you are pregnant. Watch out, because this is where many moms take a wrong turn.

To keep your weight gain within the recommended guidelines (25 to 35 pounds), you only need about 200 extra calories per day (equivalent to one large apple). As long as you follow these next few rules, your baby is sure to get exactly what it needs for proper growth and development.

It is very important for you and your baby to make sure the intrauterine home is pure and healthy. There are five essential pregnancy nutrients, and you need to build a daily balanced diet around them. They include calcium, complex carbohydrates, good fats, iron and protein. Taking supplements/prenatals does not replace eating a nutritionally-powerful array of foods, but it does ensure that your balance of nutrients is correct.

So, step one in maintaining your pre-pregnancy body is eating naturally colorful, unprocessed, organic foods, free of hormones and pesticides, and taking your prenatal vitamins. Since supplements are not FDA regulated, it is up to you to make sure they have the right amounts of everything your baby needs. The most common lacking supplements are calcium, omega 3s, choline (fetal memory development) and vitamin D. Talk to your nutritionist and make sure you are getting the proper amounts.

2. Exercise. Okay, here’s how this part works…if your fitness level was extremely high before your pregnancy, you may need to bring it down a level. Remember, your baby’s heart rate will increase with your own. If your fitness level was low before your pregnancy, you’ll need to bump it up a notch. Activity is so important while you are pregnant. And yes, you absolutely can and should resistance-train to keep muscles toned and tight; just be careful with heavy weights over your uterus–like squats and/or power cleans–and stick to what you’re used to.

Blood circulation during activity means more oxygen and new nutrients to your baby. It also keeps you less likely to develop varicose veins and hemorrhoids.

To sum up, keep a finger on your heart rate, but be sure to get some type of cardiovascular activity in at least four times per week.

3. Vaginal birth and breast feeding. If you are serious about getting your pre-pregnancy body back and FAST, these two things make it 1,000 times easier! The vaginal birth is not possible for everyone. There are those unforeseen emergencies, but be informed about your decisions. C-sections in the U.S. are rising fast, and many of them are preventable. It is very hard to get that little baby pouch flat again after this highly invasive surgery. Once all of your abdominal and uterine muscles have been sliced through, you really have to work at getting things back to normal.

As for breast feeding, once again your body is very smart. If you use your parts how they are supposed to be used, you and your baby get rewarded.

First, the hormone oxytocin is released when your baby starts to feed. This hormone helps tighten your uterus and bring it to a normal size. I can usually tell by just looking at a mom if they breastfed or not (that little baby pouch is still there). If it’s too late for you, don’t worry, you’ll just need to work harder at tightening up the abdominal muscles in front of your uterus in order to hold it in place.

Second, breastfeeding literally sucks the calories right out of you. As long as you are exercising and maintaining your healthy diet, your baby will get nice and chubby (don’t worry, it won’t stay long), and you will drop the weight like a bad habit and FAST!

The most important thing to remember is not to lose control during your pregnancy. Stay healthy, fit and active, and you and your baby will both reap the benefits! Congratulations, and good luck!