If you're pregnant, you're very likely concerned about the amount of weight you're gaining, the effect it has on your body, even how difficult it will be to take off after your pregnancy. Your OB/GYN or midwife is your best source of advice about healthy weight gain during pregnancy, but there are general guidelines.

Depending on your weight at the start of your pregnancy, your doctor may tell you that a healthy weight gain for you is anywhere between 15 and 40 pounds. If you're underweight to start (a BMI of less than 18.5), 25 to 40 pounds is a reasonable weight gain during pregnancy. If you're overweight, he or she may suggest you stick closer to 15 to 25 pounds. Of that weight, 6 to 8 pounds of it is the baby. The rest is amniotic fluid, extra tissue and blood to nourish the baby (including the placenta), and the increased size of your breasts and placenta. You'll lose as much as 15 pounds of it WITH the birth (amniotic fluid, placenta and baby).

Any doctor will tell you that pregnancy is NOT the time to go on a diet. Your body AND your baby need the nutrients of an adequate, balanced diet to keep you both healthy. This doesn't mean that you should throw all your restraint to the winds and 'eat for two', though. Your body needs approximately an extra 300 calories a day to build a healthy baby. Those 300 calories should come from the same healthy variety of foods that your normal diet gives you. (You were eating a healthy, balanced diet, weren't you? If not, pregnancy is a great time to start.)

You can expect to gain weight along a fairly predictable pattern. In the first three months, you'll gain 2-4 pounds altogether. During the second trimester, you can expect to gain between 3-4 pounds a month (about a pound per week). During the last three months, you'll gain an additional 8-10 pounds. Your doctor or midwife will weigh you regularly, and may express concern over a deviation from this pattern. A sudden sharp weight gain, for instance, can indicate pre-eclampsia or gestational diabetes.

If your doctor advises you to try to limit your weight gain during your pregnancy, be sure to choose a healthy diet that provides all the necessary daily requirements for vitamins, minerals and other nutrients. Remember that a 'diet' during pregnancy isn't meant to help you LOSE weight, but rather to limit the amount of weight gained.

Regular exercise is also good for both you and your baby. You can maintain most of your daily activities, and if regular workouts were a part of your daily routine, then by all means keep them up. You'll feel better, and your body will be less likely to protest the extra weight with aches and pains. Do keep in mind that exercise during pregnancy shouldn't be overly strenuous, and that you should avoid activities with a risk of falling or injury. Also remember that your center of balance is different - it may feel awkward to do the things you usually do while you're carrying your little bundle of joy.

For specifics with regard to your own situation, speak with your doctor or midwife. If you're concerned about gaining weight, or feel that you're gaining too much, you can ask for a consultation with a nutritionist to help you design a healthy eating plan that will make sure the baby is well-nourished, and your concerns about your weight are met.