At your first prenatal appointment, your doctor will provide guidelines as to what you should eat or avoid during pregnancy, as well as how much weight you should gain based on your pre-pregnancy weight. However, in most cases, this appointment typically isn’t until you are already eight or nine weeks pregnant. 

In the meantime, it’s not uncommon for women to turn to the internet or seek advice from family and friends. The result is an overwhelming amount of information, some of which can be false or contradicting, making it difficult to understand what’s actually important when it comes to prenatal nutrition. 

What’s important

Debbie Petitpain is a Sodexo Wellness Dietician at the Medical University of South Carolina. Provided

“The most important thing to remember about prenatal nutrition is that the goal is to nourish your body and your developing baby,” says Debbie Petitpain, a local registered dietician. “Be sure to include all of the food groups and abstain from smoking and alcohol.” 

Some women use the notion that they are eating for two as license to overindulge and give in to every craving. But Petitpain says the truth is that the calorie needs for expectant mothers do not go up until about halfway through pregnancy.

“What many women don’t realize is that you actually need more calories for breastfeeding than pregnancy,” she says. 

Petitpain has been a registered dietician-nutritionist for 16 years and joined MUSC in 2004. In addition to her role as Sodexo Wellness Dietician at MUSC, she serves as a national spokesperson for the Academy of Nutrition and Dietetics.

In response to the plethora of guidelines and recommendations regarding prenatal nutrition, she says some are folklore, but some are rooted in truth. Many of the foods that women are told to avoid during pregnancy may still be OK to eat, but may need to be prepared in a different way to eliminate harmful bacteria. 

According to the U.S. Department of Health and Human Services, exposure to harmful bacteria can lead to foodborne illnesses, such as listeria or salmonella. Symptoms of these conditions can be worse during pregnancy and may lead to miscarriage or premature delivery. Women should always consult with their doctor if they are ever unsure or have questions about food safety.

Nutrients you need

When it comes to vital nutrients, Petitpain says the most important aspect of a prenatal diet is caloric intake. How many calories you should consume during pregnancy will vary for each individual based on factors such as your pre-pregnancy weight, weight during pregnancy and activity level.

“On average, women in the second trimester will need to consume around 240 extra calories per day. In the third trimester, women need roughly an additional 100 calories on top of their caloric intake during the previous trimester,” says Petitpain.

In terms of vitamins and minerals, folate (or folic acid) is critical to the development of your baby’s central nervous system. According to the American College of Gynecology (ACOG), the brain and spinal cord begin to form starting in the first few weeks of pregnancy, which is before many women will even know they’re pregnant. Because of this, folic acid is important not only during pregnancy but also for women who are actively trying to get pregnant.

The most convenient sources of folic acid are fortified cereals or your prenatal vitamin. 

Omega-3 fatty acids are also important during pregnancy as they support brain development and immune function. Unlike some vitamins and minerals, our bodies cannot produce them on their own, so the only way to get an adequate amount is through diet and supplementation.

The most beneficial omega-3s during pregnancy are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). According to research published in Obstetrics & Gynecology, the benefits of the omega-3s EPA and DHA include supporting the healthy development of the fetal brain, eye, and nervous system, healthy birth weight and gestational length, healthy immune system development, positive mood and well-being in mothers and attention and focus in infants and children.

Fish, vegetable oils such as canola or soybean, flaxseed, chia seeds and walnuts are some of the best ways to add more omega-3-rich foods into your diet. Although they are the leading recommended source for omega-3s, nearly all fish and shellfish contain traces of mercury. Pregnant women should refer to the Food and Drug Administration’s (FDA) list on what types of fish to eat and avoid. 

Other essential nutrients include calcium, iron, vitamin A, vitamin B12, vitamin D and protein. Keep in mind that getting enough of the right vitamins and nutrients can be difficult through diet alone. That’s why your prenatal vitamin is crucial during pregnancy, according to the American Academy of Pediatrics.

Your doctor might also recommend that you take other supplements including calcium and vitamin A during pregnancy. Certain diets can also increase the likelihood that you’ll need to take additional supplements during pregnancy. 

“Vegetarian and vegan diets are perfectly healthy at all stages of life including during pregnancy, while breastfeeding and even as your child starts solids,” says Petitpain. “But you may need to supplement omega-3s, vitamin B12 and vitamin D.” 

Regardless of your dietary preferences, pregnant women also need to make sure they’re drinking plenty of water. Water helps carry nutrients through your body to your baby and helps maintain healthy levels of amniotic fluid.

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Avoid eating too much

When trying to ensure you’re consuming enough calories and getting the right nutrients, you also want to avoid excessive eating which can lead to excess weight gain for both you and your baby.  This can increase your risk of gestational diabetes and the need for a Caesarean section due to the baby’s large size. 

“Pregnancy is about appropriate weight gain,” says Petitpain. “And that ultimately comes down to portion control.” 

Sometimes small meals throughout the day versus eating fewer large meals can help curb nausea, but otherwise, she says it’s important to watch out for grazing or continuous snacking.

In addition to the benefits mentioned early, drinking enough water can also help you avoid eating too much during pregnancy because thirst can mask itself as hunger. If you’re having trouble telling the difference, keep a bottle of water on your desk or in your purse. If you think you might be hungry, drink some water and wait 15 minutes to see if you feel satisfied.

While gaining too much weight is a concern for many expectant mothers, many women also struggle with the opposite problem. In some cases, women may even lose weight during pregnancy, especially those with conditions like hyperemesis gravidarum (extreme nausea and vomiting).

Like the recommended calorie intake, the appropriate weight gain for you depends on a variety of factors including your pre-pregnancy weight and body mass index (BMI). The general guidelines from the Centers for Disease Control and Prevention (CDC) for pregnancy weight gain are as follows: 

Women who are underweight with a BMI less than 18.5 should gain 28 to 40 pounds. Those that are normal weight (BMI 18.5 to 24.9) are recommended to gain 25 to 35 pounds. Women who are considered overweight (BMI 25 to 29.9) should gain 15 to 25 pounds and those that are obese (BMI 30 or more) between 11 to 20 pounds.

“Keep in mind, there’s only so much you can do in terms of your weight during pregnancy,” says Petitpain. “Pregnancy is your first parenting lesson in choosing your battles because the reality is that your baby is in control. Trust your body and that it will do what it needs to.” 

Petitpain says instead of focusing on how much weight you are gaining (or not gaining) during pregnancy, channel that energy into making sure you are eating a well-balanced diet and staying active. And if you need to, throw out your scale. Your doctor will measure and monitor the growth and development of your baby throughout your pregnancy, which at the end of the day is what is most important. LCP