How to Increase Fetal Weight During Pregnancy 2025: Foods & Diet Tips

Many women worry about low fetal birth weight. Often, low birth weight comes as a consequence of premature birth, but other developmental delays may also put your child at risk of being born too small. 

Low birth weight is often found in smokers, those who use alcohol or illicit drugs, those moms who receive inadequate prenatal care, and those who experience pregnancy complications.

Can you eat certain foods to make the baby gain weight or grow faster in the womb? Can weight gain during pregnancy aid your unborn child in fetal weight gain? Read on to learn all about healthy weight gain as your new baby develops in utero.

Between ethnicities, this number may vary even more.

Your baby’s weight in the womb is only part of the equation, however—the average woman gains approximately 25 pounds^[2] in gestational weight gain. Your baby, the placenta, and the amniotic fluid supporting her as the pregnancy continues will usually only account for around 35% of this weight gain.

Conception, gestation, and birth are all dependent on a healthy body. A short gestation period, or gestational age,  is one common factor leading to premature birth and low fetal weight^[3]. Other factors that may impact the fetal weight and your baby’s well-being include

• Maternal age
• Intrauterine growth restriction
• Stress during pregnancy
• Malnutrition before and during pregnancy
• Socioeconomic status
• Illness
• Tobacco use
• Overexercising, especially after 31 weeks of pregnant
• Previous premature birth or underweight birth
• Presence of hypertension

Avoiding all of these issues while pregnant is, of course, one way to influence baby weight gains and to encourage your body to produce maternal tissues in abundance. Doing so may also support your baby’s development, and even assist in preventing birth defects in some extreme cases.

Foods to Help Baby Gain Weight During Pregnancy

Preventative measures against low birth weight babies are contested^[4], but there are some ways to help you increase fetal weight. These are the best foods to make your baby gain weight in the womb.

Can your diet impact your baby’s health? It can, which is why pregnant women should ensure that they’re including all the most important^[5] essential nutrients vital to their unborn baby’s health, throughout their pregnancy and especially in the third trimester when the baby’s weight gain is most rapid.

Calcium

Calcium intake is paramount when pregnant—your body needs sufficient calcium to facilitate your unborn child’s bone mineralization. This extremely taxing process requires this nutrient to be supplied adequately or it will be taken from the mother’s bones and teeth. Low-fat dairy is one of the best ways to get your fill.

Folate

Folate, a water-soluble B vitamin, can be taken in the form of folic acid, its synthetic counterpart. It’s much better to receive this nutrient naturally when pregnant, however—dark leafy greens, fortified cereals, and citrus daily should have you covered. 

If you aren’t getting enough folate, your child may be at risk for premature delivery and serious neural tube defects as your pregnancy progresses. The best time to start boosting folic acid is before you get pregnant and in the first few weeks after conception.

Vitamin A

Vitamin A can help support maternal growth and tissue maintenance and may even prevent you from becoming anemic during pregnancy. Kale, sweet potatoes, and carrots provide carotenoids like beta-carotene, which are then metabolized into vitamin A in your liver after metabolism.

Vitamin B

All B vitamins: 

• vitamin B1 (thiamine)
• vitamin B2 (riboflavin)
• vitamin B3 (niacin)
• vitamin B6 (pyridoxine)
• vitamin B12 (cyanocobalamin)

These B vitamins will usually be included in the average dose of prenatal vitamin supplements most pregnant women are prescribed. Deficiencies in any of the above may take a negative toll on your child’s brain development. 

Lean meats, fish like king mackerel, fortified cereal, dairy, beans, and leafy greens can all help pregnant women maintain a balanced diet rich in these important compounds.

Vitamin C

Vitamin C, found in citrus fruits, tropical fruits, tomatoes, and other fruits and vegetables, works alongside vitamin E in the body, combatting oxidation and free radical activity and encouraging cellular turnover. Your growing child needs a ton, which is why many experts recommend around 60–85 milligrams (mg) of vitamin C a day for both pregnant and breastfeeding women.

Iodine

Iodine is imperative to proper thyroid health. You’ll find it in iodized salt and pretty much anything from the ocean—seaweed, kelp, and seafood. The thyroid, which is dependent on iodine for proper functioning, is responsible for orchestrating your pregnancy and your baby’s development, resulting in a healthy baby that isn’t as likely to be underweight.

Iron

More iron than usual is necessary for a healthy baby, as your body is producing more blood for your unborn child. Animal-derived iron is more bioavailable than non-heme iron, but both should be included for a healthy pregnancy diet and for a newborn of normal weight. Heme iron is obtained from animal sources while non-heme iron is obtained from vegetables and fortified foods.

Vitamin D

Aside from these edible vitamins, vitamin D is also extremely important. Your body produces vitamin D in response to exposure to UV-B rays from the sun. As many as 40 to 98% of pregnant women are vitamin D deficient—if the sun is out, do what you can to soak it in, lest you run the risk of a child with rickets or even more serious conditions like preeclampsia.

Mostly, we encourage you to limit sweets, salty foods, processed foods, high-calorie snacks like fried potato chips, and sugary drinks. Substitute your usual soda with fruit juices, and never eat raw eggs or fish.

Your diet should consist mostly of lean meat, green leafy vegetables, complex carbohydrates like whole grains, healthy fats, and as many fruits and vegetables as you can. 

The best way to stimulate fetal weight gain is, of course, to make sure that you’re eating around 2,200 to 2,400 calories per day. The extra calories will carry over to your baby’s weight, both in the form of pure fetal weight gain and in the delicate processes that a nutritionally-complex diet makes possible.

Safety Precautions

Most will agree that a healthy pregnancy actually begins before conception^[4]. Tons of outlying factors may impact your baby’s brain, cell, and muscle development, such as financial limitations and a lack of access to maternal care.

If you’re asking “How much weight can I lose while pregnant?”, you may want to reconsider starting a family any time in the immediate future. Those afraid of gaining weight are not advised to become pregnant. 

If a new mother doesn’t gain enough weight, her unborn baby may also suffer, as well. No doctor will recommend that a pregnant woman lose weight, which also puts her unborn baby at risk.

The Bottom Line

Mothers-to-be should never be worrying about how to not gain weight during pregnancy unless suffering from a medical condition such as gestational diabetes or maternal obesity where weight gain may be restricted. 

Follow your physician’s expert advice for ideal baby weight gain that keeps your baby’s growth on track throughout your entire pregnancy.

It’s unlikely that you’ll be unable to gain enough weight to support your child, especially through the third trimester. Include a diverse range of healthy foods in your diet, and limit sweet, nutritionally void foods whenever possible. 

All the weight you gain during pregnancy will be to the benefit of your future child—follow your instincts, listen to your doctor, and enjoy one of the most exciting times in any person’s life.

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