Nutrition During Pregnancy by Trimester

Nutrition for a pregnant woman is the foundation of the future child’s health. During this period, the mother’s body works for two, so the diet should include a large variety of products, be balanced, and contain all necessary nutrients: proteins, healthy fats, trace elements, and a complex of vitamins.

Experts emphasize that balanced nutrition during pregnancy does not mean ‘eating for two.’ Experts highlight that during pregnancy, it’s important not to ‘eat for two,’ but rather slightly increase calorie intake in accordance with norms. For women with normal body weight during a singleton pregnancy, the additional energy requirement in the second trimester averages about 300–340 kcal per day, and in the third trimester—about 450 kcal per day, according to international and Russian guidelines (WHO and national standards of the Russian Federation).

Doctors pay special attention to trace elements like magnesium, zinc, and selenium, which are involved in the formation of the fetal nervous system, immunity, and protective mechanisms. They also help reduce the risk of cramps, increased fatigue, and pregnancy complications in the mother. On average, the daily requirement for magnesium in the first trimester is about 400–420 mg, and in the second and third trimesters — 450 mg; zinc — 11–12 mg per day throughout the entire pregnancy; selenium — approximately 60–70 mcg per day. Specific dosages, especially when taking supplements, should be selected by a doctor based on tests and diet.

Important! A lack of nutrients can lead to fetal development delays, and an excess of calories can result in excessive weight gain and complications during childbirth.

Let’s list the key principles:

• strive to ensure variety: include foods with plant fats and foods with animal proteins;
  
• avoid fried and spicy foods, opt for boiled, stewed, and baked products;
  
• include fresh vegetables and fruits, cereals, fermented dairy products;
  
• maintain a routine — eat small portions 5–6 times a day.

First Trimester: Key Nutrients for Fetal Development

The first trimester (1–13 weeks) is the most crucial period, where the child’s organs and systems are formed. It’s important to get the necessary vitamins and micronutrients now.

The diet should primarily consist of vegetables, fresh fruits, whole grains, dairy products, eggs, and dishes with fish and lean meats. These foods provide the essential proteins, calcium, and iron that support normal fetal organ development and strengthen the mother’s health.

Important! Folic acid (vitamin B9) is essential in the first months of pregnancy. It prevents neural tube defects in the baby. A doctor may prescribe additional vitamin intake.

To reduce the risk of toxicosis and nausea:

• eat quite often, but in small portions;
  
• exclude fried foods, high-fat foods, strong tea, and coffee;
  
• drink enough water and light beverages — such as warm kefir, unsweetened compotes, natural fruit juices.
  

In the case of anemia, a doctor may recommend foods rich in iron — beef, liver, buckwheat, spinach, apples.

Second Trimester: Increased Need for Protein and Calcium

In the second trimester (14–27 weeks), the fetus actively grows, muscles, bones, and the nervous system are formed. The diet of a pregnant woman should meet the increased need for protein and calcium.

At this stage, women often experience increased appetite, so it’s important to monitor the quantity and quality of food. The diet should include milk, cottage cheese, yogurt, lean meat, and fish. Calcium found in dairy products and broccoli aids in the formation of the child’s bones.

Products rich in magnesium and zinc are also necessary — legumes, nuts, cereals. They support the nervous system and reduce the risk of cramps.

To prevent constipation, it’s useful to include fiber — vegetables, cabbage, apples, whole-grain bread.

Important! Doctors recommend avoiding excessive sugar and sweets consumption. This will help maintain normal weight and prevent the development of gestational diabetes.

Third trimester: preparation for childbirth and prevention of complications

In the later stages (28–40 weeks), nutrition is aimed at maintaining the mother’s strength and the normal growth of the child. It is important to avoid overeating to prevent excessive fetal weight gain and complications during childbirth.

Let’s list what should be included in the diet:

• protein foods — meat dishes, fish, eggs, dairy products;
  
• iron and vitamin C — to prevent anemia;
  
• foods containing potassium (bananas, dried fruits, potatoes) — they reduce swelling;
  
• an adequate amount of fluids — at least 1.5 liters of water per day.
  

It’s better to limit salt, with a sufficient amount of fluids — on average from 1.5 to 2–2.5 liters per day, considering all drinks and liquid foods, of which usually no less than 1–1.5 liters should be plain water. The exact amount is selected individually: it depends on body weight, activity, time of year, and doctor’s recommendations, especially in case of a tendency to swelling or preeclampsia.​

By the end of pregnancy, the stomach is compressed by the enlarged uterus, so eat more often but in smaller portions, especially in the second half of the day.

Healthy foods and drinks for pregnant women

The diet of an expectant mother should not only be nutritious but also varied. The diet includes:

• vegetables and fruits — sources of vitamins, fiber, and antioxidants;
  
• dairy products, including those with natural starters — cottage cheese, kefir, yogurt;
  
• porridges and grains — buckwheat, oats, rice, millet;
  
• lean meats, baked fish dishes — sources of protein and omega-3 fatty acids;
  
• oils — olive, sunflower, flaxseed;
  
• nuts and berries — a source of healthy fats, antioxidants, and vitamins; nuts contain omega‑3 fatty acids and vitamin E, which are involved in the development of the fetal nervous system and brain and protect cells from oxidative stress.
  

It’s better to drink pure water, compotes, fruit drinks, juices without added sugar, and green and black tea in limited quantities: up to 1–2 cups of a lightly brewed drink per day, so that the total caffeine intake does not exceed approximately 200 mg per day, taking all sources into account (tea, coffee, chocolate, carbonated drinks).

When selecting products in the store, pay attention to the composition and safety for pregnant women. Dairy products should be pasteurized, with a not expired shelf life, without a lot of sugar, flavorings, and vegetable fats; for yogurts and kefir, a short shelf life and simple composition—milk and starter—is important. It is better to choose fish with low mercury content (hake, pollock, cod, herring, flounder, sardines, salmon), avoiding large predatory varieties like shark, swordfish, and large tuna, which accumulate more heavy metals. If there are doubts about the freshness, origin, or storage conditions of the product, it is better to refuse it.

What not to eat during pregnancy

Some foods can harm the health of the mother and child.

Should exclude:

• raw eggs, unpasteurized milk, raw fish;
  
• fatty, smoked, spicy dishes;
  
• caffeine and strong tea in large quantities;
  
• sweet carbonated drinks;
  
• alcohol — completely and at any stage.
  

Important! Even a small amount of alcohol can affect the development of the baby’s brain and nervous system.

Dietary regimen and eating rules

During pregnancy, it is especially important to adhere to a pregnancy nutrition regimen. The body of the future mother absorbs food better when it is consumed regularly and in small amounts.

Doctors’ recommendations:

• eat 5–6 times a day in small portions;
  
• start the morning with a light breakfast — porridge or yogurt;
  
• avoid long intervals between meals;
  
• do not lie down immediately after eating — this reduces the risk of heartburn;
  
• the last meal — 2–3 hours before bedtime.
  

If you experience severe morning sickness, try eating a small portion of crackers or an apple without getting out of bed. This helps reduce the symptoms of nausea.

Dietary Supplements During Pregnancy

Dietary supplements during pregnancy should only be taken as prescribed by a doctor. Despite their natural origin, the wrong choice of supplement can harm the health of the mother and child.

Most commonly prescribed supplements:

• Folic acid (Vitamin B9) — essential in the first trimester, reduces the risk of neural tube defects.
  
• Iron — for anemia and low hemoglobin levels.
  
• Iodine — for proper thyroid function and brain development in the child.
  
• Calcium and Vitamin D — strengthen bones and teeth and reduce the risk of cramps.
  
• Omega-3 fatty acids — promote the development of the brain and retina of the fetus.
  

Sometimes doctors prescribe special prenatal complexes that contain optimal doses of vitamins and trace elements for fetal development, tailored to the stages of pregnancy.

It is worth mentioning probiotics separately — live beneficial microorganisms that support a healthy gut and vaginal microbiome in pregnant women. According to clinical reviews, their intake during pregnancy and breastfeeding, in general, is considered safe and is not associated with an increased risk of miscarriage, developmental defects, or other serious adverse outcomes for the mother and child. Some studies indicate that certain probiotic strains may reduce the incidence of bacterial vaginosis, improve glucose metabolism, decrease the risk of gestational diabetes, and adverse immune reactions in the child. However, the selection of a specific medication and the duration of the course should only be conducted by a doctor, taking into account the gastrointestinal condition, past diseases, and already prescribed medications or vitamin complexes.

Supplements should not be chosen independently. Not all supplements are safe — some contain herbs and extracts that can increase uterine tone or cause allergies.

Recommendations for intake:

• take supplements only after consulting with a doctor or gynecologist;
  
• do not exceed the dosage indicated in the instructions;
  
• combine supplements with a full diet, and do not use them to replace nutrition in the first/second/third trimester;
  
• avoid taking several complexes at the same time — this can lead to an excess of vitamins (e.g., A and D).
  

Even the highest quality supplements do not replace a complete diet. Essential nutrients must come from food, and supplements should only complement the diet.

Conclusion and Useful Recommendations

Healthy eating during pregnancy is not a diet, but a system for maintaining health. In each trimester, the diet changes according to the needs of the body.

Key Rules:

• consume only fresh and high-quality foods;
  
• maintain a balanced intake of proteins, fats, and carbohydrates;
  
• drink enough fluids;
  
• consult with a doctor if there are any changes in your well-being.
  

A balanced diet promotes normal fetal development, prevents complications, and helps a woman recover faster after childbirth.

Pregnancy is a special period when nutrition becomes a part of medical prevention. Conscious food choices, moderation, and attention to the body’s signals are the keys to the health of mother and baby.

Frequently Asked Questions

1. Should a pregnant woman take additional vitamins?
Yes, but only as prescribed by a doctor. The majority of pregnancy vitamins should be obtained from food, although folic acid, vitamin D, and iron are often prescribed additionally, especially in the early stages of pregnancy.

2. Can you drink coffee during pregnancy?
Moderate consumption (up to 200 mg of caffeine per day) is permissible, but it’s better to replace coffee with chicory or green tea. Caffeine may increase blood pressure and cause an accelerated heartbeat in a pregnant woman.

3. What foods are best to eat with morning sickness?
Dry crackers, bananas, oatmeal, apples, and light vegetable soups are suitable. Avoid fatty and fried foods, strong smells, and spicy seasonings.

4. What meat and fish should you choose?
Dishes with a low-fat content, such as baked rabbit or chicken breast, are allowed. Fish with omega-3 (hake, cod, mackerel) is beneficial. All food should be thoroughly cooked—baked, boiled, or stewed.

5. Should you limit the amount of salt and sugar?
Yes. Excess salt causes swelling, and sugar increases the risk of gestational diabetes. Doctors recommend no more than 5g of salt and a minimal amount of sweets per day.6. How to eat if weight is increasing too quickly?
Reduce simple carbohydrates (sweets, white bread, pasta), it’s recommended to increase the intake of vegetables and protein-rich foods, as well as adhere to regular meal times and drink more water.