Your Diet And Nutrition In The First Trimester

Written by Dr. Pramod Mane on Tue, 01 August 2023

Key Highlights

  • The first trimester is the period of the first 12 weeks of pregnancy.
  • Fetal growth during the first trimester is rapid and gradual.
  • Eating nutritious food and avoiding unhealthy substances can benefit the growth of the embryo.
  • Counting on supplements can help in dodging nutritional deficiencies if any.
  • Being mindful of the dos and don'ts during the first trimester can pave the way for a safe and sound pregnancy.

Pregnancy is a crucial time in a woman's life. The first few weeks of pregnancy can be of utmost importance for the mother and her little one. Getting through the first trimester of pregnancy safely can indicate a reduced risk of early miscarriage. This is a great achievement for any couple looking forwards to becoming parents. So, now it's time for you to start looking into how you can achieve the same. Diet during the first trimester is very important. We're sure you must be wondering what to eat during the first trimester.

Motherhood-a journey

Pregnancy brings new emotions, feelings, and experiences into a woman's life. It is the beginning of a beautiful and lifelong journey called motherhood.

Once pregnant, the woman's body goes through numerous changes to accommodate a new life within her. Most women embrace these changes and believe in celebrating every step of pregnancy. However, being careful at every point is a must.

What is the first trimester?

The first trimester refers to the first 12 weeks of pregnancy starting from the first day of your last period. In this period, the fertilized egg or the zygote (formed from the fusion of the female ovum and the male sperm) divides and re-divides rapidly into a ball of cells that implants itself into the walls of the mother's uterus.

These layers of cells become an embryo, and develop bones, a heart, and a heartbeat! This development is crucial and rapid. We often hear doctors advising women in their first trimesters to be extra careful about their health and nutrition. This is because the growing baby has special needs. Does this mean eating more food? What are the developmental stages during this period? Read on to understand better.

Stages of growth during the 1st trimester

At the beginning of the first trimester, the zygote is a mere cell that is growing by multiplying continuously. If the zygote splits and multiples, it leads to multiple zygotes meaning twins or multiple pregnancies.

  • During the first and the second week, conception occurs. The usual duration of the conception is 2 weeks after your last period. To calculate one's due date, the healthcare provider will count 40 weeks ahead of your last period. This signifies that your period is also counted as a part of your pregnancy.
  • The fertilization in the fallopian tubes and the zygote formation occurs during the third week of pregnancy. The formed zygote travels down the fallopian tube towards the uterus for the next step of the process. The chances for any couple to conceive are about 15-25% during any time of the month.
    A zygote has 46 chromosomes, 23 from the biological mother and 23 from the biological father. These chromosomes will help in determining the baby's sex and gain its physical, mental, and emotional traits which will keep developing and changing further in their life.
  • The fourth week of the 1st trimester is when implantation takes place. The rapidly dividing mass of cells is now called the blastocyst. This blastocyst tries to implant itself in the walls of the uterus that is, in the endometrial lining. This process of the attachment of the blastocyst to the uterine lining is known as implantation. Implantation is an important step that can play a significant role in the development and childbirth of a baby.
  • The fifth week of the first trimester has a lot of changes going on. There are hormonal changes that set the stage of pregnancy into motion. The implanted blastocyst secretes high levels of the hormone Human chorionic gonadotropin (HCG). The ovaries detect the high levels of hormone HCG in the body and this is a signal for the ovaries to cease the release of eggs and up the secretion of hormones Estrogen and Progesterone. These increased hormones stop menses in the female body (the first sign of pregnancy) and fuel the early development of the placenta.

At 5 weeks, the embryo is now made up of 3 layers of cells:

  • The Ectoderm: This is the outermost layer of the embryonic cell. The ectoderm will give rise to the skin, eyes, inner ears, and central and peripheral nervous system of the growing embryo.
  • The Mesoderm: This is the middle layer of the embryonic cell. This layer will give rise to internal organ systems like the cardiovascular system, circulatory system, urinary system, reproductive system, and even bones and ligaments.
  • The Endoderm: This is the innermost layer of the embryonic cell. This layer is where the intestines and the gut system of the baby will form. It is also where the lungs and the respiratory system of the embryo will develop.
  • During the sixth week, the growth of the embryo is rapid. This is the week when the C-shaped development of the embryo starts. The Neural tube, which is developing since the 4th week finally closes. This leads to the development of the baby's brain, spinal cord, heart, and other organs. Various structures like eye sockets, ears, and small protrusions for arms start to form during this stage.
  • During the seventh week of the first trimester, the baby begins growing rapidly with its head and face developing and taking shape. The head grows rapidly whereas the face forms protrusions that will soon form the bridge of the nose and nostrils. Lower limbs that will soon become legs appear whereas the arm buds develop and turn into the shape of paddles.
  • The eighth week of the first trimester brings in visibly prominent changes. The face of the baby begins to take a more prominent shape with eyes, ears, nose, and upper lips being formed. The lower limbs beings to develop into paddles and the trunk of the neck begins to straighten. The fingers of the baby start developing. By the end of this week, the length of the embryo will be about ½ an inch in length from crown to rump.
  • In the ninth week of the first trimester, the baby's arms grow and elbows appear. The toes of the baby can be seen. Apart from this, the eyelids of the embryo develop. By the end of this week, the baby might be around 3/4th of an inch in length from crown to rump.
  • During the tenth week of the first trimester, the embryo can now bend its elbows! The digits of the legs and hands lose their webbings, grow longer, and can fold. During this stage, the umbilical cord is visible whereas the eyes and ears continue to mature.
  • In the eleventh week of the first trimester, the embryo is now officially called the fetus. The head of the fetus as compared to the rest of the body is pretty giant during this stage. Eyelids are fused, ears are set low, teeth start to grow, red blood cells begin to form, and the external genitalia- the clitoris or the penis begin to develop depending on the baby's sex.
  • The end of the twelfth week marks the end of the first trimester. By this stage, the fetus is around 2 ½ inches in length from crown to rump. At this stage, the baby has grown fingernails, developed intestines inside the abdomen, and has a well-defined face.

What to eat in the first trimester of pregnancy

For a healthy and safe first trimester, the nutrition and diet of the pregnant lady must be paid special attention to. If you're looking for a healthy pregnancy meal plan first trimester or the best foods to eat in the the first trimester, you're at the right place.

Here are some tips for a nutritionally sound 1st trimester:


1.Watching your food proportions

Pregnancy does not require overeating large amounts of food. The embryo derives nutrition from whatever food the mother eats. During the first trimester, the embryo does not require any additional calories for its growth.


The daily average calorie intake for women is around 2000 calories per day. Eating nutritionally adequate food that fulfills this requirement is a must during the first trimester.
Eating healthy fats, proteins, carbohydrates, vitamins, and minerals in adequate proportions will help the mother and the child go throughout this period without any issues.

The key is to focus on the quality and the proportion of the food consumed. Consuming too many calories can lead to unhealthy weight gain, gut issues, and even hormonal imbalance.

Eating the right amount of nutritious food is the golden step it takes to get through the first trimester safely.


2. Focusing on the nutritional value of food

Many times it happens that pregnant ladies eat the required amount of calories, however, they lack the nutrition that is required for the growth and development of their baby. The food they consume is just empty carbohydrates with no essential minerals and vitamins. This can lead to nutritional deficiencies and weak progeny.

Eating vitamin and mineral fortified foods can help you get the right nutrients in daily life. Eating fresh vegetables like spinach, beets, kale, and broccoli along with beans and lentils can help in obtaining iron and other essential nutrients.

Including eggs, lean meat, dairy or vegan sources of proteins like soy and soy products in your diet can help in achieving the daily protein requirements of the body.

Eating whole grains like oats, millets and cereals can help you get dietary fiber along with healthy carbohydrates.

Eating healthy fats like olive oil, ghee, avocadoes, nuts, and seeds can help in balancing your meals.

Focusing on eating fresh and healthy food that is high in nutrition is the best way to start your pregnancy in the first trimester.

The Best foods to eat in first trimester


1. Including fiber in every meal

Throughout the first trimester, many women experience severe hormonal changes. These changes can have an impact on their gut health and the rest of their health. Fluctuating levels of estrogen and progesterone in a pregnant woman's body cause digestive problems like constipation or diarrhea.

Including fiber in every meal in some or other form can help in bulking up the stools which can ease these problems. Eating salads with every meal, including fibrous snacks like nuts, chewing on seeds, choosing whole-grain foods, cereals, etc. are some ways of increasing the fiber content of your food.

Fiber can help in maintaining regular gut motion which can also help in alleviating problems like bloating, uneasiness, and stomach aches during pregnancy. Choosing high-fiber food options is a great way to ease your first trimester and establish good gut health.


2. Drinking plenty of water

Water is a revitalizing fluid that detoxifies and replenishes our bodies. Various problems like brain fog, headaches, migraines, inability to concentrate, etc. are common during pregnancy. Drinking plenty of water throughout the day can help in reducing these problems and bringing balance to your body.

Other gut issues like constipation, indigestion, and gut dysbiosis can be a result of drinking little water throughout the day. To avoid the discomfort of such ailments during the first trimester of pregnancy it is recommended to stay hydrated and drink plenty of water throughout the day.

Water also helps in balancing the hormones and calming the mind which is important considering that the hormones do go haywire during the first trimester of pregnancy.

It is advised to drink around 8-12 glasses of water a day to avoid dehydration during pregnancy. Placing your water bottles in front of your work area or somewhere visible can be helpful in drinking water at regular intervals.


3. Counting on supplements for nutrition

Nutritional deficiencies during pregnancy are a common occurrence. Low levels of essential vitamins, minerals, and trace elements can have a negative influence on the growth and development of the embryo.

The first step in avoiding these problems should be getting screened for any nutritional deficiencies. This can help you realize what elements your body lacks and how you need to pay more attention to attain the same.

From the inception of your pregnancy till the completion of it, 400 micrograms of folic acid are recommended every day. This is to reduce any problems related to the baby's early development.

A vitamin D supplement is also recommended. Precautions should be taken that the dose per day is not more than 100 micrograms.

Being updated with your health profile and being aware of pre-existing health conditions , if any, can help you understand what your body needs more. Vitamin C, iron, calcium, and B vitamins are some more essential supplements that you can ask your doctor about during pregnancy.

What foods to avoid during pregnancy!

There are some foods and habits that can pose a threat to the growing embryo. Avoiding these things is the sanest choice a new mother can make for her baby.

Here's a list of things you should avoid during your pregnancy:

1. Excessive beverages

Sipping on beverages like tea and coffee 1-2 times a day is usually considered normal. However, making it a habit can dehydrate your body. It affects the composition of your baby's amniotic fluid. Limiting your caffeine intake is a good choice to make during the first trimester.

2. Smoking kills

Smoking can pose a health hazard for not just the mother but also her growing baby. 1 in 5 babies with smoking mothers has low birth weight. Smoking can increase the chances of miscarriages and also cause cancer. Smoking cessation during pregnancy can give the baby a healthier life.

3. The hazardous drinks

Drinking during pregnancy also increases the chances of miscarriages, low birth weight of the baby, premature birth, and so on. These small shots of alcohol can cause big threats to your baby's life. Staying off alcohol or limiting its consumption is essential for the health of the baby.

4. Deadly combinations: Unprescribed Drugs/medications

Taking unprescribed drugs or medications can tamper with the natural rhythm of the body and even interfere with the absorption of nutrition for the baby. Some drugs can harm the growing embryo and even lead to miscarriages. Avoid taking any medications or drugs without consulting the doctor during the term of your pregnancy.

5. Eat to live, not live to eat

Overeating can lead to digestive problems , weight gain, uneasiness, nausea, and vomiting. This can affect the overall health of the mother and harm the baby.
Avoiding overeating while eating the right amount of food is the way to a healthy pregnancy and life.

6. Junk food or slow poison?

Eating unhealthy or stale foods is as good as consuming a slow poison. Junk food or snacky foods have no nutritional value and are full of empty calories that can do no good for the growing embryo. Biding goodbye to these during pregnancy is a wise choice for the mother as well as the baby.


The first trimester is all about embracing a new life and staying healthy to nourish the baby. Understanding the various stages of growth of an embryo enables us to understand the importance of nutrition in this process. So, watch out for diet during the first trimester and what to eat during the first trimester.

While choosing the best foods to eat in the first trimester, watch your food proportions, the nutritional value of the food, its fiber content, macro, and micro-nutrients, need for supplements, and more! Also, avoid bad habits like smoking, drinking, doing drugs, or being irresponsible with food and medications.

Pregnancy is a beautiful journey, all it needs is the right management through diet and healthy food, and a few lifestyle tweaks.  You can always rely on us for credible health information.


Dr. Pramod Mane

A Doctor of Medicine (MD) in Pharmacology., currently based in Mumbai, India, Dr Pramod Mane, comes with an experience of more than 20 years of working in Medical Affairs in the Pharmaceuticals & Nutraceutical Industry. Director of Medical Services at Mega Lifesciences since 2008, Dr Mane has been associated with several MNCS in the areas of Medical Affairs, Medical Services, Medico-marketing, Pharmacovigilance & Clinical trials in his illustrious career.

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Current Version

Aug, 01 2023

Written By

Dr. Pramod Mane