First trimester: what happens in weeks 1–13 and what to do

The first trimester of pregnancy is the first 13 weeks, and for many women it is the hardest stretch to explain: you may feel exhausted and sick before anyone can see a change. Weeks are counted from the first day of your last period, so by the time a test turns positive you are often already about 4 weeks pregnant.

Most early symptoms are the body adjusting, and they ease for many women as the weeks go on. This guide covers what happens week by week, how to manage nausea and tiredness, your first checkup, food and daily life, the family side, a 7-day plan, and the few signs that need a hospital now.

What happens in the first trimester?

In these weeks, the baby's main organs, including the heart, brain and spine, begin to form. That is why these weeks are when folate in your food, and staying away from tobacco, alcohol and medicines your doctor hasn't given you, matter most. Your body is building the placenta and making more blood, and these changes, with the hormones behind them, are part of why you may feel so tired.

Some women have very few symptoms early on, and that on its own is not a warning sign. Every pregnancy is different, even for the same mother.

First trimester symptoms: how to ease nausea and tiredness

Nausea in early pregnancy is often called morning sickness, but it can come at any time of day. These small changes help many women get through it.

• Eat something small and dry before you get up, such as a handful of muri or a plain biscuit kept by the bed.
• Eat small meals every few hours instead of three big ones. An empty stomach often makes nausea worse.
• Sip water through the day, between meals rather than with them, and drink more in hot weather.
• Stay away from strong smells: let someone else do the frying and the tarka for a few weeks.
• Try what your body accepts: many women find cold or slightly sour foods, such as doi, fruit or a squeeze of lemon, easier.
• Rest is part of the plan, not a luxury: go to bed earlier and take a short nap when you can.

Your first prenatal checkup: when to go and what happens

1. 1Book as soon as you know you are pregnant. Many doctors like to see you before 12 weeks. Bangladesh's schedule is at least 4 checkups, from about 16 weeks; many doctors advise 8, starting at about 12 weeks. Your doctor sets your schedule.
2. 2Work out your due date and how many weeks pregnant you are with the due date calculator.
3. 3Bring your NID, the first day of your last period, a list of any medicines you take, papers from earlier pregnancies and your tetanus vaccine card if you have one.
4. 4Expect questions about your health and any earlier pregnancies, a blood pressure and weight check, blood and urine tests, and a scan if your doctor advises one.
5. 5Ask about the tablets pregnant women are given in Bangladesh, and about the tetanus vaccine.
6. 6Leave with your pregnancy (ANC) card, and keep it with you for every visit from now on.

The full schedule, what happens at each visit and the questions worth asking are in our guide to prenatal checkups.

Folic acid, iron and food safety in the first 3 months

Folate (in tablets it is called folic acid) and iron are two nutrients that matter from the earliest weeks: folate for the baby's early development, iron for the extra blood your body is making. Dal, chola, eggs, fish, meat and dark green shak such as lal shak, palong and pui shak all help. Pregnant women in Bangladesh are usually offered tablets too: ask at your checkup about the tablets pregnant women are given in Bangladesh, and take them the way your doctor says.

• Cook meat, fish and eggs well, with no runny yolks, and boil milk before drinking it.
• Drink safe water (boiled or filtered), and wash fruit and vegetables in it.
• Be careful with street food, fuchka water and cut fruit sold outside.
• No tobacco in any form, including cigarettes, bidi, jorda, sadapata, gul and pan with tobacco, and keep smokers out of the room.
• No alcohol, and no medicine, herbal remedy or kobiraji treatment your doctor hasn't agreed to.
• Go easy on strong tea and coffee, and ask your doctor how much is fine for you.

For a full day of Bangladeshi meals and the food myths you may hear, see what to eat during pregnancy.

First trimester dos and don'ts: rest, work and daily life

Most women can carry on with ordinary life in the first trimester, just more slowly. You don't need bed rest unless your doctor advises it for a reason.

• Keep moving gently: a daily walk and ordinary housework are fine for most women. Leave the heaviest lifting, such as full buckets or a gas cylinder, to someone else.
• Work: most women keep working. If nausea is worst in the morning, ask for a later start, a seat near the window or short breaks.
• If your job means heavy lifting, chemicals, pesticides or long hours standing, ask your doctor what to change.
• On a crowded bus or in traffic, carry water, a dry snack and a small bag in case you feel sick, and ask for the ladies' seat.
• Long, bumpy road journeys: ask your doctor first, and stop often to walk and drink water.

In a Bangladeshi home: telling the family, in-laws and old advice

• When to tell is your choice. Many couples wait until after the first checkup or about 12 weeks; telling one or two close people early can bring real help with nausea and cooking.
• "Eat less so the baby stays small and the birth is easy." This old advice can harm both mother and baby. A pregnant woman needs a little more food, not less.
• Customs such as kajal against the evil eye (nazar), or not going out after dark, are harmless; keep the ones that comfort your family.
• In a joint family kitchen, ask for one simple change: you eat when you are hungry, not last after everyone else.
• If Ramadan falls in these early weeks, families decide about fasting with their doctor and their own scholar. Raise it at your first checkup, well before the month starts.
• The husband can take over the jobs that make her sick, come to the checkups and learn the warning signs; see how to support your pregnant wife.

A 7-day plan for the first trimester

These weeks feel easier with a few things settled. Pick one step a day, and note how you feel each evening: sickness, tiredness and what helped.

1. 1Day 1: Work out your due date and your week, and write them down.
2. 2Day 2: Book your first checkup, and choose where you will go for the rest.
3. 3Day 3: Put a dry snack by the bed and a water bottle in your bag. Try small meals every few hours.
4. 4Day 4: Clear out tobacco and smoke from your home, and talk to whoever smokes.
5. 5Day 5: Agree with your husband which jobs he takes over for the next few weeks.
6. 6Day 6: Read the warning signs together, and save 999 and your hospital's number in both phones.
7. 7Day 7: Look back at your notes. Which foods, times and rest helped most? Keep those, and take your notes to the checkup.

When to get help in the first trimester

At night, if no doctor can be reached, "today" means the hospital where babies are born. The complete list, including the later signs, is on our pregnancy warning signs page.

Nausea, tiredness and moods in early pregnancy are easier to judge over a week than on one bad morning. ParentMind helps you note what happens each day, see patterns and get guidance: how ParentMind works.