Pregnancy calendar

I TRIMESTER (0-16 weeks)

II TRIMESTER (16-28 weeks)

III TRIMESTER (28th week to term)

1st to 4th week

The first day of the last menstruation cycle is counted as the beginning of pregnancy. The duration of the pregnancy is usually 40 weeks or 280 days. A baby may be born starting from the 37th week of pregnancy up to 41 + 6 weeks and still be considered timely. An ovum developed in the ovary will be released to the oviduct during ovulation and as a result of the fertilization a zygote is created – the first cell of a child to be, storing the genetic information of their mother and father. A fertilized ovum attaches to the fluffy mucosa of the uterus, to be connected with the mother’s blood vessels. Internal cells will be divided into three layers, which will later develop into the body parts of the foetus. The primary germ layer of the ectoderm will develop into lungs, liver, digestive organs and the pancreas; the primary germ layer of the mesoderm forms the bones, muscles, kidneys, blood vessels and heart; the endoderm layer forms the skin, hair, eyes, tooth enamel and the nervous system.

What is happening to you?

  • You may be feeling more tired than usual and experience mood swings already in the beginning of the pregnancy.
  • The breasts may feel fuller, more sensitive and painful.
  • If a fertilized ovum attaches to the mucosa of the uterus, some bleeding may occur.


  • To alleviate the feeling of tiredness, try to rest as often as possible and do things that you enjoy.
  • If you haven’t taken folic acid while planning the pregnancy, start now. Folic acid supports the development of the child’s nervous system.

5th to 9th week

The spine, spinal cord and blood vessels develop. The beginnings of the liver and the pancreas emerge. Internal organs continue developing. The neural pipe connecting the brain to the spinal cord will close. On the sides of the future face, there are signs of future eyes. The first parts of the digestive system along with the abdominal and chest cavity and the vertebral column can be identified. The beginnings of limbs have developed. The placenta starts developing. The heart is beating and the blood circulation is independent. The oesophagus and the wind pipe are developing. The child starts moving. Toes and fingers form on what are to become legs and arms. The eyes are positioned wide apart, but the eyelids can be identified. Up until now the bone structure of the child was mostly cartilage, but now actual bone cells start replacing it. If the expected baby is a boy, the testicles will develop during this phase. The child is around 9-11 mm long on the 8th week.

What is happening to you?

  • Headaches and vomiting may occur, you urinate more often, may feel dizzy or nauseated and lose your appetite. Heightened sensitivity to smell, salivating and nausea may occur.
  • Blue blood vessels may show through the skin of breasts – the blood supply to the breasts is increased. The nipples may become darker.


  • Drink fruit juice and non-carbonated mineral water. Eat small amounts every two to three hours. Avoid coming into contact with irritating smells. Eat a few biscuits or toast in the mornings before getting out of bed. If you lose your appetite and vomit more than three times a day, contact your midwife or doctor.
  • On the 8th to 11th week, visit a midwife or a gynaecologist and register your pregnancy. The first analyses and tests are taken. Select the family school lectures needed at the start of pregnancy.

10th to 13th week

The bones and the joints of the baby grow stronger. The brain develops fast – every minute a million new brain cells are created. External sex organs start to develop. The eyelids are closed (they stay closed until the 25th to 27th week). Vital organs (liver, kidneys, intestines, brain and lungs) are fully developed and start functioning. By the end of the 12th week, the foetus is fully developed. When awake, they move actively; turn the head, clench fingers and toes and open and close the mouth, sometimes putting a finger in the mouth. By the 13th week the child is 9-10 cm long and weighs around 28 g.

What is happening to you?

  • During the 1st trimester, the normal increase in weight is around 1 kg. You may have lost weight due to nausea and/or vomiting. Nausea starts to reduce. When making sudden moves or when getting up from a chair you may feel weakness or dizziness.
  • Increased activity of the sweat glands. Small knots may appear near breast glands – these are the enlarged sweat glands.
  • Quick mood swings are caused by changes in hormonal balance and you may experience natural fears and doubts caused by pregnancy and becoming a mother.


  • Talk about your feelings with your midwife, doctor or pregnancy crisis advisor. Also talk to your husband and other members of the family so that they would better understand you and the processes going on with you. Try to experience only positive emotions, do activities that bring you joy.
  • In order to avoid swellings, watch your weight! Contact a midwife or doctor at the first signs of dehydration (the swelling of hands and feet). Excess body weight may also be a sign of an unbalanced and unhealthy diet.

NB! During a warm period, some swelling of hands and feet is normal. Drink water often. When resting, put your feet up.

14th to 17th week

The child starts reacting to loud sounds. Hair starts growing and the baby starts making breathing motions. The unique pattern has developed on the fingers. The nails have fully developed.

What is happening to you?

  • A pigmented line may appear on the centre of your stomach, which disappears after the baby is born. Sleeping is more uncomfortable due to the enlarged belly.
  • Nose bleeding and bleeding of the gums may occur. The first stretch marks may appear (pink lines on the stomach, thighs and hips).
  • Increased amount of the pregnancy hormone progesterone may slow the work of intestinal muscles. The enlarged uterus also affects the work of intestines and may hinder its normal activities.


  • Find a comfortable position for sleeping, put pillows under your feet and chest.
  • Drink more water, eat fruit and vegetables rich in fibres.
  • Move as much as possible: walk, swim and do exercises.
  • If constipation does not pass, consult a midwife or doctor.

18th to 22nd week

The baby can hear sounds transferred to the inner ear. The part of the brain that receives aural signals starts working. The sense of smell, taste, hearing, vision and touch are developing. The complicated nerve connections necessary for the development of memory and thinking are formed. The beginnings of permanent teeth appear.

What is happening to you?

  • You may feel the motions of the child. Movements start becoming palpable starting from the 20th week of the first pregnancy. Heart rate increases to around 80-90 beats per minute.
  • The level of pregnancy hormone oestrogen may cause pigment spots on the face, birthmarks and freckles may become darker. The natural cycle of losing hair stops (it will resume after childbirth).
  • You will lose your breath more often; due to less space in the abdominal cavity, your internals start pressing on the diaphragm, leaving less space for your lungs.
  • Your weight will increase but the rate should not be greater than 400 g per week.


  • Stay physically active. Special exercises designed for pregnant women will improve your mood and help prepare you for childbirth. Take part in the gymnastics group of the family school.

23rd to 27th week

The motions of the child become stronger. On the 26th week the baby will start opening their eyes. They are about 24 cm long and weigh a bit over 1 kg.

What is happening to you?

  • You have gotten used to the pregnancy and feel calmer. Your mood swings are less extreme.
  • You gain weight. Your stomach may tense unintentionally. If the contractions of the uterine muscle are painless, then everything is in order. If they are painful and frequent, consult a midwife or doctor.

28th to 31st week

The bone structure of the baby becomes stronger. The brain, muscles and lungs are improved. They start hearing sounds from the outside world.

What is happening to you?

  • The growing belly may become uncomfortable: it is difficult to walk, you tire much faster.
  • The lungs must use more oxygen with every breathing cycle.
  • Heartburn may occur due to the enlarged uterus.


  • Eat little at a time, some foods may invoke heartburn more easily. Take note of those which do, and avoid them.

32nd to 36th week

The nails reach the fingertips. The baby gains weight mostly in fat. The nervous system and the sexual organs keep on developing. The baby weighs around 2.2 kg and is about 45 cm long.

What is happening to you?

  • More colostrum may leak from your breasts.
  • If you have noticed rhythmic beats from your stomach, it might be that the baby has hiccups.
  • The bottom of the uterus now reaches your chest and may complicate breathing.


  • Sitting up as straight as possible and staying active will help alleviate discomforts. Posture can be improved through exercise.

36th to 40th week

The baby gains 23-30 g a day. You may notice that the baby moves itself less than before but that is due to it having less space. At the age of 40 weeks your child is ready to be born. Only 5% of babies are born on the expected date – you may give birth two weeks before or after your due date.

What is going on with you?

  • You should stop gaining weight, you may even lose some before birth.
  • The coming events will make you nervous. You are going to experience some degradation in your moods, caused by the vast amount of emotions experienced – fear of delivery, tiredness.


  • Consult a midwife or a doctor. Pregnancy affects you both physically and mentally and may bring forth smaller or greater challenges on different levels.
  • Gather as much knowledge as possible about pregnancy, delivery and the post-delivery period, in order to feel secure.

Knowledge gives strength and support

Our midwives and doctors are always by your side to make your pregnancy as pleasing and safe as possible.

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