If your pregnancy test is positive, congratulations! You’re about to embark on a wonderful journey.

Your head is probably filled with questions like "how will my body change?" and "how quickly does the baby develop?". Although every woman’s experience is different, here's what you can expect during the three stages, or trimesters, of pregnancy.

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1st trimester  weeks 1 to 12

Pregnancy is calculated from the first day of your last period because it’s difficult to pinpoint the exact date you conceived. As conception typically takes place half way through the menstrual cycle, you’re not actually pregnant for the first 2 weeks, but they are still counted as the first 2 weeks of your pregnancy.

As soon as the egg is fertilised at around week 3, pregnancy hormones will start to shake things up a bit. As a result, you may experience some of the following symptoms.

Up to 80%4 of women may experience morning sickness with symptoms that include nausea and vomiting in the
1st trimester
  • Morning sickness: Up to 80%4 of women may experience morning sickness with symptoms such as nausea and vomiting in the 1st trimester, due to increased pregnancy hormones. It’s a common misconception that morning sickness only occurs in the morning. It can in fact strike at any time of the day or night. 1 in 5 women may experience morning sickness in the 2nd trimester and occasionally it can continue throughout their entire pregnancy.

    If you do experience morning sickness, stay away from foods that make you feel nauseous, eat little and often, avoid greasy and spicy foods and drink plenty of water. Our pregnancy nutrition page has more tips to help manage the symptoms of morning sickness. There are also supplements available to help you manage the symptoms such as Elevit Morning Sickness Relief. If your symptoms are severe or worrying, contact your doctor.
  • Breast changes: Your breasts will start to get bigger and they may be sore. Your nipples will become larger, darker and more prominent.
  • Tiredness: High progesterone levels, not to mention your body working overtime to grow a baby, can leave you feeling exhausted. Put your feet up as much as possible and eat as well as you can - tricky if you have morning sickness!
  • Increased emotions: It's normal to feel more emotional than usual, due to high hormone levels. Ask your partner and friends to be understanding and tolerant.
  • Food cravings and dislikes: You may find you can't bear, or crave, a particular food. This isn't usually a problem unless you've developed a taste for odd things. If you’re concerned, check in with your healthcare professional.
  • Increased need to urinate: As your body fluids increase and your uterus presses on your bladder, you'll want to go to the toilet more often. Go when you feel the need to help minimise unnecessary pressure on your bladder.
  • Feeling lightheaded: You may occasionally feel a bit dizzy. This can be due to hormonal changes. Try not to stand for too long and get up slowly from sitting or lying down. If the dizziness is severe see your doctor immediately.
  • Heartburn and constipation: Your digestive system will slow down to give your food more time to be absorbed. This can lead to heartburn and constipation.

    To help ease heartburn, try to eat small, regular meals and avoid fried or spicy meals and fizzy drinks. You may also like to take an antacid supplement that can be used during pregnancy, such as Rennie. Read our pregnancy nutrition page for more suggestions.

    To help ease constipation, eat plenty of high-fibre food, keep active and drink lots of water. If you are considering taking laxatives check with your doctor first. Download our free information sheet “Some facts about constipation in pregnancy”.
Foetus image trimester 1
Your 1st trimester milestones
  • Around 7 days after fertilisation, the embryo will implant into the lining of your uterus. The placenta, umbilical chord and amniotic sac will begin to form to nourish and protect the embryo.
  • By the end of the first 12 weeks, the uterus can be felt through your stomach and your belly will be beginning to swell.
Baby's 1st trimester progress

By the end of the 1st trimester:

  • All of the major organs have formed and blood is pumping.
  • The sex organs have started to develop.
  • The arms and legs have fingers and toes, and fingernails have appeared.
  • Facial features have formed.
  • Your baby will be about 6 cm long from head to bottom, and already recognisable. It’ll be moving around in the amniotic sac, but you won't be able to feel it yet.

2nd trimester  weeks 13 to 26

Most women enjoy the 2nd trimester more than the first as morning sickness, breast tenderness and tiredness begin to ease. Be prepared for a few new symptoms to appear.

  • Aches and pains: You may feel a few aches and pains along the sides of your body and under your belly as your body stretches. The extra weight may give you backache and you may get leg cramps. Ask your doctor about simple exercises that might help.
  • Stuffy nose: An increase in hormones can give you a stuffy nose or cause nosebleeds.
  • Soft gums: Your gums are likely to bleed more easily, so take pay attention to your oral hygiene routine and don't brush too hard.
The skin on your stomach may itch as it stretches over your growing baby bump. Try using a moisturiser daily to help avoid stretch marks!
  • Itchy skin: The skin on your stomach may itch as it stretches over your growing baby bump. Try using a moisturiser daily to help avoid stretch marks.
  • Varicose veins and haemorrhoids (piles):  You’ll be more susceptible to varicose veins and haemorrhoids during pregnancy. Avoid standing or sitting for too long and crossing your legs when you’re sitting down. You can get medication for haemorrhoids from your doctor.
  • Vaginal discharge: It’s normal to have a thin, white discharge, called leucorrhea, at this time. It helps keep your vagina healthy. If you see any other type or colour of discharge, get it checked out by your doctor.
  • Skin discolouration: Pregnancy hormones can cause dark patches on your face and stomach. The condition can be aggravated by the sun, so wear plenty of sunscreen when you’re outside. Slip, slop, slap!
  • Shortness of breath: As your lungs process more oxygen to carry to your baby, you may feel short of breath, or breathe slightly faster.
  • Increased appetite: Growing a baby may make you feel constantly hungry, but you don’t need to ‘eat for 2’. If you do need a snack, choose a healthy option like fruit or yoghurt. 
Foetus image trimester 2
Your 2nd trimester milestones
  • You may start to feel your baby move for the first time between 18 and 20 weeks. This phenomenon is called 'quickening' and feels at first like a fluttering in your belly.
  • Your pregnancy bump will be showing as baby continues to grow.
Baby's 2nd trimester progress

By the end of the 2nd trimester:

  • Your baby’s moving around and responds to touch and sound.
  • Eyelids are beginning to open, and eyebrows and eyelashes are visible.
  • The skin is covered with a fine, down-like hair, and a creamy white substance called vernix. 
  • Reflexes like swallowing and sucking are developing.
  • Hair has started to grow on the head.
  • Fingerprints are formed.
  • Your baby will be about 23 cm long from head to bottom.

3rd trimester  weeks 27 to birth

Almost there! You may feel more uncomfortable in these final weeks of pregnancy as your baby continues to gain weight and move around in a confined space. Try to rest as much as possible. You can also add a few more symptoms to the ones in the 2nd trimester, these include:

  • Swelling hands, feet and face: Excess fluids can cause your hands and feet to swell and your face to feel puffy. Try to put your feet up when you can.
  • Nipple leaks: Your nipples may start to leak colostrum, the liquid that feeds your baby until your breast milk kicks in. Wear breast pads to avoid any marks on your clothes.
You might feel some weak ‘practice’ contractions as your body prepares for birth
  • Braxton-Hicks contractions: You might feel some weak ‘practice’ contractions as your body prepares for birth. They’re called Braxton-Hicks contractions and they’ll come and go at irregular intervals. If they are strong and regular, call your doctor. You might be in labour.
Foetus image trimester 3
Your 3rd trimester milestones
  • By your due date, you will probably be carrying an extra 11 to 16 kilograms over your pre-pregnancy weight. This is mostly the weight of your baby, the placenta and amniotic fluid, and the increased body fat and fluids.
  • At 37 weeks, your pregnancy is considered full term.
Baby’s 3rd trimester progress

By the end of the 3rd trimester:

  • Baby’s probably pointing head-down into the pelvis, ready for birth.
  • Your baby’s body systems are developed and ready to function on the outside.
  • The soft, downy body hair has disappeared.
  • Your baby will be around 46–56 cm long from head to toe.

More tips on pregnancy

Are you feeling more prepared for the 3 stages of pregnancy? Now take a look at our pregnancy nutrition and lifestyle pages. They’re packed with useful information to help you keep in top shape and provide the support your growing baby needs.