Second trimester
5-minute read
The second trimester of pregnancy is a time when many women will feel energised and well. You will become visibly pregnant, but you won’t be so heavy that getting around is difficult. This is also a time of rapid growth and development for your baby, and you may find yourself busy with health checks and planning for the birth.
What is the second trimester?
Trimesters are a helpful way to think about pregnancy because the changes that happen to you and your baby fall into 3 broad categories of early, middle and late pregnancy, as reflected in the first, second and third trimesters.
The second trimester represents the middle part of your pregnancy, from weeks 13 to 26. For many women, one of the best things about this trimester is that nausea might begin to settle.
What happens to your body?
Your body will undergo some major changes during the second trimester. Your uterus will grow, and you may feel some discomfort or aches as uterine ligaments stretch. You will start to feel your skin stretch around your belly and your breasts, which may cause mild itching. Some women get stretch marks in these areas, which tend to fade over time.
Although your baby weighs less than a kilo, your blood volume will increase to meet the demands of all the growth happening inside you, which will mean you will gain some additional weight.
Your emotions
Pregnancy can be a wonderful and exciting time, but it’s also important to expect to feel some occasional days of heightened anxiety or low mood.
Sometimes one or both parents experience difficult emotions during pregnancy, such as being worried about the birth or about coping as a parent.
Feelings of anxiety are not uncommon, and some women will experience symptoms of a condition called anxiety disorder. Antenatal depression is a mood disorder that includes intense emotional changes beyond those you might expect during pregnancy.
If you are worried about feelings of anxiety, low mood or depression, you could:
- see your doctor, obstetrician, child health nurse or midwife
- phone Pregnancy, Birth and Baby on 1800 882 436
- call PANDA - Perinatal Anxiety & Depression Australia on 1300 726 306
What happens to the baby?
During the second trimester, your baby will grow from being around 7.5cm, and weighing 30 grams in week 13, to around 23cm and 820 grams at week 26.
Your baby will be able to move freely within the amniotic sac in your uterus. By about week 19 (or sooner if this isn’t your first pregnancy), you may feel this movement – as a faint tickling or fluttering. During these 3 months, your baby’s organs will continue to develop and the liver, pancreas and kidneys all start to function. This is also the time when babies might start to suck their thumb. By week 20 your baby can hear sounds, including the sound of your heartbeat, and they are learning to recognise your voice, although the ears are not yet fully formed.
What can you expect at your antenatal visits?
Regular antenatal visits are an important part of staying healthy and making sure your baby is healthy. How often you see your health professional will depend on your personal circumstances, but for many women, visits will be every 4 to 6 weeks.
At all visits during your second trimester, you will have your blood pressure checked, and your hands and feet will also be checked for swelling. You might be weighed, have blood taken for tests and have your urine checked.
Your doctor or midwife will check your abdomen to monitor your baby’s growth and will listen to your baby’s heartbeat. If you didn’t have an ultrasound in your first trimester, you may be offered one at around 18 to 20 weeks.
How to stay healthy
Eating well and staying active is as important as ever during pregnancy - it's good for your physical and emotional health, and good for your baby too. Light-to-moderate exercise in pregnancy is usually safe: consider walking, swimming, yoga and stationary cycling in your second trimester. High-impact exercise and activities where there is a risk of falling, getting hurt (especially around the stomach) or overheating are not recommended.
Your choice of food during your pregnancy is also important – but that doesn’t mean ‘eating for two’. What you eat during your pregnancy has been shown to affect how your baby grows as well as your baby’s health later in life.
Things to consider in the second trimester
Parental leave – discuss with your partner and then with your employer:
- How will you share the care of your baby with your partner (or other family members)?
- When do you plan to start your leave?
- When you intend to return to work?
- When is a good time to share your pregnancy news with your employer?
- Will your role at work change after your baby is born?
Antenatal classes:
- Ask your midwife or doctor about antenatal education available in your area.
- Consider going to classes together with your birthing partner – not only will you learn a lot about how to prepare for labour, you’ll meet people who will share their experience of becoming parents.

Your pregnancy journey
Follow your pregnancy week-by-week to find out how your baby is growing and what is happening to your body.
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Last reviewed: May 2021