Everything you need to know about the second trimester: weeks 13 to 28

The second trimester is the middle three months of your pregnancy. This is a time when lots of women tell the world they’re pregnant and begin to feel like the pregnancy is more ‘real’.

The second trimester of your pregnancy is from week 13 to week 28 - roughly months four, five and six.

As well as feeling and looking more pregnant during these weeks, you may also have more energy than you did in the first trimester. This will come as a great relief if you have been struggling with sickness, tiredness or anxiety about getting through the first trimester.

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As you go through the second trimester, you’ll gradually see your 'bump' grow and later you'll start to feel your baby moving.

Choices and decisions in the second trimester of pregnancy

You'll be offered blood tests and your second ultrasound scan at around 20 weeks. This scan looks at how the baby is growing and whether there are any causes for concern.

You have the right to say no to any test or scan that's offered. It is always your choice and the team looking after you will respect your decision.

If you haven't already thought about it, it’s a good time to start thinking about where and how you would like to have your baby. From home birth to hospital birth, you may have to make a decision. If this all seems a little scary, don't worry. Your midwife will be there to support you and tell you what your choices are. You'll go from beginner to expert in just a few weeks!

You may want to consider whether to ask if you’re having a boy or a girl when you have your scans. This is a very personal decision – some parents are excited to find out and others prefer to be surprised at the birth. Keep in mind, though, that a scan doesn’t always show the sex of the baby and sometimes what you are told could turn out to be wrong!

If you are still smoking – even if it’s just the odd cigarette – check out your local stop smoking options. If you stop smoking before the 15th week of pregnancy, the health risks for your baby go down. Stopping smoking is one of the best things you can do for the health of your baby.

Experts agree that staying active in pregnancy is good for you and your baby. You can prepare your body for the challenges of labour and being a mum by keeping yourself healthy and active during your second trimester.

  1.  Lee KA, Zaffke ME (2006) ‘Longitudinal changes in fatigue and energy during pregnancy and the post partum period’, Journal of Obstetric, Gynecologic, and Neonatal Nursing, 28 (2): 183–91
  2. NHS Choices. Ultrasound scans. http://www.nhs.uk/conditions/pregnancy-and-baby/pages/ultrasound-anomaly-baby-scans-pregnant.aspx (Page last reviewed: 30/11/2017 Next review due: 30/11/2020)
  3. England LJ, Kendrick JS, Wilson HG, Merritt RK, Gargiullo PM, Zahniser SC (2001) Effects of smoking reduction during pregnancy on the birth weight of term infants’, American Journal of Epidemiology 154(8): 694–701:http://www.ncbi.nlm.nih.gov/pubmed/11590081 
  4.  ACOG (2010) Smoking cessation during pregnancy, Committee Opinion 471, Washington DC, American College of Obstetricians and Gynecologists:http://www.acog.org/Resources-And-Publications/Committee-Opinions/Committee-on-Health-Care-for-Underserved-Women/Smoking-Cessation-During-Pregnancy
Review dates
Reviewed: 28 June 2018
Next review: 28 June 2021

This content is currently being reviewed by our team. Updated information will be coming soon.