Tommy's PregnancyHub

C-section information for overweight women

If you have a high Body Mass Index (BMI), you’re more likely to need a caesarean section (c-section). Keeping active and eating healthily can help you recover from the surgery.

You may decide to have a planned c-section if your healthcare team think it is the safest option for you and your baby. This will depend on your wishes as well as your general health and whether you had any problems during pregnancy. 

If your BMI was 30 or more before pregnancy, you’re more likely to need an emergency c-section.  

Body Mass Index

One way of finding out whether you are a healthy weight is to measure your Body Mass Index (BMI). We have a BMI calculator that tells you what your BMI is, based on your height and weight.

Your BMI will increase during pregnancy so use your pre-pregnancy weight to measure your BMI. If your BMI before pregnancy was between 25 and 29.9, you are in the overweight range. If your BMI was 30 or more, you are in the obese range.  

Your midwife or doctor may use the words ‘overweight’ or ‘obese’ to describe your weight. Many women don’t like these descriptions but your healthcare team will only use them to make sure you get the right care. Nobody will judge you or your weight. 

What are the risks?

Having a high BMI does not always mean you will need a c-section, but you are more likely to have one.The higher your BMI, the more likely you are to need a c-section.  

If you have a BMI of over 30, you’re more likely to have problems during and after a c-section, such as:

  • your c-section wound getting infected – your doctor will give you antibiotics during your c-section to lower this risk 
  • problems caused by the anaesthetic if you have night-time breathing problems (sleep apnoea) – the team will monitor you closely for 12 hours after your c-section   
  • blood clots –  you will have daily injections of a blood-thinning drug for 1–6 weeks after your c-section to reduce this risk.    

You’re likely to see a consultant obstetrician at least once during your pregnancy. This is the most senior doctor who specialises in care during pregnancy, labour and after birth. They will work with you and the rest of your healthcare team to plan your antenatal care and the type of birth you would like

Find out how you can stay healthy during pregnancy and birth.

Diet and exercise

Your midwife, health visitor or GP can support you to keep active and follow a healthy diet. Find out what exercise you can do safely during pregnancy

Avoid strict diets when you’re pregnant or breastfeeding as it may harm your baby or affect your milk supply. Read more about breastfeeding after a c-section.

Keeping active after your c-section will help you recover physically and mentally. Going for gentle walks with your baby is a good way of keeping active while you’re recovering from your c-section. After your 6–8 week postnatal check, you could try going for brisk walks or swimming if you don’t have any pain or discomfort.  

Listen to your body and avoid pushing yourself too hard while you’re recovering from the surgery.

If your BMI is 30 or more, losing weight before your next pregnancy will improve your chance of having a vaginal birth after a previous c-section (VBAC)

  1. Denison FC et al. (2018) Care of Women with Obesity in Pregnancy. Green-top Guideline No. 72. Royal College of Obstetricians and Gynaecologists.  BJOG.
  2. Kalliala I et al (2017). Obesity and gynaecological and obstetric conditions: umbrella review of the literature. BMJ 2017; 359: j4511.
  3. NHS. BMI healthy weight calculator. www.nhs.uk/live-well/healthy-weight/bmi-calculator/ (Page last reviewed: 05/11/2018. Next review due: 05/11/2021)
  4. NHS. Obesity: overview. www.nhs.uk/conditions/obesity/ (Page last reviewed: 16/05/2019. Next review due: 16/05/2022)
  5. NHS. Obesity and pregnancy. www.nhs.uk/pregnancy/related-conditions/existing-health-conditions/overweight/ (Page last reviewed: 20/01/2020. Next review due: 20/01/2023)
  6. NICE (2021). Caesarean birth: NICE guideline 192. National Institute for Health and Care Excellence www.nice.org.uk/guidance/ng192  
  7. NICE (2010). Weight management before, during and after pregnancy. Public health guideline 27. National Institute for Health and Care Excellence. www.nice.org.uk/guidance/ph27
  8. RCOG (2015). Reducing the Risk of Venous Thromboembolism during Pregnancy and the Puerperium. Green-top Guideline No. 37a. Royal College of Obstetricians and Gynaecologists www.rcog.org.uk/globalassets/documents/guidelines/gtg-37a.pdf
Review dates
Last reviewed: 16 July 2021
Next review: 16 July 2024