Being overweight or obese does not always mean you will need a caesarean section (c-section), but you may be more likely to have one. The more overweight you are, the more likely you are to need a c-section.
Body Mass Index
One way of finding out whether you are a healthy weight is to measure your Body Mass Index (BMI). NHS Choices has a BMI calculator that tells you what your BMI is, based on your height and weight.
You should measure your BMI before you become pregnant. If you are pregnant, or if you’ve recently had a baby, your midwife or GP can give you advice on keeping to a healthy weight.
If your BMI before pregnancy is between 25 and 29.9, you are in the overweight range. If your BMI is 30 or more, you are in the obese range.
What are the risks?
If your BMI was 30 or more before pregnancy, you have a higher risk of:
- needing an emergency c-section
- heavy bleeding after a c-section or vaginal delivery that needs treatment
- problems with your c-section wound, such as the wound opening or infection
- blood clots – you may need to have daily injections of a blood-thinning drug for between one and six weeks after your c-section to reduce this risk
- having a large baby, weighing more than 4kg (8lbs 13oz)
- your baby needing help to breathe after birth.
If you have complications during pregnancy or birth, you may need a longer stay in hospital after your c-section.
Diet and exercise
Eating a healthy diet and keeping active will help you and your baby stay healthy while you are pregnant, and will help you keep to a healthy weight after the birth. Your healthcare team will give you advice on diet and exercise during your pregnancy. Avoid dieting when you are pregnant or breastfeeding as it may harm your baby or affect your milk supply.
There are no UK guidelines saying how much weight you can expect to gain during pregnancy. It will vary from woman to woman. The weight will come from your baby, the amniotic fluid and the extra blood and fluid your body produces, together with body fat.
Keeping active after your c-section will help you recover physically and mentally. This, together with breastfeeding, can help you to manage your weight. Going for gentle walks with your baby is a good way of keeping active while you’re recovering from your c-section. When you are feeling stronger, and don’t have any pain or discomfort, you could try going for brisk walks or swimming. Listen to your body and avoid pushing yourself too hard while you’re recovering from the surgery.
- Dignon A, Truslove T (2013) Obesity, pregnancy outcomes and caesarean section: a structured review of the combined literature. Evidence based midwifery 11(4): 132-137.
- Faucett AM, Metz TD (2016) Delivery of the Obese Gravida. Clinical Obstetrics and Gynecology 59(1): 180–192.
- Marchi J et al. (2015) Risks associated with obesity in pregnancy, for the mother and baby: a systematic review of reviews. Obesity reviews 16: 621–638.
- NHS Choices (2016) [Accessed 9 February 2018] What is the body mass index (BMI)? www.nhs.uk/chq/Pages/3215.aspx
- NICE (2011) Caesarean section. Clinical guideline 132, London National Institute for Health and Clinical Excellence.
- NICE (2010) Weight management before, during and after pregnancy. Public health guideline 27, Manchester National Institute for Health and Clinical Excellence.
ℹLast reviewed on April 24th, 2018. Next review date April 24th, 2021.