Advice on why weight matters during pregnancy and after birth is explored in new guidance published by the Royal College of Obstetricians and Gynaecologists (RCOG).
The majority of women who are overweight (BMI > 25) will have a straightforward pregnancy and birth.
However, being overweight does increase the risk of complications for mother and baby. With increasing BMI, the risks become gradually more likely, being much higher for women with a BMI of 40 or above.
Risks associated with a raised BMI include thrombosis, gestational diabetes, high blood pressure and pre-eclampsia. Risks to the baby include miscarriage, neural tube defects, larger birth weight, stillbirth and obesity and diabetes later in life.
During labour and birth there is a higher risk of premature birth, shoulder dystocia, emergency caesarean section and post-partum haemorrhage.
The new patient information looks at how to reduce the risks and what extra care overweight mothers should be offered during pregnancy and birth.
The guidance recommends that women work together with their healthcare professionals to reduce any risks. This includes eating a healthy diet and watching the portion size of meals. In general women do not need extra calories for the first two thirds of pregnancy and it is only in the last 12 weeks that women need an extra 200kcal a day states the guidance.
The new advice also covers exercise in pregnancy, vitamin supplements, planning for labour and birth, after birth care and planning for a future pregnancy.
Chair of the RCOG’s Patient Information Committee, Philippa Marsden, said:
“This new advice gives women information about the risks of being overweight during pregnancy and giving birth, but more importantly focuses on how women can work together with their health care team to reduce these risks. It also details the extra care a woman should have during her pregnancy if she has a raised BMI.
“Trying to lose weight by dieting during pregnancy is not recommended – even if you are obese – as it may harm the health of your unborn baby. However, by making healthy changes to your diet you may not gain any weight during pregnancy and you may even lose a small amount.
“Healthcare professionals can also help you with losing weight if you are planning for a future pregnancy or after you have had your baby.”