It’s a well-known fact that carrying too much weight is a risk factor for many diseases and illnesses. However, new research shows that an increase in pregnancy obesity may be responsible for poor outcomes for mums and babies.
Obesity has become an increasing problem for Australians with almost two thirds of Australian adults now carrying excess weight and the proportion of obese adults continuing to rise.
Worryingly, this trend of increasing obesity includes pregnant women who are putting their own health at risk, and that of their unborn children, according to a new research study.
Researchers analysed data from more than 42,500 first-time mothers between 1990 and 2014 and found there was a major increase in the number of pregnant women who were overweight or obese. During this time, there had also been a steady increase in poor health outcomes due to excessive weight during pregnancy.
How does excess weight affect pregnancy, birth and child health?
The classification of ‘overweight’ or ‘obese’ depends upon a measurement called Body Mass Index (BMI). It’s calculated by dividing your weight in kilograms by height in metres squared (kg/m2). A BMI of 25-29.9 is considered overweight, while a BMI of 30 or more is classified as obese.
Carrying too much weight increases the risks for a number of pregnancy complications, including:
- miscarriage, stillbirth and recurrent miscarriage
- pre-eclampsia (characterised by high blood pressure, and damage to organs)
- gestational diabetes
- heart dysfunction
- sleep apnoea (a potentially serious sleep disorder in which breathing repeatedly stops and starts)
- a difficult vaginal delivery or obstructed labour
- birth trauma
- haemorrhage (serious bleeding)
- the need for a C-section and the risk of associated complications, such as wound infections.
Being overweight or obese increases the risk to the baby of:
- having a high birth weight, which increases the risk of metabolic syndrome and childhood obesity
- developing birth defects – it’s also harder to detect these conditions in overweight and obese mothers.
Does reducing weight make a difference?
Researchers of the study believe that losing weight would reduce the number of pregnancy complications. They found that if overweight or obese women moved down one BMI category, they could have avoided:
- 0% of pre-eclampsia
- 9% of high birth weight babies
- 2% of gestational diabetes
- 5% of caesarean deliveries
- 1% of birth weights greater than the 90th percentile for gestational age
- 1% of stillbirths
- 8% of post-partum haemorrhage
- 5% of admissions to the special care nursery
- 8% of premature births
- 8% of fetal abnormality.
What should women do?
According to the study, once a woman who is overweight or obese becomes pregnant, it may be too late to reduce the risks of pregnancy complications, although introducing regular exercise and dietary changes may help to avoid excessive weight gain. The woman should work closely with her doctor to manage her health and that of her baby.
For women planning to have a baby, it’s wise to have a check-up with the doctor first to determine any underlying health issues — including carrying too much weight — that may impact the pregnancy and the health of the baby. This is also a good time for the doctor to review any medication is being taken.
Health professionals also recommend women should:
- stop smoking
- stop drinking alcohol and taking other social drugs
- reduce caffeine intake
- follow a healthy diet and focus on eating freshly cooked and prepared food
- take folic acid for at least one month before conception and for the first three months of pregnancy
- take an iodine supplement pre-pregnancy, in pregnancy and when breastfeeding
- develop a good exercise routine
- ensure rubella and varicella (chickenpox) immunity
- have a dental check, as it’s quite common to experience dental problems during pregnancy.
The best chance of a healthy pregnancy and a healthy baby relies on the mum taking good care of herself prior to falling pregnant.