Getting pregnant when you are an ideal healthy weight is much better for you and your baby. If you are overweight and thinking of pregnancy it’s good to address your weight before you start trying to conceive.
The weight may have crept on over the years or you may still be carrying ‘baby weight’ from previous children. Whatever the reason, you’ll have more physical energy and be less at risk of medical problems in pregnancy if you are a healthy weight at the start.
Harder to get pregnant
There’s evidence that being overweight will hamper your efforts to fall pregnant. Being overweight can affect your hormones and ovulation patterns, too.
If you’re in a healthy weight range, with a BMI between 18.5 and 24.9, you may have a better chance of becoming pregnant, according to the NHS.
If your BMI is 25 or over, you are overweight. With a BMI of 30 or more, defined as being obese, your chance of a successful conception decreases.
A 2008 study in the Netherlands found that in women who were less fertile than normal, for every BMI value over 29, the chance of pregnancy fell by 4%. That's around the same reduction in fertility as an additional year of age.
Research also shows that the average wait for pregnancy for healthy weight women was 3 months, but being overweight delayed it for up to 8 months.
Risks of being overweight
The higher your BMI the more likely it is that you may develop health problems in pregnancy. With a BMI over 30 you’re 3 times more likely to develop gestational diabetes than women who are below that BMI. Having pregnancy-related diabetes increases your risk of developing diabetes later. Having gestational diabetes will increase the weight of your baby, increasing the risk of a difficult birth for both of you. You also have a greater risk of high blood pressure, pre-eclampsia and blood clots if you are overweight or obese.
"Research suggests that babies whose mothers are overweight during pregnancy are more likely to be overweight themselves, and are at higher risk of serious health conditions later in life such as heart disease, type 2 diabetes and some cancers," says Helena Gibson-Moore, nutrition scientist and spokesperson for the British Nutrition Foundation.