We identified that women who lost two to three kilograms of weight in that third trimester of pregnancy improve their glucose levels quite quickly and also had babies who were a healthier size. We know that this is safe and beneficial for mothers with gestational diabetes and their babies and is likely to have long-term benefits. Hello, my name is Professor Claire Meek. I work at the Leicester Diabetes Centre as professor of Chemical Pathology and Diabetes in Pregnancy. My research group aims to focus on healthy moms, healthy babies, and healthy families in the context of diabetes and pregnancy. And my special interest is in helping women maintain healthy weight gain during pregnancy. In the past, there's been lots of concern about undernutrition in women approaching pregnancy and because of that, common mantras such as the need to eat for two has resulted in a situation where many women are encouraged to gain excessive amounts of weight during pregnancy. This is no longer healthy in a population with rising rates of obesity. And therefore, the role of our work is to help understand how much weight is the right amount of weight to gain during pregnancy? And how can we help women maintain a healthy weight before, during, and after pregnancy? Most authorities internationally use the guidance prescribed by the Institute of Medicine, which was identified around three decades ago in the US. This suggests that women with overweight and obesity should gain a smaller amount of weight during pregnancy, compared to women entering pregnancy with a BMI in the lean range. So, for example, women with obesity are recommended to gain five to nine kilos of weight during pregnancy. However, there are increasing concerns that actually nine kilograms of weight gain might be too much for many women with obesity, particularly those women entering with a higher BMI. So, we recently ran a DiGest trial, that's a Dietary Intervention in Gestational Diabetes. It's a randomised controlled trial of a reduced calorie diet in women with gestational diabetes. And women were randomised to receive either 1,200 calories or 2,000 calories per day from diagnosis to the end of pregnancy at delivery. We identified that women who lost two to three kilograms of weight in that third trimester of pregnancy improved their glucose levels quite quickly and also had babies who were a healthier size. Importantly, we also found there were benefits to women's postnatal HbA1C, which was lower in the group who had lost weight. So, following the results of the DiGest trial, we know that a small amount of weight loss in the third trimester of pregnancy is safe and beneficial for mothers and babies in the context of gestational diabetes. However, there are still many unanswered questions about what is a healthy level of weight gain throughout the whole pregnancy and even if weight loss overall could be beneficial. We have some data from our DiGest trial suggesting that modest amounts of weight loss throughout the whole pregnancy could also be beneficial. However, it's really key that avoiding excessive gestational weight gain is one of the most important ways we can improve pregnancy outcomes for women with diabetes or obesity. My take home messages would be that avoiding excessive gestational weight gain is absolutely crucial if we want to improve outcomes for mothers and babies in the context of diabetes or obesity in pregnancy. However, increasingly we can actually benefit from small amounts of weight loss in the third trimester for women with gestational diabetes. We know that this is safe and beneficial for mothers with gestational diabetes and their babies and is likely to have long-term benefits.