[Easy to remain overweight after pregnancy].

For some women pregnancy is a trigger factor for developing overweight and obesity. 73% of patients at the Obesity Unit, Huddinge University Hospital, indicated that they had retained more than 10 kg after each of their pregnancies; for this subgroup weight development after pregnancy was of obvious importance for their future health. However, in most studies mean weight retention after pregnancy is modest: 0.5-3.5 kg up to one year after delivery. Numerous studies have analysed factors explaining weight development after pregnancy and delivery, with a wide range of subjects, but overall it has been surprisingly difficult to identify strong predictors for weight development. The strongest factor is weight gain during pregnancy, but smoking cessation, a sedentary lifestyle and socio-economic factors also play a role. Pregnancy and weight development are intertwined in a complex pattern, which includes a change in lifestyle factors, such as eating behaviour, physical activity, smoking cessation and degree of lactation, but which are still not fully understood.