By Andrew M. Seaman (Reuters Health) – Women who take part in exercise, diet programs or a combination of the two during pregnancy can prevent excessive weight gain, according to a fresh review of past research. The review incorporates dozens of new studies to update a previous review that did not find enough evidence to support the use of diet and exercise during pregnancy. After including the new studies, the new review found “high-quality evidence” to show diet, exercise or both can reduce the risk of excessive weight gain during pregnancy, write the researchers in The Cochrane Library.