Vegetarian women were also 25 percent more likely to have anxiety compared with women who had consumed some fish and meat.

Researchers from the Federal University of Pelotas recruited 9,500 women for the study, grouping the women based on their dietary patterns. At 32 weeks of pregnancy, the women completed questionnaires about their anxiety levels.

"In order to have a healthy pregnancy, women need to follow a healthy diet, and not something special for pregnancy," study author Juliana Vaz said. Vaz recommends a diet rich in whole grains, vegetables, meat, poultry, and fish.

The study is published online in the journal Plos One.