Overweight and obesity pre pregnancy or during pregnancy is associated with an increased risk for maternal obstetric and fetal complications. Diet is one modifiable risk factor that women may be motivated to improve. General healthy eating guidelines, micronutrient sufficiency and macronutrient quantity and quality are important nutrition considerations pre and during pregnancy.

With regards to specific nutrients, health authorities have recommendations for folate and/or iodine supplementation; but not consistently for iron and omega-3 despite evidence for their association with health outcomes. There are modest additional requirements for energy and protein, but not fat or carbohydrate, in mid-late pregnancy.

Diet indices and dietary pattern analysis are additional tools or methodologies used to assess diet quality. These tools have been used to determine dietary intakes and patterns and their association with pregnancy complications and birth outcomes pre or during pregnancy.

Women who may unnecessarily resist foods due to fear of food contamination from listeriosis and methylmercury may limit their diet quality and a balanced approached is required. Dietary intake may also vary according to certain population characteristics.

Additional support for women who are younger, less educated, overweight and obese, from socially disadvantaged areas, smokers and those who unnecessarily avoid healthy foods, is required to achieve a higher quality diet and optimal lifestyle peri conception.