What are the benefits of including some types of fish and shellfish in one’s pregnancy diet, and why must other types of fish and shellfish be avoided during pregnancy?

Some consumption of fish needs to be cut back to about once a week or eliminated completely because some fish contain high amounts of mercury. That is obviously something you don't want to be consuming while pregnant and/or breastfeeding. Some benefits of fish could be the nutrients, and its a lot healthier than eating beef all the time. Hope this helps.