Remedies: Supplementing during pregnancy

Introduction
This is something I found in an email about supplementation during pregnancy. I have recorded this here for my own information.

Extract of email
My daughter has always been interested in natural health and has taken supplements for years. She's about to have her first child and plans on breast-feeding. Should she keep taking supplements while she's nursing?

Dr. Wright: Nursing or soon-to-be-nursing mothers should certainly be taking supplements, especially folic acid, calcium/magnesium, a high quality multiple vitamin-mineral, and iron. There is one nutrient, however, that your daughter does need to limit: Even "medium-high" quantities of vitamin B6 could suppress prolactin secretion. Prolactin is the principal pituitary hormone that stimulates milk formation in nursing mothers. Even though this fact was documented years ago, it still isn't as well known as it should be.

Your daughter should check to be sure that her total intake of vitamin B6 (including pyridoxine and pyridoxal phosphate) isn't higher than 25 milligrams a day. The lowest amount necessary to "shut off" prolactin is likely 50 milligrams daily or more -- but there's no point in risking a problem.