Prolactin
In Latin this means ‘for milk’ and it’s the pituitary hormone that helps produce breast milk in lactating women. In some women this Prolactin number is high and interferes with fertility. That’s why women who are breastfeeding are less likely to become pregnant. The high number can come from a variety of sources and is sometimes due to a small and harmless growth on the pituitary that can be treated with medicine.