While it is not a condition that many prospective parents may have heard of, insufficient glandular tissue (IGT), also known as mammary hypoplasia, can have a significant impact on breastfeeding. The condition is not easy to diagnose prior to giving birth, so women may not know they have it until they begin breastfeeding.

An IGT diagnosis means you have fewer glands and ducts that are able to produce milk inside the breasts. The condition is caused by the lack of development of glandular tissue—tissue that produces milk—in the breast during pregnancy, according to Jamie Chia Lin, M.D., a Los Angeles-based OB-GYN.

Lin explained that this condition can be caused by several factors, including genetic makeup, disorders of the endocrine system or a lack of the hormone prolactin, which stimulates milk production after childbirth. Surgeries such as breast enhancements can sometimes disrupt breast tissue and increase the risk of IGT, she added.

Diagnosing IGT before pregnancy

While diagnosing IGT before birth is uncommon, there are