What causes girls' nipples to be inverted?

What are the reasons for inverted nipples in girls? We should also pay attention to understanding this problem, because if a woman has inverted nipples, the impact will be relatively large. The reasons include primary hypoplasia of the nipple and areola smooth muscles, or primary hypoplasia of the lactiferous duct itself. Therefore, as parents, we should do a good job of prevention when our children are still young.

1. Primary smooth muscle dysplasia of the nipple and areola

The nipple has 15 to 20 openings of lactiferous ducts, which are surrounded by smooth muscle fibers. The inverted nipple is pulled inward by the muscle fiber bundles that surround the lactiferous ducts and insert into the nipple dermis. The texture of these muscle bundles is significantly different from that of the lactiferous ducts.

Second, primary lactiferous duct hypoplasia

Hypoplastic lactiferous ducts fail to ductalize and appear as cords. The lack of supporting tissue under the nipple is also the cause of inverted nipples.

3. Other factors

It is usually secondary to breast tumors, inflammation, trauma or traction of scars after breast surgery, or sagging breasts.

Pathogenesis

1. Pathogenesis: Primary nipple inversion is a developmental malformation. In the late stage of nipple development, the ectoderm at the starting point of the original breast bud becomes concave to form a nipple dimple. Later, the underlying mesenchyme proliferates and bulges outward to form a nipple. When this process stagnates, the nipple becomes inverted. One-quarter of patients have bilateral disease. Secondary nipple inversion is mostly caused by the traction of the nipple by pathological tissue in the breast, which makes the nipple unable to protrude. It is often one of the clinical signs of breast inflammation, especially breast cancer.

2. Pathological degree: Nipple inversion can be divided into 3 degrees according to the depth of its retraction:

First degree: The nipple is slightly retracted and there is a groove at the base of the nipple.

Second degree: The nipple is moderately retracted and has sunk into the areola.

Third degree: The nipple is severely retracted, folded and concave, like an inverted glove. This is the result of cancer cells invading the areola area and the contraction of fibrous tissue.