The pituitary gland is at the base of the brain. It makes and stores many hormones, including prolactin, which stimulates milk production. It doubles in size during pregnancy.
If a mother has a hemorrhage and her blood pressure falls quickly, the front part of the pituitary gland may not receive enough blood and could be temporarily or permanently damaged, resulting in low levels of one or more hormones. Permanent damage in these circumstances is called Sheehan syndrome.
A major drop in blood pressure can result in the milk coming in late. It can also decrease the milk supply. This may be temporary if the effect on the pituitary gland is mild and reversible. Mothers with Sheehan syndrome are most likely to have a permanently low milk supply (Flood et al. 2018). If the damage to the pituitary is severe, they may have no milk at all. We have seen this once in our clinic.
Mothers with Sheehan syndrome may develop health problems including:
- Irregular periods or no periods
- Low thyroid hormone levels
- A poorly functioning adrenal gland
- Low levels of sodium in the blood
It may take a long time, even years, for Sheehan syndrome to be diagnosed (Ramiandrasoa 2013).
Alternatively some mothers develop significant symptoms shortly after the birth of the baby. These can include severe headache, nausea, vomiting, eye pain cause by light, and confusion (Varutti 2019).
Mothers with a history of large blood loss or a drop in blood pressure during or after delivery and a low milk supply should see their health-care providers. Sheehan syndrome is diagnosed with blood and radiological tests.