High Prolactin and Pregnancy Loss: Can Hormonal Imbalance Affect Fertility and PMOS?

When a woman faces difficulty conceiving or experiences repeated pregnancy loss, doctors usually investigate several possible factors, including the uterus, embryo quality, ovarian function and hormonal health. One hormone that may also require attention is prolactin, which is produced by the pituitary gland and plays an important role in breast milk production. Prolactin naturally rises during pregnancy and breastfeeding, but persistently elevated levels outside these periods are known as hyperprolactinaemia. High prolactin can interfere with the hormonal signals involved in ovulation, potentially causing irregular or absent periods and making conception more difficult. Some women may also experience unexpected milk-like breast discharge, although symptoms are not always present.

The relationship between high prolactin and recurrent pregnancy loss, however, is not straightforward. Clinical guidance notes that evidence linking hyperprolactinaemia to repeated pregnancy loss has been inconsistent, and routine testing is not universally recommended in women without symptoms. Other established causes, including chromosomal abnormalities, uterine problems, thyroid disorders and certain immune or blood-clotting conditions, may also contribute to recurrent pregnancy loss. If prolactin is found to be elevated, doctors may repeat the test and assess possible causes such as hypothyroidism, medication use or a prolactin-producing pituitary tumour. Treatment, when a genuine hormonal disorder is confirmed, depends on the underlying cause and may include medicines that lower prolactin levels.