Prolactin is a hormone that is made in the pituitary gland. This hormone helps to stimulate milk production within women, once they have delivered a baby. When a woman begins breastfeeding it is expected for them to have higher levels of prolactin. It is very common for these high levels to interfere with a woman’s ovulation. This is a common factor as to why many newly breastfeeding mothers do not ovulate and do not often get pregnant during this time period. Prolactin levels remain high for the beginning of the breastfeeding process, yet they begin to lower as time goes on.
High Prolactin Levels and the Consequences
If a woman that is not pregnant and not breastfeeding has high levels of prolactin, this could cause an issue with ovulation and menstruation. Research shows that these high levels may cause infertility. Much like women who are newly breastfeeding, high levels of prolactin often cause a lack of ovulation all together. In some cases it is possible that high levels of prolactin could affect a woman’s ovulation cycle intermittently. This could make a woman’s cycle unpredictable, which may cause issues when it comes to trying to conceive.
It is also possible that instead of affecting a woman’s ovulation, high levels of prolactin would interfere with a woman’s progesterone levels after ovulation. This could cause issues for an embryo during the implantation process. High levels of prolactin can also stop the production of the hormone estrogen. When estrogen is not being produced in the body, this could affect a woman’s menstrual cycle, cause vaginal dryness, or lessen her sex drive.
Reasons Behind High and Low Levels of Prolactin
High Levels
When a woman, that is not pregnant or breastfeeding, has prolactin levels between 30 ng/mL and 200 ng/ml these are considered moderately high. Research shows that there can be many causes behind higher levels of prolactin such as:
- Hypothyroidism
- Polycystic Ovary Syndrome (PCOS)
- Liver disease
- Kidney disease
- Pituitary disorders
- Anorexia nervosa
- Prolactinoma (Pituitary Adenoma)
- Medications
- Stress
Low Levels
It is common for women to have low levels of prolactin when not pregnant or breastfeeding. However, research shows that prolactin deficiency can occur. Prolactin deficiency is also known as hypoprolactinemia. This can occur due to an autoimmune disease, deficiency in pituitary hormone production, growth hormone deficiency, hypothyroidism, or the anterior pituitary. Hyperprolactinemia is often associated with ovarian dysfunction, where the ovaries do not release eggs regularly and do not produce enough sex hormones for fertility.
Medications such as dopamine and levodopa can also cause low levels of prolactin. In some cases, hypopituitarism has also been found to be the reasoning behind low levels of prolactin.
The Importance of Prolactin to Female Fertility
High prolactin levels may cause infertility. Fluctuating prolactin levels can make a woman’s ovulation and menstrual cycle irregular or nonexistent. There are many underlying conditions that may be the reason behind higher prolactin levels in women. It is important to speak to a medical provider when experiencing fluctuation within prolactin levels. When experiencing infertility, testing your prolactin levels may help to identify an underlying additional medical condition at hand.
