Prolactin is a hormone produced by the pituitary gland in the brain. It plays a significant role in regulating many body functions, including ovulation, metabolism and immunity, but its primary purpose is to stimulate the mammary glands to begin milk production. Increased levels of the hormone is crucial to maintaining an adequate milk supply for nursing mothers. When not nursing, however, an imbalance of prolactin can be evidence of a serious health condition requiring medical assessment and treatment.
During pregnancy, a woman’s body starts to produce higher than normal levels of prolactin. This hormonal increase causes the mammary glands to begin preparation for milk production, but elevated levels of the hormone progesterone prevent the breasts from lactating before birth. Progesterone production decreases shortly after giving birth as prolactin continues to increase, stimulated in part by the baby’s first attempts to suckle at the breast, and this allows the breasts to begin lactating.
The Mothering Hormone
Prolactin plays an essential role in facilitating bonding between new mothers and their babies. Prolactin works in conjunction with another hormone, oxytocin, to stimulate the mammary glands to produce milk and release it down into the breast. When mothers breastfeed they often feel deep feelings of attachment, calm, and rushes of contentment or euphoria. These emotional responses are caused, in part, by raised levels of prolactin and oxytocin and they help build enduring connections between mothers and their babies.
High levels of prolactin after giving birth are thought to help a women transition to her role as a mother as well as promoting healthy immune system development in babies. Conversely, low levels of prolactin may contribute to a woman struggling to breastfeed. A deficiency of prolactin may also undermine the deep bonding feelings between a woman and her child. It is helpful, therefore, to aid the body’s production of prolactin before and directly after giving birth.
Prolactin levels peak when labor is allowed to start naturally and they are more likely to remain high if the mother and baby are kept together immediately following delivery. Skin-to-skin contact between mother and child is encouraged and breastfeeding should begin as soon as possible after the baby is born.
Hyperprolactinemia: Too Much of a Good Thing
High levels of prolactin are essential for pregnant women and nursing mothers, but when the body produces too much of the hormone in women who are not pregnant or breastfeeding, it can be a sign of a serious health condition called hyperprolactinemia. This hormone imbalance can occur for multiple reasons. Sometimes, benign tumors on the pituitary gland called prolactinomas cause hyperprolactinemia, or the condition can result from complications related to kidney or liver disease, hyperthyroidism, or anorexia nervosa.
Common symptoms of hyperprolactinemia include headaches, abnormal facial hair growth, acne, visual impairment, an irregular or absent menstrual cycle, infertility, discomfort during sexual intercourse, and/or lactation in the absence of childbirth or breastfeeding. Hyperprolactinemia is a serious health condition that can affect both men and women. Its symptoms should not be ignored and if properly diagnosed and treated, the condition usually reversible.
Testing and Treatment for Hyperprolactinemia
A simple blood test can check for hyperprolactinemia. A normal range for women who are not pregnant is <25 ng/mL. For women who are pregnant, an appropriate number is between 34 to 386 ng/mL. Prolactin levels vary throughout the day and some medications can raise levels, so it is important to discuss the test with a healthcare provider prior to testing.
Hyperprolactinemia is a highly treatable condition. Depending on the cause of the prolactin imbalance, hormone levels can be restored with medication and behavioral changes such as modifying diet and exercise. If the hyperprolactinemia is caused by prolactinomas, surgery might be necessary if the tumors cannot be treated successfully with medication. People struggling with hyperprolactinemia are also encouraged to decrease their stress levels, and maintain consistent blood sugar levels.
Prolactin Levels and Your Health
Appropriate prolactin levels play a critical role in a person’s overall health. In women who are are pregnant or nursing, increased levels are necessary for adequate milk production, however, if levels are raised in the absence of pregnancy or breastfeeding, a serious health condition may be the cause. The good news is, testing for an imbalance of prolactin is easy and there are many effective treatment options.