The Prolactin Family of Hormones as Regulators of Maternal Mood and Behavior

Abstract

Transition into motherhood involves profound physiological and behavioral adaptations that ensure the healthy development of offspring while maintaining maternal health. Dynamic fluctuations in key hormones during pregnancy and lactation induce these maternal adaptations by acting on neural circuits in the brain. Amongst these hormonal changes, lactogenic hormones (e.g., prolactin and its pregnancy-specific homolog, placental lactogen) are important regulators of these processes, and their receptors are located in key brain regions controlling emotional behaviors and maternal responses. With pregnancy and lactation also being associated with a marked elevation in the risk of developing mood disorders, it is important to understand how hormones are normally regulating mood and behavior during this time. It seems likely that pathological changes in mood could result from aberrant expression of these hormone-induced behavioral responses. Maternal mental health problems during pregnancy and the postpartum period represent a major barrier in developing healthy mother-infant interactions which are crucial for the child's development. In this review, we will examine the role lactogenic hormones play in driving a range of specific maternal behaviors, including motivation, protectiveness, and mother-pup interactions. Understanding how these hormones collectively act in a mother's brain to promote nurturing behaviors toward offspring will ultimately assist in treatment development and contribute to safeguarding a successful pregnancy.

The effect of yoga training on postpartum prolactin and oxytocin levels in primipara women

“…Prolactin has a major role in lactogenesis, increased prolactin secretion being essential for successful breastfeeding [ 42 ]. This increase in mean prolactin levels is in accordance with studies that showed that prolactin production can be increased through stimulation of the chest area or by avoiding stress and anxiety [ 10 , 43 ]. In this study, yoga practice was a mind–body–soul exercise based on breathing exercises (pranayama), physical postures (asana), and relaxation, focused on the area around the chest and breasts on the basis of complete respiration.…”

High fat diet‐induced maternal obesity in mice impairs peripartum maternal behaviour

“…It has been shown in rats that shortly prior to parturition, prolactin levels rise and during lactation, suckling induces prolactin secretion to promote milk production. Prlr activation during pregnancy has been proposed to modulate many functions, including metabolic regulation, 18 behavioural modulation [19][20][21] and glucose regulation, 22,23 to adapt the body to the state of pregnancy and prepare for the demands of lactation. 24 For example, we have previously shown that Prlr activity in the medial preoptic area (MPOA) is critical for the onset of nursing behaviour in postpartum mice.…”

The role of maternal hormones in regulating autonomic functions during pregnancy

“…Pregnancy is associated with a plethora of changes that serve to safeguard the healthy development of the offspring. For example, physiological adaptations include food intake and energy expenditure alterations to meet the increasing metabolic demand of the growing foetus while behavioural changes occur to nurture and protect the young 1,2 . The unconscious physiological processes that are usually considered under the control of the autonomic nervous system are also dramatically altered during pregnancy, and these changes contribute to healthy foetal growth and aiding safe delivery of the offspring.…”