2025 Theses Doctoral

Mother Knows Best: The Role of Olfactory Cues in Postpartum Maternal Care

Andreu, Valentine

The transition into motherhood is characterized by profound changes in the brain and body. During pregnancy and after birth, the reproductive, endocrine, and nervous systems undergo significant modification to support the growth and care of offspring. Among these changes, sensory systems also adapt to meet the demands of motherhood. While the olfactory system plays a critical role in pup retrieval and nesting behaviors in dams, how the olfactory system adapts during motherhood remains unclear.

Using odor preference testing, we have demonstrated that first-time mothers develop a specific preference for pup urine following parturition and early postpartum care, which is not observed for other social or neutral odors. This preference is absent in late-pregnant females, first-time mothers separated from their pups after parturition, and virgin females exposed either to pups or to pup urine. This finding suggests that the development of pup urine preference requires both internal (hormonal) and external (chemosensory) cues to develop.

Finally, gas chromatography-mass spectrometry analysis identified specific volatile compounds in pup urine that may drive this behavior. These findings may provide valuable insight into how the transition to motherhood influences the sense of smell, with chemosensory cues playing a key role in shaping maternal responses and enhancing olfactory-guided behavior.