Galectins: guardians of eutherian pregnancy at the maternal–fetal interface

Galectins are multifunctional regulators of fundamental cellular processes. They are also involved in innate and adaptive immune responses, and play a functional role in immune–endocrine crosstalk. Some galectins have attracted attention in the reproductive sciences because they are highly expressed at the maternal–fetal interface, their functional significance in eutherian pregnancies has been documented, and their dysregulated expression is observed in the ‘great obstetrical syndromes’. The evolution of these galectins has been linked to the emergence of eutherian mammals. Based on published evidence, galectins expressed at the maternal–fetal interface may serve as important proteins involved in maternal–fetal interactions, and the study of these galectins may facilitate the prediction, prevention, diagnosis, and treatment of pregnancy complications.