Inhibition of 5α-Reductase Activity in Late Pregnancy Decreases Gestational Length and Fecundity and Impairs Object Memory and Central Progestogen Milieu of Juvenile Rat Offspring

The study investigated the effects of inhibiting 5α-reductase activity during late pregnancy in Long-Evans rats. It was found that administering the 5α-reductase inhibitor finasteride from gestational days 17-21 significantly reduced gestational length and the number of pups per litter. Additionally, prenatal exposure to finasteride impaired object recognition and altered neuroendocrine function in juvenile offspring, particularly affecting females by decreasing hippocampal 3α,5α-THP content and increasing progesterone concentration in the medial prefrontal cortex and diencephalon. These findings suggested that 5α-reduced progesterone metabolites play a crucial role in maintaining gestation and influencing cognitive and neuroendocrine development in offspring.