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, focusing on gestational outcomes and offspring development. Administering the 5α-reductase inhibitor finasteride from gestational days 17–21 significantly reduced gestational length and litter size compared to controls. Offspring exposed to finasteride showed impaired object recognition and altered neuroendocrine profiles, with decreased hippocampal 3α,5α-THP content and increased progesterone in the medial prefrontal cortex and diencephalon. These findings suggested that 5α-reduced progesterone metabolites were crucial for maintaining normal gestation and cognitive function in offspring, highlighting the potential impact of prenatal stressors on developmental outcomes.