Efficacy of micronized progesterone-based preparations used to prevent placental insufficiency: an experimental study

Introduction: Progestogen-based drugs have anti-ischemic, antispasmodic, and immunomodulatory effects. Therefore, studying the effect of micronized progesterone (MP) on the inflammatory process in the placenta is of great importance. Materials and Methods: Four observation groups were formed: Control Group 1 (CG1, n=6) – intact rats; Control Group 2 (CG2, n=6) – pregnant rats with simulated placental insufficiency; Experimental Group 1 (EG1, n=7) – rats with simulated placental insufficiency that received MP dosage 20 mg/day; Experimental Group 2 (EG2, n=7) – rats with simulated placental insufficiency that received MP dosage 40 mg/day. An analysis of the placenta, anthropometric parameters of the fetuses, and physical development parameters of the offspring was conducted. Histological and immunohistochemical analyses of the placentas were performed. Results and Discussion: Miscarriage was observed in 16% of animals from CG2, which did not receive MP therapy, compared to rats from CG1. In intact CG1 and EG1 rats, the course of pregnancy, parturition, and developmental parameters of the pups were within physiological norms. In rats from EG2, the course of pregnancy and parturition, the condition of rat pups did not differ from the physiological norm; however, one rat developed convulsions during birth. Immunohistochemical analysis revealed reduced inflammatory manifestations in the placenta of rats treated with MP, compared to animals from the control group that did not receive pharmacological correction. Conclusion: Under experimental conditions, MP can prolong pregnancy to physiological norms and have a positive effect on the physical development of the offspring.