• endocrinology;
  • human;
  • LHRH;
  • prenatal;
  • vomeronasal organ

The purpose of this study was to describe in 49 normal human prenatal specimens. 15–156 mm crown-rump length (CRL), the histomorphological development of the bilateral vomeronasal organ localized in the mucosa of the nasal septum. In addition, immunohistochemical localization of luteinizing hormone-releasing hormone (LHRH) was undertaken. The material was classified into five developmental stages (NAS I/V), based on the morphology of the nasal cavity. The vomeronasal organ was visible in stages NAS II, III and IV, corresponding to 21–102 mm CRL. Positive immunohistochemical reaction for LHRH neurons was pronounced in the vomeronasal organ in NAS II and III. corresponding approximately to fetal ages 8–12 gestational weeks (21-51 mm CRL). The study demonstrates in normal human prenatal material that LHRH can be recorded in the bilateral vomeronasal organs during approximately 4 weeks of intrauterine life.