Development of the Fetal Duodenum: A Postmortem Study
Fetal Diagnosis and Therapy
Introduction Small intestines occupy the middle and lower zones of the abdominal cavity and the duodenum constitutes the first part of the small intestines. In adults, the duodenum pursues a U-shaped or semi-circular course around the head of the pancreas  . The duodenum develops at the beginning of week 4 from the caudal end of the foregut, cranial end of the midgut, and the splanchnic mesoderm which is the connection between these two endodermal parts. Two parts of the duodenum fuse just
... uodenum fuse just distal to the orifice of the common bile duct. The duodenum develops rapidly, assumes a C-shape, making an arch in the anterior direction. As the stomach rotates, the duodenal loop rotates rightwards, attaches to the posterior body wall and secondarily becomes retroperitoneal [2, 3] . The development of the duodenum during the fetal period, from 9 weeks of gestation till birth, is critical since abnormal shapes are associated with congenital malformations [3, 4] . Moreover, it has been argued that duodenal pathologies observed in adults may be related to fetal development and certain pathologies started during the fetal life. Therefore, early diagnosis of these pathologies is claimed to be quite important    . When we searched for studies on the development of the duodenum, we failed to find any detailed publication on the fetal development of the duodenum. Studies were mostly related to the pathologies of the duodenum  . Abstract Objective: To gather detailed morphometric data to be able to assess fetal development of the duodenum and its morphology. Material and Method: The present study was carried out on 222 human fetuses (114 males, 108 females) aged 9-40 weeks of gestation with no external pathology or anomaly. Fetuses were grouped based on gestational weeks, months and trimesters. Once general external measurements of the fetuses were carried out, the abdominal wall was dissected. The relationships between the duodenum and surrounding structures and its localization were determined. Morphometric data on height, width, length and diameters were gathered. Findings: Means and standard deviations of all parameters were calculated for each ges tational week, month and trimester. There were significant relations between measured parameters and gestational age (p ! 0.001). There were no sex differences in parameters (p 1 0.05). All data were compared with previous studies and discussed. Conclusion: Data obtained in this study will contribute to other studies carried out in obstetrics, perinatology, forensic medicine and fetal pathology departments, aimed at identifying anomalies, pathologies and variations of the duodenum and treatment of such cases.