Anatomical development of urinary bladder during the fetal period.

The aim of this study was to determine the development, location, and size of the urinary bladder during the fetal period. The study was performed on 149 human fetuses between 9 and 40 weeks of gestation. The location of the urinary bladder with respect to transverse plane between the highest point of pubic symphysis and the sacral promontory and median sagittal plane was first determined. The dimensions and the angle of the urinary bladder were measured, and bladder shapes were determined. In addition, the edges of the vesical trigone were measured. There was no significant difference between sexes for any of the parameters (P > 0.05). A significant correlation was observed between all parameters and gestational age (P < 0.001). The urinary bladder was located above the transverse plane in most of the cases (83%) and in the median sagittal plane in every case. It was determined that the angle of bladder did not change and the mean value of the angle was 151 degrees during the fetal period. Bladder was categorized into four different shapes (ellipsoid, round, cuboid, and triangular), and the most common shape found during the fetal period was cuboid. The vesical trigone was an isosceles triangle during the fetal period. The new data provided by this study will enable evaluation of the development of the fetal urinary bladder, and should be useful in several fields such as anatomy, fetopathology, medical imaging, obstetrics, and pediatric urology.

Anatomical development of the fetal uterus.

OBJECTIVE: The objective of this study was to gather data on the morphology of the uterus during its development, to provide detailed information regarding the neighboring structures and its variations using anatomical dissections. STUDY DESIGN: Eighty uteri acquired from female fetuses aged 10-40 weeks of gestation were used in this study. Firstly, the relationship between the fetal uterus and the linea terminalis and the position of the uterus within the pelvic cavity was noted. Then the distance between the fundus of the uterus to the promontory and pubic symphysis were measured. Fetal uteri were classified according to their physical appearances. Finally the lengths of the corpus and cervix in three planes and the anteflexion angle were measured. RESULTS: During the fetal period, the fundus of the uterus was above the linea terminalis in 94% and below it in 6% of the cases. The distance between the fundus of the uterus and the promontory significantly correlated with the distance between the fundus of the uterus and the pubic symphysis (p<0.001). This was true for the correlation between the gestational age and the orthogonal lengths of the uterine corpus and cervix (p<0.001). As the gestational age advanced, the anteflexion angle was noted to reduce from 177 degrees to 120 degrees . The shape of the uterus was either cylindrical, pear-shaped, heart-shaped or hourglass-shaped during the fetal period. CONDENSATION: We believe that the data obtained through dissections of the human fetuses in this study will help identifying uterine developmental variations, anomalies and pathologies and will contribute to the studies carried out in obstetrics, perinatology, forensic medicine and fetal pathology departments.