Md. Ashraful Azim^1,, Mohammad Ashfaqur Rahman¹, Farhana Karim²

Vasculosyncytial membrane is the only structural barrier between maternal and fetal circulation found in the wall of the terminal chorionic villi. Its normal function is essential for the survivability of a growing fetus. Understand the role of the placenta during fetal growth; it is necessary to know changes of vasculosyncytial membrane with gestational age. This study carried out on total ninety products of conception and placenta, and all the collected samples divided into three groups. One group included 30 products of conception from the first-trimester pregnant woman, and another two groups included a total of 60 placentae from the second and third-trimester pregnant woman. All the placentae were fixed in 10% formol saline for 48 hours, after fixation two tissue blocks taken from each specimen. After tissue processing and staining, the histomorphological changes studied among three groups under the light microscope — statistical analysis done by ANOVA test. In the first-trimester placenta, vasculosyncytial membrane was absent. In the second trimester, it ranged from 5.1 – 15.00 μm and the mean ± SD was 8.54 ± 0.84 μm. In the third trimester, it ranged from 1.90 – 4.70 μm, and the mean ± SD was 3.12 ± 0.73 μm. Vasculosyncytial membrane thickness significantly reduced with the aging of the placenta. The study findings suggest placental tissue continued to grow until term. Rate of exchange of gas and other nutrients supposed to be more with the advancement of pregnancy.

vasculosyncytial membrane, chorionic villi, diffusion distance, placenta