Lecture 12 Placenta and Umbilical Cord Summary PDF

‫”قالوا سبحانك ال علم لنا إال ما علمتنا إنك أنت‬ ‫العليم الحكيم“ سورة البقرة آية (‪)32‬‬  By: Dr. Elsayed Aly Metwally Professor of Anatomy & Embryology Master Degree in tropical medicine - Nutrition Diploma Faculty of Medicine - Alexandria University...

‫”قالوا سبحانك ال علم لنا إال ما علمتنا إنك أنت‬ ‫العليم الحكيم“ سورة البقرة آية (‪)32‬‬  By: Dr. Elsayed Aly Metwally Professor of Anatomy & Embryology Master Degree in tropical medicine - Nutrition Diploma Faculty of Medicine - Alexandria University Fate of body stalk  Forms Wharton's jelly(mucoid connective) Fate of yolk stalk  It connects the mid gut and the extra embryonic yolk sac.  It degenerates.  Vitelline blood vessels which form superior mesenteric artery Fate of allantois  Small diverticulum attached to the hind gut.  It transfers into urachus and later on to median umbilical ligament.  The primary mesoderm around it forms umbilical blood vessels. Definitive umbilical cord  Covering made of amniotic membrane  Vessels: Two umbilical arteries and One umbilical vein  Mucoid connective tissue (Wharton’s jelly)  2 remnants: yolk stalk and extraembryoic celom  (Covering+vessels+Whartons jelly+2 remnants)  The two umbilical arteries & single umbilical vein are responsible for the nutrition of the embryo.  The vein carries oxygen to the embryo, while the arteries carry CO2 & waste product of the embryo to the mother.  1- Umbilical arteries forms the medial umbilical ligaments.  2- Umbilical vein forms ligamentum teres of the liver.  The right vein degenenerates early. Left ----- ligamentum teres  3- allantois forms the median umbilical ligament.  4- Yolk stalk disappears.  5- Extra-embryonic coelom disappears.  6- Vitelline arteries forms superior mesenteric artery. 1. PP parietalis: The placenta lies away from the internal os of the cervical canal. 2. PP marginalis: The placenta covers partially the internal os. During labour, it is shifted upwards away from the internal os. 3. PP centralis: the placenta completely covers the internal os. During labour, it leads to ante-partum Hge. It may lead to malposition of foetus.