1. Fetal membranes, umbilical cord and placenta Dr. Sanjaya Adikari Department of Anatomy

2. Objectives Describe the structure and function of the placenta, umbilical cord and membranes

4. 1 23 45

6. Chorionic plate Decidual plate

7. Chorionic villi Lacunar/intervillous spaces Cotyledon (15-20)

8. Macroscopic appearance of placenta

9. Placenta – fetal surface

10. Placenta – maternal surface

11. Placenta and membranes

12. What is placental barrier?

13. 2 1 Placental barrier

14. Blastocyst

15. Functions of the placenta Exchange of gases Removal of metabolic products Nutrition Transmission of maternal Ab Production of hormones

16. Placental hormones Human chorionic gonadotropin-hCG Progesterone Oestrogens Human chorionic somatomammotropin-hCS Relaxin These are secreted into the maternal circulation. Most maternal hormones do not cross the placenta.

17. 20103040Weeks hCG 612 Maintains the corpus luteum during the initial period of pregnancy Progesterone Oestriol Maintains the pregnancy Relaxin Inhibits myometrial contractions hCS Lactogenic function Growth stimulation

18. 20103040Weeks hCG 612 Progesterone Oestriol Relaxin hCS

19. Unwanted functions of placenta Transfer of infectious agents Transfer of drugs

20. Functions of the fetal membranes Protection/shock absorption

21. Umbilical cord umbilical arteries umbilical vein Wharton’s jelly

23. References Review of medical physiology by William F. Ganong Medical embryology by Jan Langman http://www.answers.com/topic/umbilical-cord