Placenta Quiz

When does the embryo invade the endometrium? Day 7 What does hCG stand for? Human chorionic gonadotropin Where is is secreted from? Trophectoderm When is hCG first detectable? Day 8

What are the THREE aims of the implantation? (in terms of placenta..) Anchor the placenta Establishment of basic unit of exchange between fetus and mother Establishment of blood flow within the placenta

What is the function of hCG? Maintains the corpus lutem Why is this required? Corpus luteum produced progesterone. Progesterone maintains the endometrium until the placenta can take over. What are the three stages/classifications of the villus? Primary  syncytio trophoblast penetrated by cords of cytotrophoblast Secondary  penetrated by mesenchymal cells Tertiary  penetrated by fetal vessels

How does the villus further develop to adapt to the increasing need of the developing foetus? Thinning of placental barrier Margination of foetal vessels Massive expansion of surface area by arborisation What is the consequence when the placenta is not meeting the needs of the foetus? IUGR  intra-uterine growth restriction

The umbilical cord .. 1. Is made up of 2 umbilical veins and 1 umbilical artery? OR .. 2. Is made up of 2 umbilical arteries and 1 umbilical vein? The second one is correct (think AVA) – which carries oxygenated blood? The umbilical vein carries oxygenated blood from mum What’s the name of the other component of the umbilical cord? Wharton’s jelly

List THREE factors that affect maternalfetal bloodflow Fetal heart/vessels Umbilical vessels Uteroplacental flow – mum MCQ: Maternal-fetal blood flow is which of the following? High pressure, high flow Low pressure, low flow High pressure, low flow Low pressure, high flow

Now for some labeling .. Of a mature placenta Umbilical cord Amnion 4. Amniotic membrane 7. Endometrial arteries 8. Endometrial veins 11. Myometrium 12. Decidual basalis WORDS: chorionic villi, placental septa, umbilical cord, amniotic membrane, smooth chorion, umbilical vessels, decidua basalis, endometrial arteries and veins, cytotrophoblastic shell, stump of main villus stem, main villus stem, myometrium, and amniotic fluid. For today just name 1. 2. 4. 7. 8. 11. please.

What are the THREE placental functions? Endocrine – steroid and peptide hormones Transfer – of nutrition, waste and gas exchange Immunity What are the TWO peptide hormones? Human chorionic gonadotropin Human placental lactogen Which one of these two peaks at 10-12 weeks? hCG What is the role of human placental lactogen? Glucose metabolism during pregnancy  make mum resistant to insulin. Reduced uptake of glucose into maternal cells to favour fetal supply. What are the TWO steroid hormones? Oestrogen Progesterone

Match the molecule with the transfer mechanism! Water Amino acids Glucose Immunoglobulins Iron Alcohol Active transport Pinocytosis Simple diffusion Facilitated diffusion Which immunoglobulin crosses the placenta? IgG  think the placenta is gross Which immunoglobulin is found in breast milk? IgA  breast milk, areolar

List FOUR placenta dysfunctions Position/development Growth Blood flow compromised Transport of “bad stuff” eg. Alcohol What does “placenta praevia” mean? Low-lying placenta  example of a positional dysfunction What are the three types? Marginal Complete Low-lying

Matching up placenta problems Matching up placenta problems .. What is placenta accreta, increta, percreta? Uncontrolled invasion or abnormal attachment of the placenta to the myometrium. Placenta increta Placenta accreta Placenta percreta Placenta villi invade into part of myometrium Placenta villi invade into whole myometrium Placenta villi invade though the full thickness of the myometrium to the serosa layer and may cause uterine rupture.

How can placental abruption present in a pregnant lady? Per vaginal bleeding What are the THREE types? Revealed Concealed Concealed and revealed

List THREE growth dysfunctions of the placenta Uncontrolled growth Gestational trophoblastic disease Molar/choriocarcinoma List THREE blood flow dysfunctions of the placenta Inadequate placentation  pre-eclampsia Mechanical  IVC compression Volume  maternal haemorrhage, can lead to fetal growth restriction

Pre-eclampsia  definition Failure of normal invasion of trophoblast cells which leads to less adapted maternal spiral arteries in the placenta  this is an example of abnormal placental development. Triad of clinical features? Hypertension Proteinuria Oedema What is eclampsia? Tonic-clonic seizures in pregnancy

What are FOUR causes of placental dysfunction? Smoking Drugs eg. Cocaine Alcohol – by what transport mechanism does this reach the fetus? What can this cause in the fetus? Simple diffusion – moves down the concentration gradient to the fetus causing fetal alcohol syndrome. 4. Infectious agents eg. Rubella, hepatitis B/C, HIV Fetal alcohol syndrome causes defects in the heart, neurological in terms of behaviour and development and midline facial abnormalities like the lack of philtrum (cupids bow I think) and flattened nose

Thank-you! Any questions? Good luck with your revision 