By Joshua Bower Peer Support 2013/2014

Placenta –Understand how the placenta forms and grows –Know how the structure of the placenta is linked to its functions –Know in principle the main functions of the placenta –Know in principle some of the main problems related to placental dysfunction Pre-eclampsia –Relate maternal adaptations in pregnancy to some common complications of pregnancy including pre-eclampsia and gestational diabetes Learning Outcomes

TRUE or FALSE? The embryo implants into the uterine endometrium around day 7.

Anchor the placenta Establish the chorionic villus Establish maternal/foetal blood flow within the placenta What are the THREE aims of implantation? [3]

Thinning of placental barrier Margination of foetal vessels Massive expansion of surface area by arborisation How does the chorionic villus adapt to meet the expanding need of the developing foetus? [3]

TRUE or FALSE? There are 2 umbilical veins and 1 umbilical artery.

TRUE or FALSE? Maternal-foetal blood flow is low pressure with a low flow rate.

Endocrine (produce steroid and peptide hormones) Transfer (nutrition, waste, gas exchange) Immunity What are the THREE functions of the placenta? [3]

Which of the following is measured in a pregnancy test? FSH LH Oestradiol hPL hCG Testosterone

TRUE or FALSE? hCG and hPL are peptide hormones

(i) weeks (ii) Levels rise steadily during pregnancy When do (i) hCG and (ii) hPL levels peak?

hCG maintains the corpus luteum The corpus luteum produces progesterone, which maintains a viable endometrium, until the placenta takes over What is the function of hCG, and why is this important?

H2O Glucose Immunoglobulins Amino acids Alcohol Passive diffusion Receptor-mediated pinocytosis Passive diffusion Facilitated diffusion Active transport Which molecule uses each transfer mechanism?

TRUE or FALSE? IgM can cross the placental barrier

What effect does hCG have on maternal IgA, IgG and IgM? Why? Humoral immune depression to prevent rejection of the placenta by the mum, and vice versa Makes mother more susceptible to viruses

What term is used to denote a low-lying placenta?

A pregnant woman of 8 months presents with significant PV bleeding. What may have happened?

Uncontrolled invasion of the placenta … Accreta – …into part of myometrium Increta – …into whole myometrium Percreta – …beyond myometrium into uterine serosa, and thus can atttach to the bladder or rectum What is placenta accreta, increta and percreta?

Failure of the placenta and uterus to separate The placenta maintains uterine blood supply, causing PV bleeding Treatment – “extraction” of the placental tissue What is post-partum haemorrhage, and what is the treatment?

Choriocarcinoma What is a malignant gestational trophoblastic tumour called?

Hydatidiform mole –Where a non-viable egg implants in the uterus –It is a gestational trophoblastic disease What is another name for a molar pregnancy?

Hydatidiform moles usually have high levels of hCG In ectopic pregnancies, hCG levels are low How can you differentiate a hydatidiform mole from an ectopic pregnancy?

Intra-uterine growth restriction (IUGR) What term describes when the placenta compensation cannot meet the needs of the foetus?

A pregnant lady presents to A+E with swollen hands and face. Examination reveals she is hypertensive with proteinuria. Diagnosis? Pre-eclampsia Oedema Proteinuria Hypertension

Caused by abnormal placentation (development and arrangement of the placenta) or abnormal placental function Proposed mechanism: Reduced uterine-placental blood flow results in placental ischaemia, leading to release of factors causing endothelial dysfunction (e.g. TNF-alpha, IL-6), reduced NO and increased ROS This in turn leads to altered renal function, increased TPR and ultimately hypertension What is pre-eclampsia?

Acute and life-threatening tonic-clonic seizures in pregnancy What is eclampsia?

* Won’t be examined** ** …probably