Common Pathologies of Pregnancy

Question 1

What does progesterone do to the endometrium when an egg if fertilised?

Answer 1

• thickens endometrium
• turns endometrium to decidua
• inc. vascularity
• stromal cells enlarge + become procoagulant

Question 2

What are trophoblast cells and what do they produce?

Answer 2

• cells on outside of fertilised egg (chorion)
• Beta-human Chorionic Gonadotrophin (B-hCG)

Question 3

What is the target and function for Beta-human Chorionic Gonadotrophin (B-hCG)?

Answer 3

• target is corpus luteum in ovary
• stimulates corpus luteum to produce progesterone- prevents shedding of decidua

Question 4

How is Beta-human Chorionic Gonadotrophin (B-hCG) used clinically?

Answer 4

• forms basis of pregnancy tests

Question 5

What happens once the fertilised egg burrows into the decidua?

Answer 5

• trophoblast cells stream off into maternal blood vessels
• eventually linking maternal and fetal blood vessels
• chorionic villi covered in trophoblasts move into the decidua
• eventually are bathed in maternal blood and form forerunner of placenta

Question 6

What is an ectopic pregnancy?

Answer 6

• pregnancy in wrong anatomical site
• most common in fallopian tube
• lack of desidual layer + small tube- predisposes to haemorrhage and rupture

Question 7

What is a molar pregnancy?

Answer 7

• fertilised egg has large chorionic villi with overgrowth of trophoblast cells
• can be caused by 2 sperm fertilising 1 egg that has no chromosomes
• causes imbalance in methylated (switched off) genes
• causes overgrowth of placenta and no fetal growth
• a precancer of trophoblast cells
• rarely leads to malignant tumour- choriocarcinoma

Question 8

What is the treatment for a molar pregnancy?

Answer 8

• if B-hCG returns to normal- nor further treatment
• if b-hCG stays high- methotrexate

Question 9

Why does poorly controlled diabetes during pregnancy result in a large baby?

Answer 9

• glucose crosses placenta
• baby inc. insulin
• baby cannot reduce its own glucose levels if mother keeps sending glucose across placenta
• longterm high insulin + high glucose -> massive growth

Question 10

What other problems can poorly controlled diabetes in pregnancy create?

Answer 10

• malformations
• huge babies that obstruct labour
• intrauterine death (IUD)- metabolic and hypoxic probblems
• neonatal hypoglycaemia

* good diabetic control is required before conception (prevent malformations) and throughout pregnancy (prevent metabolic complications)

Question 11

What is acute chorioamnionitis + ascending infection?

Answer 11

• acute inflammation- neutrophils present in membranes, cord and fetal plate of placenta
• bacteria which are typically perineal or perianal ascend vagina and get into amniotic sac, causing acute chorioamnionitis

Question 12

What is the presentation of ascending infection in mother and baby?

Answer 12

• mother- well OR fever and raised neutrophils in blood
• baby- intrauterine death, ill 1st day of life then neonatal unit, cerebral palsy later on in life

Question 13

How does ascending infection affect baby’s brain?

Answer 13

• neutrophils produce cytokine ‘storm’
• activates some brain cells, whcih get damaged by normal hypoxia of labour

Question 14

Opiates cross the placenta, how do they affect pregnancy?

Answer 14

• normal pregnancy if mother eats well
• baby must be treated at neonatal unit for heroin withdrawl, after birth
• later withdraw from methadone

Question 15

What is a common cause of intrauterine death and neonatal illness?

Answer 15

Overtwisted cord

Question 16

What is a placental abruption