Common Pathologies of Pregnancy Flashcards
What does it mean when progesterone levels continue to rise rather than fall after the peak?
Egg has been fertilised
What does progesterone do to the lining of the endometrium?
Turns endometrium into decidua
What is decidua?
The thick layer of modified mucous membrane which lines the uterus during pregnancy and is shed with the afterbirth
What is the effect of turning endometrium into decidua?
Increases vascularity
Between glands and vessels, the stromal cells enlarge and become procoagulant => stops bleeding
What is a fertilised egg?
Chorion
What surrounds the outer edge of the chorion?
Trophoblast cells
Which hormone is produced by trophoblast cells?
Beta-human Chorionic Gonadotrophin (B-hCG)
What is the target for B-hCG?
Corpus luteum in the ovary
What is the function of B-hCG?
To stimulate corpus luteum to produce progestogen, which stops decidua from shedding
What is B-hCG used for clincially?
Forms basis of pregnancy tests
What is an ectopic pregnancy?
Pregnancy in the wrong anatomical site
Most common in fallopian tube
Lack of proper decidual layer and small size of tube predispose to haemorrhage and rupture
If it presents early woman may not even know she is pregnant
What is molar pregnancy?
A form of precancer of trophoblast cells
What is a common cause of molar pregnancy?
2 sperm fertilising one egg with no chromosomes
What is a choriocarcinoma?
Molar pregnaces can be a form of precancer of trophoblast cells which can give rise to a malignant tumour
How is a molar pregnancy treated if BhCG returns to normal?
No further treatment
How is a molar pregnancy treated if BhCG does not return to normal?
Cure by methotrexate
What is the effect of the mother’s methylation of the genes in the ovary?
Promotion of early baby growth
What is the effect of the father’s methylation of the genes in the testis?
Promotion of placenta growth via trophoblast proliferation
What happens when 2 sperm fertilise one egg with no chromosomes?
Molar pregnancy due to imbalance in methylated genes - trophoblast cells proliferate because they have too many of the father’s methylated genes => overgrowth of placenta/no foetal growth
How does diabetes in the pregnant mother affect the foetus?
Larger baby due to longterm hyperinsulinaemia and hyperglycaemia
Problems associated with diabetes in pregnancy
Malformations
Huge babies that obstruct labour
Intrauterine death
Neonatal hypoglycaemia
What is chorioamnionitis?
Neutrophils present in membranes
Do opiates cross the placenta?
Yes
Why would a woman with an IV heroin addiction be prebooked into a large maternity unit beside the neonatal unit?
So that baby can be admitted to neonatal unit and treated for heroin withdrawal
Why would the baby of a woman with an IV heroin addiction ‘overfeed’ with constant mouthing movements at 3 weeks?
Methodone withdrawal (takes longer to get out of the system)
What is a common cause of intrauterine death and neonatal illness?
Overtwisted cord
What is abruption?
Separation of placenta from uterine wall
Results in hypoxia in baby
Often causes antepartum haemorrhage in mother
Causes of abruption
Hypertension
Trauma
Other (eg cocaine)
