Pathologies of Pregnancy Flashcards
1
Q
When do the hormones peak in a normal cycle
A
- Day 0-14 - oestrogen peaks
- Day 14-28 - Progesterone peaks
2
Q
What does progesterone do
A
- Thickens the lining of the endometrium
- Changes cells in the endometrium
- Turn endometria into decidua
- Increases vascularity
- Between glands and vessels the stromal cells enlarge and become procoagulant –> stops bleeding
3
Q
What is another name for the egg
A
- Chorion
4
Q
What surrounds the outer edge of the chorion
A
- Trophoblast cells (placental cells) on teh oustide
- Produce beta-human chorionic gonadotrophin (B-hCG)
5
Q
What happens once the egg is fertilised
A
- Fertilised egg burrows into decidua
- Trophoblast cells stream off to invade mothers blood vessels and eventually link them to the foetus
- Eventually the chorionic villi, covered by trophoblast cells, are bathed in the mothers blood, forming forerunner of placenta)
- Decidual stroma cells are procoagulant and stop trophoblast cells causing too much bleeding
6
Q
What is B-hCG
A
- Target is corpus luteum in ovary
- Function is to stimulate corpus luteum to produce progetserone, which stops decidua from shedding
- Forms basis of pregnancy tests
- Stimulates the ovary to produce progesterone throughout pregnancy, preventing the decidua from shedding
7
Q
What is an ectopic pregnancy
A
- Pregnancy in the wrong anatomica site
- If early, woman may not even know she is pregnant
8
Q
What occurs in an ectopic pregnancy
A
- Lack of proper decidual layer and small size of tube predispose to haemorrhage and ruputre
9
Q
Where is the most common location for ectopic pregnancy
A
- fallopian tube
10
Q
What occurs in a normal ovary
A
- Mother switches off certain genes in ova (eggs) by methylating them
- Father switches off different genes in sperm by methylating them
11
Q
How do gene changes growth in pregnancy
A
- Mothers changes promote early baby growth
- Fathers changes promote early placenta growth via trophoblast proliferation
12
Q
What are the causes of a molar pregnancy
A
- Most often caused by 2 sperm fertilising with 1 egg and no chromosomes
13
Q
What does a molar pregnancy result in
A
- Imbalance in methylated (switched off) genes
- Resulting in trophoblast overgrowth –> overgrowth of placenta
14
Q
What are the groups of trophoblast cells
A
- A form of pre-cancer
- If it persists can give rise to malignant tumour - choriocarcinoma
15
Q
Treatment of molar pregnancy
A
- If B-hCG return to normal - no further treatment
- If B-hCG stays high (persistent disease) cure by methotrexate
