Reproductive pathophysiology

Question 1

WHO preterm definition

Answer 1

before 37 weeks

Question 2

Why are lungs an issue?

Answer 2

Lack of surfactant

Question 3

Layers of the pregnant uterus

Answer 3

Amnion, chorion, decidua, myometrium

Question 4

Infections associated with preterm birth?

Answer 4

Gram positive (ureaplasma parvum, ureaplasma urealyticum, strep), salmonella typhirium, Gardenerella vaginalis (bac. vaginosis). Tox plasmosis and malaria in developing countries. Can have two hit mechanism with initial candida/adenovirus initial infection

Question 5

How do infections stimulate labour?

Answer 5

Inflammatory pathways enable return to pre-preg. state, but bacterial LPS activate TLR4, stimulate IL-6/TNF alpha (via NFkB) - pro inflammatory) as well as IL-1beta

Question 6

Fetal fibronectin

Answer 6

produced in decidua, reaches upper cervix. Possible indiciator of pre-term labour/short cervix

Question 7

Tocolysis

Answer 7

medical therapy to delay labour. Includes CCBs (L type), atosiban (oxytocin receptor antagonist), COX-2 inhib (inhibi prostg), NO donors (promote relaxation). None beneficial to fetus, just give some time
No proved benefit to Abx or other channel modulators

Question 8

Prevention

Answer 8

Progesterone admin, cervical clercage

Question 9

Pre-eclampsia

Answer 9

Dx criteria are HT+proteinuria (or underlying renal dysfunction). Early onset is <34, late is >34 weeks. Eatrly onset is worse.
Other symptoms are oedema, epigastric pain, thrombocytopoenia, cerebral/visual disturvance, headache, sudden weight gain, muscle twitch, pulmonary oedema. May have raisedliver enzymes.

Question 10

Pathophysiology of pre-eclampsia

Answer 10

In pergnancy, should be very little resistance to flow to placenta. Dysfunction thought to be due to trophoblast debris entering maternal circ. Poor trophoblast invasion, poor vasodilatory response, endothelial dysfunction (arteries don’t dilate fully, endothelial damage). Ros and peroxides also implicated.

Question 11

Pre-eclampsia risk factors

Answer 11

New partner, family Hx, maternal age (either extreme), CVD, renal disease, obesity

Question 12

Pre-eclampsia treatment

Answer 12

low dose aspirin. Magnesium sulphate given for severe pre-eclampsia. Only real treatment is delivery of placenta (and baby).
Preeclamptic mothers and offspring have increased stroke risk

Question 13

Intrauterine growth restriction

Answer 13

below 10th centile. Need serial growth measurements.Shares pre-eclampsia aetiology.

Question 14

Asymmetrical IUGR

Answer 14

Typically late onset. Brain spared at expense of other organs. Examples are chronic hypoxia, malnutrition

Question 15

Symmetrical IUGR

Answer 15

LEss common than asymmetrical. Typically early onset (<32 weeks). Normal ponderal index (HC/AC, both perameters reduced). Can be genetic disorders, drug use, or TORCH (toxoplasmosis, rubella, CMV)

Question 16

Fetal undernutrition sequalae

Answer 16

Increases cortisol, pancreas/liver/kidneys/blood vessels underdeveloped, predisposes to insulin resistance, central obesity and HT/hyperlilidaemia. Increased risk of T2D

Question 17

Dystocia

Answer 17

Responsible for 50% of C sections.
uncoordinated uterine contractions lead to abnormal fetal presentation (head hasn’t turned), but can also be cephalopelvic disproportion (head:pelvis ratio). Oxytocin and Pgs may help

Question 18

Shoulder dystocia

Answer 18

Different from dystocia. More common in larger babies, and with diabetes/maternal obesity

Question 19

Gestational diabetes

Answer 19

new onset of glucose intolerance in pregnancy. Tends to produce macrosomia (large baby). Increased T2D risk

Question 20

Zika

Answer 20

Viral, causes microcephaly. Transmission via mosquito/sexual/blood/semen, placenta.
Symptoms - rash, myalgia, arthalgia, fever. Dx by PCR Causes developmental delay in babies.

Question 21

Gestational HT

Answer 21

new onset HT after 20weeks pregnancy without pre-eclampsia features

Question 22

superimposed pre-eclampsia

Answer 22

pre-eclampsia in women with chronic HT/renal disease

Question 23

Key feature of pre-eclampsia

Answer 23

proteinuria. Heavily associated with IUGR

Question 24

Role of Angiotensin 2 in pre-eclampsia

Answer 24

In pregnancy, sensitivity to AG2 is lost (angiotensin 2 counters local vasodilator PGs). Pre-ecmaptic women retain AG2 sensitivity

Question 25

HELLP syndrome

Answer 25

Haemolysis, elevated liver enzymes, low platelet count. Sx are headache, blurred vision, band pain (liver), nausea/vomiting and parasthesia. DDx of gall bladder, pyelonephritis, peptic ulcer, gastroenteritis, fatty liver of prenancy, hepatitis. Resulting thrombocytopoaenia can cause liver/brain haemorrhage.

Question 26

HT control in pregnancy

Answer 26

Methyldopa (alpha 2 antagonist), hydralazine , labetalol(mixed alpha/beta adrenoceptor antagonist - CI asthma), prazosin, nifedipine (CCB)

ACEi, ARB, diuretics and atenolol are CI

Question 27

What can be given to avoid resp distress syndrome

Answer 27

betamethasone

Question 28

placenta praevia

Answer 28

placenta is too close to cervix, can be partial or total. C section required

Question 29

Placenta accreta/percreta

Answer 29

placenta grows too deep and attaches to myometrium. Risk of heavy bleeding at birth. Accreta is partial thickness, percreta is full thickness and may need hysterectomy

Question 30

placental abruption

Answer 30

3rd trimester. lining separates from uterus - placental insufficiency