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Flashcards in preterm birth Deck (22):
1

what is preterm labour

term = labour before <37 weeks

very preterm = <32 weeks

prematurity is an abnormality - it is a failure of uterine quiescence
- a failure of the uterus to keep the baby in until the right time
(more than just dates)

2

cost of preterm birth

- neonatal complications
- long term health problems
- individual and family cost
- societal cost
- neonatal enchephalopathy
- handicup potential e.g. cerebral palsy, sight, hearing, resp, behaviour

3

causes of preterm

- endocrine maturation 'stress'

- intrauterine haemorrhage

- intrauterine infection

- intrauterine stretch
-membrane disruption
-myometrial distention

(flowchart in book)

4

failure of quiescence

functional levels of P4 and interaction with receptors is disturbed and uterus goes into labour
- inflammation is the most potent cause

5

preterm activation problems

- uterine stretch-growth
- fetal HPA axis (stress)
- up-regulation of myometrium
- problems in cervix

6

function of cervix

physical barrier against baby

barrier for ascending organisms

7

cervical ripening

-active process
-inflammation like process
-infiltration of leukocytes
-increase in cytokines
-increase in MMPs
-independent of uterine activity

8

what are triggers to upset peace

- infection
- stretch
membrane disruption
myometrial distension
- tissue damage esp cervix
- placentation
growth of fetus
hormone-P4
PG release
poor attachment-bleeding

9

release of PG

- final common pathway in activation phase

phospholipases release arachidonic acid from cell membranes

10

causes of PG release

- increase myometrial contractility

- lead to cervix changes

- associated with membrane rupture

11

problems of preterm birth

- immature fetus
- often malpresentation e.g. breech
- often maternal comorbidities
- often have complicated C sections
- risks of recurrence
- may have poor outcomes

12

limits of survival

lung development
- inability to undertake gas exchange

13

who is at risk of prematurity

- previous history of PTB
- smoking
- multiple pregnancy e.g. twins
- maternal age
- obstetric history
- no prenatal care
- short cervical lengths

14

fetal fibronectin

biomarker

- protein that sits between chorion and decidua
- high in early pregnancy and late pregnancy

measure it and if its high when it shouldn't be you know something is wrong

15

treatment given to abnormal pathological activation (with preterm labour)

tocolysis

steroids

MagSO4

16

tocolysis

supresses preterm labour

Ca2+ channel blocker e.g. nifedipine

17

steriods

antenatal corticosteroids

- prevents death from respiratory distress and reduce premature bleeding in the brain and infection in gut wall

e.g. betamethasone

18

magnesium sulphate

if baby is under 30 weeks can give IV infusion to mother

- reduces risk of cerebral palsy

19

prevention strategies

- reduce smoking

- cervical cerclage
- drug therapies
- preterm birth clinics

20

options - strategies

risk assessment and action
- social, smoking, prior PTB

P4

Cervix length measured

Ca2+ for preeclampsia

21

progesterone therapy

- doesnt work for everyone or twins
- efficacious in prior spontaneous PTB
- efficacious in short Cx
- not effective if Cx <10mm
- role of P4 some benefits
- injection may be unsafe or ineffective
- not effective when women is contracting

22

improving outcomes

-risk selection-history taking
-stop smoking
-assess maternal health risks for early delivery
- in patients at risk asess Cx length (use P4 for short)

use steriods and MagSO4 if delivery likely