Lecture 14: Parturition - Preterm birth Flashcards

1
Q

What is ‘pre-term labour’

A

Preterm: Labour before 37 weeks gestation (9%)

Very Preterm: Very preterm (~2%)

More then just dates, preterm is an abnormality: a failure of the uterine quiscence (a failure of the uterus to keep the baby in until the right time)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which factors determine survival for a preterm baby?

A

Gestation and birth weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Outcomes are good for a preterm baby at ___ weeks and ___g

A

28-29 weeks 1250 g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are four factors that might cause premature birth?

A
  • Stress - Bleeding - Infection - XS stretch
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The earlier the labour occurs the more likely it is to have an ____ aetiology

A

Infectious/inflammatory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why might cervical damage lead to preterm labour?

A

Weakens the bacteriostatic barrier (operculum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Health problems of preterm birth?

A
  • Immature fetus so often unwell
  • Malpresentation: breech (butt 1st)
  • Maternal co-morbidities
  • complicated caesarean sections
  • Risk of recurrence
  • Poor health outcomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Lung development determines _________

A

Limit of viability, determined by the fetal organ of gas exchange, the placenta.

If the type II cells in our lungs can’t effectively produce surfactant, which coats alveoli and reduces surface tension, and babies would require huge amount of energy to overcome this and expand lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two main causes of iatrogenic preterm birth?

A
  • Maternal disease (preeclampsia) - Foetal health (IUGR)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is eclampsia?

A

A grand-mal convulsion due to endovascular inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the highest risk factor for PTB?

A

Previous PTB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are non-modifiable risk factors for PTB?

A
  • Maternal age - Obstetric history - SES - Race
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are modifiable risk factors for PTB?

A
  • Smoking - Need for cervical surgery - Reproductive technologies - No prenatal care
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What other markers have been suggested for PTB risk screening?

A
  • Serum biomarkers - Cervicovaginal fluids - Cervical length - Uterine activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Foetal fibronectin is a biologial glue that sits between the ___ and ___

A

Decidua and chorion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

After __ weeks pregnancy there is not supposed to be any fibronectin in the vagina

A

20

17
Q

After __ weeks pregnancy there is not supposed to be any fibronectin in the vagina

A

20

18
Q

Foetal fibronectin is a biologial glue that sits between the ___ and ___

A

Decidua and chorion

19
Q

What other markers have been suggested for PTB risk screening?

A
  • Serum biomarkers - Cervicovaginal fluids - Cervical length - Uterine activity
20
Q

What are modifiable risk factors for PTB?

A
  • Smoking - Need for cervical surgery - Reproductive technologies - No prenatal care
21
Q

What are non-modifiable risk factors for PTB?

A
  • Maternal age - Obstetric history - SES - Race
22
Q

What is the highest risk factor for PTB?

A

Previous PTB

23
Q

What is eclampsia?

A

A grand-mal convulsion due to endovascular inflammation

24
Q

What are the two main causes of iatrogenic preterm birth?

A
  • Maternal disease (preeclampsia) - Foetal health (IUGR)
25
Q

How do we measure Fetal fibronectin in threatened PTL

A
  • If positive: 30% deliver in 7-10 days
  • Negative: 99.5% don’t deliver in 7-10days (what you want)

Used to decide who to transfer and who to treat with steroids

Checks if decidual lining is intact!

26
Q

Intervention to suppress PTL: Tocolysis

A

Drugs: various modes of action, but the main ones are

  • Ca2+ channel blockers** (Nifedipine)
  • Oxytocin receptor blocker (atosiban $$$)

Used to be B2 agonist salbutammol, PG antagonists

27
Q

Which antenatal corticosteroid is used to prevent respiratory distress syndrome?

A

Betamethasone

28
Q

Which drug is administered to premature babies for neuroprotection?

A

MgSO4

29
Q

MgSO4 is administered in babies under __ weeks ~ ___h before birth

A

30 weeks 6h before birth

30
Q

When is progesterone gel most effective in suppressing labour?

A
  • Cx length 10-20mm - 19-23 wks - Singletons - Prior STB
31
Q

What are two effective interventions to prevent PTB in women with a short cervix?

A

Progesterone and cervical cerclage

32
Q

Which antenatal corticosteroid is used to prevent respiratory distress syndrome?

A

Betamethasone

33
Q

Which drug is administered to premature babies for neuroprotection?

A

MgSO4

34
Q

MgSO4 is administered in babies under __ weeks ~ ___h before birth

A

30 weeks 6h before birth

35
Q

When is progesterone gel most effective in suppressing labour?

A
  • Cx length 10-20mm - 19-23 wks - Singletons - Prior STB
36
Q

What are two effective interventions to prevent PTB in women with a short cervix?

A

Progesterone and cervical cerclage