Preterm Labour Flashcards
Define PROM
Chorio-amniotic membrane rupture before onset of labour
Premature rupture
Diagnosis PROM? (5)
- Maternal history + sterile speculum: pool of fluid in vagina - amiorrhexis
- microscopic examination of vaginal fluid: characteristic ferning pattern
- nitrazine test: ph of vaginal fluid (Amniotic range 7 - 7,3)
- amniosure / aminiosense ( panty liner that changes colour at ph > 5); dipstix; litmus paper
- ultrasound: oligohydramnios to help confirm diagnosis
Management PROM? (10)
- Admit
- maternal surveillance for signs chorio amnionitis
- foetal surveillance with daily ctg
- antibiotics
→ erythromycin 500 mg 6 hourly po for 10 days or
→ ampicillin 2g qid for 48 hours + then amoxicillin 500 mg po TDS 5 days + azithromycin 500mg daily po 3 days.
→ add metronidazole 400 mg TDS po for 5 days if going for c/s
→ treatment cervical chorio amnionitis : deliver + ampicillin 2 g bid iv + gentamycin 240 mg daily iv - inhibit uterine contractions (tocolysis)
- glucoconticosteroids: only use for 24 hours with concurrent administration antibiotics and corticosteroids and absence of chorio amnionitis
- mgso4 24 - 32 weeks + imminent delivery
- amnionfusion for prolonging Latency: 250 ml isotonic normal saline associated with increase in latency from 9-21 days
- timing of delivery: consider from 34 weeks
Define preterm labour
Uterine contractions > 4/20 mins and cervical changes with intact membranes
< 37 weeks
Define term pregnancy
37.0 weeks - 41.6 weeks
Define early term pregnancy
37.0 weeks- 38.6 weeks (higher neonatal MM. )
Name 4 risk factors preterm labour
- Prior preterm birth
- cervical length < 25 mm before 24 weeks gestation
- history cervical surgery: conisation, lletz
- behavioural: low maternal pre-pregnancy weight, smoking
Primary Prevention preterm labour? (6)
Primary: all women - screening
- single cervical length assessment between 18 - 22 weeks
- screen and treat asymptomatic bacteruria if urine colony count > 10^5
- decrease rate multiple gestation from assisted reproduction
- smoking cessation
- reduce Occupational fatigue: avoid work > 42 hours week or stand > 6 hours/ day
- avoid short inter-pregnancy interval: < 6 months high risk
- screen for HIV, ANC, educate, avoid extremes of age
Secondary prevention preterm labour? (5)
Secondary: women with risk factors
- if previous preterm: regular cervical length screening after 16 weeks
- progesterone: cervical length <25 mm
- cervical circlage: history preterm and short cervix, or elective if 3 or more second trimester miscarriage
- trans abdominal circlage: previous failed cervical circlage, inability to perform cervical circlage
- twin gestation: vaginal progesterone. No benefit cerclage or pessary
Tertiary prevention preterm labour?
Initiated after parturition (giving birth) with goal of improving outcomes for infants
Approach to preterm labour? (5)
- Sterile speculum to rule out ROM
- consider uterine culture
- continuous ctg
Determine If 3cm dilated or cervical change
< 3cm dilated or no cervical change
Which gestational age and foetal weight is considered to have lower risk perinatal mortality, and can be delivered if necessary?
> 34 weeks
2 kg
Management preterm labour with 3cm dilated or cervical change? (7)
- Corticosteroids
- Consult NICU
- establish foetal presentation, EFW, AFI ( amniotic fluid index), placental location
- consider amniocentesis to rule out infection; consider antibiotics (GBS)
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Tocolyse - 26 weeks - 31.6 weeks
→ indomethacin 50 - 100 mg load , then 25 -50 mg 6 hourly x 24 h
→ consider mgso4 if delivery imminent in 24 hours - 32 - 33.6 weeks
→ nifedipine 10 mg po every 15 min X4. Continue 10-20 mg 6 hourly x 24 h. Bp > 90/50
Management preterm labour with < 3cm dilated or no cervical change? (4)
Perform TVS CL (cervical length )
- <20 mm → suggest admission, steroids, tocolyse. Consider amniocentesis to rule out infection
- 20 - 29 mm
→ if contractions persist, observe and consider repeat TVS CL
> persistent contractions with cervical change → follow protocol + tocolyse
> stable: discharge home - > 30 mm → discharge
Dose indomethacin for tocolysis?
Load 50 - 100 mg
Then
25 - 50 mg 6 hourly
X 24 hours
