Spontaneous preterm birth prevention in multiple pregnancy

M R C O G PA R T 2 · S O S P O C K E T C A R D · K N O W L E D G E A R E A 5 – A N T E N ATA L C A R E

Spontaneous Preterm Birth Prevention in Multiple Pregnancy Murray SR et al. Spontaneous preterm birth prevention in multiple pregnancy. TOG 2018;20:57–63. doi:10.1111/tog.12460

3× 50% <30 mm PERINATAL MORTALITY, TWINS VS SINGLETONS TWINS DELIVERING <37 WEEKS (SCOTLAND) CERVICAL LENGTH @18WKS MOST PREDICTIVE OF ≤28WK BIRTH

DO N' T-M IS S FA C TS

1. Twins: 3× perinatal mortality vs singletons; 50% deliver <37 weeks, ~20% <34 weeks (Scotland)

2. CL <30 mm at 18 weeks most predictive of birth ≤28 weeks (Kindinger IPD meta-analysis) – screen from 18 weeks; repeated measures not useful

3. fFN not recommended by NICE in multiple pregnancy (unlike singletons)

4. Cervical cerclage not recommended in twins – no benefit, trend to harm (↑RDS, ↑low birthweight with US-indicated cerclage)

5. Vaginal progesterone: no benefit in unselected twins; possible benefit only in short cervix ≤25 mm subgroup; no long- term infant harm (STOPPIT follow-up)

6. Arabin pessary: conflicting evidence, possible benefit in short cervix (PECEP-Twins) but research use only, not routine practice

7. NICE 2011: do NOT routinely use bed rest, IM/vaginal progesterone, cerclage, oral tocolytics, or pessary in twin/triplet pregnancy

8. No trials compare these interventions head-to-head; share uncertainty with women, offer trial participation (STOPPIT 2, C- STICH, etc.)

EVIDENCE TIERS AT A GLANCE

Possible benefit in short cervix: vaginal progesterone (perinatal outcome), Arabin pessary (PECEP-Twins), cerclage ≤15mm

NICE: avoid routinely – bed rest, IM/vaginal progesterone, cerclage, oral tocolytics, pessary

ABBREVIATION KEY

PTB — preterm birth SET — single embryo transfer

NICE — National Institute for Health and Care Excellence ART — assisted reproduction technology

fFN — fetal fibronectin IVF — in vitro fertilisation

IPD — individual patient data MBRRACE-UK — Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries RCT — randomised controlled trial TAMBA — Twin and Multiple Birth Association RR — relative risk JLA PSP — James Lind Alliance Preterm Birth Priority Setting OR / aOR — odds ratio / adjusted odds ratio Partnership CI — confidence interval GTG — Green-top Guideline (RCOG) CRH — corticotrophin-releasing hormone

Source: The Obstetrician & Gynaecologist (TOG), RCOG journal — Murray SR et al. Spontaneous preterm birth prevention in multiple pregnancy. TOG 2018;20:57–63. doi:10.1111/tog.12460

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