The effect of gestational age and cervical length measurements in the prediction of spontaneous preterm birth in twin pregnancies : an individual patient level meta-analysis

OBJECTIVE: To assess the effect of gestational age (GA) and cervical length (CL) measurements at transvaginal ultrasound (TVUS) in the prediction of preterm birth in twin pregnancy. DESIGN: Individual patient data (IPD) meta-analysis. SETTING: International multicentre study. POPULATION: Asymptomatic twin pregnancy. METHODS: MEDLINE and EMBASE searches were performed and IPD obtained from authors of relevant studies. Multinomial logistic regression analysis determined probabilities for birth at ≤28(+0) , 28(+1) to 32(+0) , 32(+1) to 36(+0) , and ≥36(+1) weeks as a function of GA at screening and CL measurements. MAIN OUTCOME MEASURES: Predicted probabilities for preterm birth at ≤28(+0) , 2…