Predictive Factors for Delivery within 7 Days after Successful 48-Hour Treatment of Threatened Preterm Labor.
Objective The aim of this study was to assess which characteristics and results of vaginal examination are predictive for delivery within 7 days, in women with threatened preterm labor after initial treatment. Study Design A secondary analysis of a randomized controlled trial on maintenance nifedipine includes women who remained undelivered after threatened preterm labor for 48 hours. We developed one model for women with premature prelabor rupture of membranes (PPROM) and one without PPROM. The predictors were identified by backward selection. We assessed calibration and discrimination and used bootstrapping techniques to correct for potential overfitting. Results For women with PPROM (model 1), nulliparity, history of preterm birth, and vaginal bleeding were included in the multivariable analysis. For women without PPROM (model 2), maternal age, vaginal bleeding, cervical length, and fetal fibronectin (fFN) status were in the multivariable analysis. Discriminative capability was moderate to good (c-statistic 0.68; 95% confidence interval [CI] 0.60-0.77 for model 1 and 0.89; 95% CI, 0.84-0.93 for model 2). Conclusion PPROM and vaginal bleeding in the current pregnancy are relevant predictive factors in all women, as are maternal age, cervical length, and fFN in women without PPROM and nulliparity, history of preterm birth in women with PPROM.
Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, The Netherlands.
Carolien
C
Roos
Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands.
Ewoud
E
Schuit
Department of Obstetrics and Gynecology, Maastricht University Medical Center, GROW School for Oncology and Developmental Biology, Maastricht, The Netherlands.
Hubertina C J
HC
Scheepers
Department of Obstetrics and Gynecology, Leiden University Medical Center, Leiden, The Netherlands.
Kitty W M
KW
Bloemenkamp
Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, The Netherlands.
Antoinette C
AC
Bolte
Department of Obstetrics and Gynecology, Erasmus Medical Center, Rotterdam, The Netherlands.
Hans J J
HJ
Duvekot
Department of Obstetrics and Gynecology, Isala Clinics, Zwolle, The Netherlands.
Jim
J
van Eyck
Department of Neonatology, Academic Medical Center, Amsterdam, The Netherlands.
Joke H
JH
Kok
Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands.
Anneke
A
Kwee
Department of Obstetrics and Gynecology, Ziekenhuis Rijnstate, Arnhem, The Netherlands.
Ashley E R
AE
Merién
Clinical Research Unit, Academic Medical Center, Amsterdam, The Netherlands.
Brent C
BC
Opmeer
Department of Obstetrics and Gynecology, University Medical Center Utrecht, Utrecht, The Netherlands.
Martijn A
MA
Oudijk
Department of Obstetrics and Gynecology, Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands.
Mariëlle G
MG
van Pampus
Department of Obstetrics and Gynecology, Amphia Hospital, Breda, The Netherlands.
Dimitri N M
DN
Papatsonis
Department of Obstetrics and Gynecology, Máxima Medical Center, Veldhoven, The Netherlands.
Martina M
MM
Porath
Department of Obstetrics and Gynecology, University Medical Center, Groningen, The Netherlands.
Krystyna M
KM
Sollie
Department of Obstetrics and Gynecology, Maastricht University Medical Center, GROW School for Oncology and Developmental Biology, Maastricht, The Netherlands.
Marc E A
ME
Spaanderman
College voor Zorgverzekeringen, Diemen, The Netherlands.
Sylvia M C
SM
Vijgen
Department of Obstetrics and Gynecology, Maastricht University Medical Center, GROW School for Oncology and Developmental Biology, Maastricht, The Netherlands.
Christine
C
Willekes
Department of Obstetrics and Gynecology, Radboud University Medical Center, Nijmegen, The Netherlands.
Fred K
FK
Lotgering
Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands.
Joris A M
JA
van der Post
The Robinson Institute, School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, Australia.
Ben Willem J
BW
Mol
maintenance tocolysis; predictive factors; preterm delivery