The Maternal-Fetal Medicine Units Cesarean Registry: safety and efficacy of a trial of labor in preterm pregnancy after a prior cesarean delivery.
OBJECTIVE
This study was undertaken to compare success rates of vaginal birth after cesarean (VBAC) delivery, and uterine rupture as well as maternal/perinatal outcomes between women with preterm and term pregnancies undergoing trial of labor (TOL), and to compare maternal and neonatal morbidities in those women with preterm pregnancies undergoing a TOL versus repeat cesarean delivery without labor (RCD).


METHODS
Prospective 4-year observational study of women with a singleton gestation and a prior cesarean delivery at 19 academic centers. Clinical characteristics, maternal complications and VBAC delivery success for those with a preterm (24(0)-36(6) weeks) TOL, preterm RCD and term TOL (> or = 37 weeks) were analyzed.


RESULTS
Among 3119 preterm pregnancies with prior cesarean delivery, 2338 (75%) underwent a TOL. 15,331 women undergoing TOL at term were also analyzed as a control group. TOL success rates for preterm and term pregnancies were similar (72.8% vs 73.3%, P = .64). Rates of uterine rupture (0.34% vs 0.74%, P = .03) and dehiscence (0.26% vs 0.67%, P = .02) were lower in preterm compared with term TOL. Thromboembolic disease, coagulopathy and transfusion were more common in women undergoing a preterm TOL than those at term. Among women undergoing a preterm TOL, rates of uterine dehiscence, coagulopathy, transfusion, and endometritis were similar to those having a preterm RCD. After controlling for gestational age at delivery and race, neonatal outcomes such as Neonatal Intensive Care Unit (NICU) admission, intraventricular hemorrhage, sepsis, and ventilatory support were similar in both groups except for a higher rate of respiratory distress syndrome in those delivered after a TOL.


CONCLUSIONS
The likelihood of VBAC success after TOL in preterm pregnancies is comparable to term gestations, with a lower risk of uterine rupture. Perinatal outcomes are similar with preterm TOL and RCD. TOL should be considered as an option for women undergoing preterm delivery with a history of prior cesarean delivery.
Durnwald
Celeste P
CP
Department of Obstetrics and Gynecology, Ohio State University, Columbus, OH, USA.
Rouse
Dwight J
DJ
Leveno
Kenneth J
KJ
Spong
Catherine Y
CY
MacPherson
Cora
C
Varner
Michael W
MW
Moawad
Atef H
AH
Caritis
Steve N
SN
Harper
Margaret
M
Wapner
Ronald J
RJ
Sorokin
Yoram
Y
Miodovnik
Menachem
M
Carpenter
Marshall
M
Peaceman
Alan M
AM
O'Sullivan
Mary Jo
MJ
Sibai
Baha
B
Langer
Oded
O
Thorp
John M
JM
Ramin
Susan M
SM
Mercer
Brian M
BM
Gabbe
Steven G
SG
D000328:Adult; D005260:Female; D005865:Gestational Age; D006801:Humans; D007752:Obstetric Labor, Premature; D011247:Pregnancy; D011446:Prospective Studies; D012042:Registries; D012449:Safety; D014219:Trial of Labor; D014597:Uterine Rupture / Q000453:epidemiology / Q000517:prevention & control; D016064:Vaginal Birth after Cesarean / Q000009:adverse effects