Multicenter randomized trial of cerclage for preterm birth prevention in high-risk women with shortened midtrimester cervical length.
OBJECTIVE
The objective of the study was to assess cerclage to prevent recurrent preterm birth in women with short cervix.


METHODS
Women with prior spontaneous preterm birth less than 34 weeks were screened for short cervix and randomly assigned to cerclage if cervical length was less than 25 mm.


RESULTS
Of 1014 women screened, 302 were randomized; 42% of women not assigned and 32% of those assigned to cerclage delivered less than 35 weeks (P = .09). In planned analyses, birth less than 24 weeks (P = .03) and perinatal mortality (P = .046) were less frequent in the cerclage group. There was a significant interaction between cervical length and cerclage. Birth less than 35 weeks (P = .006) was reduced in the less than 15 mm stratum with a null effect in the 15-24 mm stratum.


CONCLUSIONS
In women with a prior spontaneous preterm birth less than 34 weeks and cervical length less than 25 mm, cerclage reduced previable birth and perinatal mortality but did not prevent birth less than 35 weeks, unless cervical length was less than 15 mm.
Owen
John
J
Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, AL 35249-7333, USA.
Hankins
Gary
G
Iams
Jay D
JD
Berghella
Vincenzo
V
Sheffield
Jeanne S
JS
Perez-Delboy
Annette
A
Egerman
Robert S
RS
Wing
Deborah A
DA
Tomlinson
Mark
M
Silver
Richard
R
Ramin
Susan M
SM
Guzman
Edwin R
ER
Gordon
Michael
M
How
Helen Y
HY
Knudtson
Eric J
EJ
Szychowski
Jeff M
JM
Cliver
Suzanne
S
Hauth
John C
JC
D000328:Adult; D023802:Cerclage, Cervical; D002584:Cervix Uteri / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D011247:Pregnancy; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D047928:Premature Birth / Q000517:prevention & control*; D055502:Secondary Prevention; D016216:Ultrasonography, Prenatal; D055815:Young Adult