Table 2.
Studies reporting the use of reinforcing cerclage.
| Study | Design | Sample Size | Average cervical length at diagnosis (mm) | Cerclage type‡ | Mean gestational age (weeks) initial cerclage | Mean gestational age (weeks) additional cerclage |
Total number sutures placed |
Mean latency to delivery (weeks) | Mean gestational age (weeks) at delivery | Outcome | Overall rate of PTB |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Fox et al., 1998 [15] | Prospective cohort | 12/26 | n/a | McDonald | 14* | 20 (18–24) | 2–4 | 13 (4–19) | 34 (22–39) | PTB < 37 wga LB |
75% (<37) |
| Baxter et al., 2005 [14] | Retrospective cohort | 5/24 | 14.3 ± 3.6 | McDonald | 124/7 | 191/7 | 2 | 14/7 | 20.8 ± 2.7 | PTB < 35 wga PTB < 24 wga |
100% (<35) 80% (<24) |
| Simcox and Shennan, 2012 [16] | Retrospective cohort | 13/25 | 7.2 (0–15) | McDonald | 145/7 | 193/7 | 2 | 64/7 | 260/7 ± 5 1/7 | PTB < 32 wga PTB < 24 wga |
92% (<32) 38% (<24) |
| Song et al., 2011 [17] | Retrospective cohort | 11/22 | n/a | McDonald | 17.0 ± 2.9 | 21.7 ± 2.3 | 2 | 5.1 ± 4.2 | 26.8 ± 5.0 | LB BW |
n/a: not available, PTB: preterm birth, wga: weeks gestational age, LB: livebirth, and PM: perinatal mortality.
*Documented history-indicated cerclage was performed at 14 weeks gestation. Fifteen cases did not have documented gestational ages at initial cerclage placement.