744 Clinical factors associated with gestational latency in women with twins undergoing physical exam-indicated cerclage

Abstract

A randomized trial demonstrated that, compared to expectant management, physical exam-indicated cerclage (PEIC) reduced preterm birth in twins with advanced cervical dilation < 24 weeks gestational age (GA). However, data are limited to personalize the expected gestational latency after PEIC placement. Thus, we assessed clinical factors associated with gestational latency among pregnant women with twin gestations undergoing PEIC. This single-site retrospective cohort study included all women with a twin gestation who underwent a PEIC and delivered between 2009 and 2018. PEIC was performed in the setting of painless cervical dilation ≥ 1 cm between 16 0/7 and 23 6/7 weeks GA. The primary outcome was gestational latency ≥ 28 days. Generalized linear models using a Poisson error distribution with robust error variances were created. A priori covariates included a history of preterm birth and use of perioperative antibiotics and indomethacin. Other clinical covariates were included based on statistical significance of p < 0.10 on bivariable analyses. Effect modification between clinical variables associated with gestational latency was evaluated using interaction variables. Subgroup analyses were performed for interaction variables significant on multivariable analysis at p < 0.05. 130 women were included. Women who achieved a gestational latency ≥ 28 days had a lower frequency of prolapsing membranes (36.6% v 64.9%, p = 0.003) and cervical dilation ≥ 2 cm (32.3% v. 62.2%, p = 0.002) when compared to those who did not (Table 1). On multivariable analysis, the interaction between prolapsing membranes and cervical dilation was significant (p=0.004). Women with cervical dilation ≥ 2 cm and prolapsing membranes had a lower risk of achieving a gestational latency ≥ 28 days than women with cervical dilation < 2 cm and no prolapsing membranes (aRR 0.51, 95% CI 0.32-0.80, Table 2). Both cervical dilation and prolapsing membranes are associated with gestational latency after PEIC in twin gestations and can be used to counsel women on anticipated clinical outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)