Current practices in the prediction and prevention of preterm birth in patients with higher-order multiple gestations

We sought to determine the interventions utilized by maternal-fetal medicine specialists in the prediction and prevention of preterm labor in higher-order multiple (HOM) gestations.

Online questionnaires and email surveys were sent to all the maternal-fetal medicine specialists in Canada (n=122). Questionnaire items included interventions physicians routinely recommended for HOM gestations including: (1) bed rest; (2) cervical length measurement on transvaginal ultrasound; (3) corticosteroids use; (4) cerclage; and (5) tocolytic therapy.

Response rate was 66% (81/122), with 68% of respondents in practice for >10 years. Of physicians, 91% did not routinely recommend bed rest (95% confidence interval [CI], 84.7-97.2). In all, 82% (95% CI, 73.63-90.4%) recommended routine cervical length assessment with 32.3% (95% CI, 20.7-43.2) and 37.1% (95% CI, 25.3-48.6) of this group suggesting assessment at 16-18 and 19-21 weeks, respectively. Frequency of assessment varied from biweekly (53.3%; 95% CI, 40.9-65.0), to monthly (23.3%; 95% CI, 12.8-33.1), to a single measurement repeated only if abnormal (12.5%; 95% CI, 4.5-20.8). In all, 28% (95% CI, 18.2-37.8) recommended routine administration of corticosteroids for lung maturation. Timing of administration varied, with 24% initiating steroids between 24-26 weeks, 59% between 27-28 weeks, and 17% after 28 weeks. None reported routine cerclage placement. However, 71% (95% CI, 61.1-80.8) would perform cerclage based on history or ultrasound. Of respondents, 81% (95% CI, 72.4-89.5) would consider using tocolytic agents for threatened preterm labor including calcium channel blockers (94%), nonsteroidal antiinflammatory drugs (5%), and nitroglycerin transdermal patch (24%).

The variable practice guidelines and paucity of data for management of HOM pregnancy places the onus on individual practitioners to develop their own management schemes. This results in heterogeneous management, which is based on conflicting international guidelines, studies, expert opinion, or past experience.