Objective A comparison of two protocols for the management of women with history of previous preterm birth.

Method A comparative observational study was performed, to compare outcomes of women attending a preterm labour clinic, who were managed on a high intervention protocol in 2003–2007 and a protocol with intervention only with defined criteria in 2008–2010. Outcome measures were the rate of spontaneous preterm birth at <24, 24 to 33+6, 34 to 36+6 and >37+0 weeks gestation. Relative risk and 95% CIs were calculated for dichotomous data within the sub-groups of previous cervical surgery, treated with progesterone only, cerclage and no treatment.

Results 392 patients in the 2008–2010 cohorts were compared with 281 patients between 2003 and 2007. There were more patients in the previous cervical surgery or no intervention group for 2008–2010 cohorts. There was no significant difference in the rates of preterm birth by gestation in the progesterone only sub-group. Cervical cerclage in the event of a significantly shortened cervix either after treatment with or without progesterone showed a significant reduction in birth before 37 week for 2008–2010 cohort. The 2008–2010 protocol resulted in less birth before 34 weeks gestation, despite a 53% intervention rate in the 2003–2007 cohorts when compared to 23% in the 2008–2010 cohort.

Conclusion The results from this study show that 2008–2010 protocol of minimal intervention apart from serial assessment of cervical length and intervention only with defined criteria results in similar and sometimes better outcomes than with a protocol of high intervention.