Background Diabetes in pregnancy accounts for a disproportionately high caesarean section (CS) rate. Pursuant to our previous in vitro laboratory findings of impaired uterine contractility in diabetics (DM), we hypothesised that more emergency C/S in DM are secondary to delay in the first stage of labour reflecting poor uterine function.

Methodology We conducted a case control retrospective study at Liverpool Womens' Hospital over a 10 -year period from January 2001 to January 2011. Of

73 560 deliveries, 1183 were diabetic (DM) pregnancies. We compared delivery outcomes with 1099 non-DM controls matched for age, parity and previous C/S.

Results The C/S rate was higher in DM compared to controls; the overall CS rate was 65% in type 1 DM (table 1). There was a higher number of C/S for failed induction and C/S due to delay in first stage in DM patients including DM with normal BMI (table 2).

Conclusion These results suggest that even accounting for differences in BMI, diabetic women had an increased rate of emergency C/S due to delay in the first stage of labour compared to non-DM, supporting the laboratory findings of deficient myometrial contractility.