Cord blood acid-base status at delivery after successful external cephalic version

This study was designed to evaluate whether cord blood acidosis is more likely in infants born after successful external cephalic version.

This retrospective cohort study included 89 singleton deliveries with successful version performed over a 2-year period. Their cord blood acid-base parameters were compared to 89 pregnancies with spontaneous cephalic presentation (control group).

There was no significant difference between the version and control groups in birthweight and Apgar scores. There was no difference between the version and control groups in cord arterial pH (7.26 vs. 7.26), arterial pCO(2) (7.04 vs. 7.09 kPa), arterial pO(2) (2.34 vs. 2.59 kPa), arterial base excess (-5.59 vs. -5.64 mmol/L), venous pH (7.32 vs. 7.33), venous pCO(2) (5.73 vs. 5.63 kPa), venous pO(2) (3.86 vs. 3.84 kPa), or venous base excess (-5.03 vs. -5.12 mmol/L). There was also no significant difference in the number of fetuses with cord arterial pH <7.20 between the two groups.

Neonates delivered after successful external cephalic version are not more likely to be born with acidosis. Our study provides further support for the safety of external cephalic version for term breech pregnancies.