Trial of labor after cesarean and contribution of pelvimetry in the prognosis of neonatal morbidity

Abstract Introduction To estimate the association between an abnormal pelvic dimension at pelvimetry and the occurrence of severe neonatal morbidity after trial of labor after cesarean (TOLAC). Materials and methods Retrospective observational cases-controls study conducted at a level 3 maternity units between 2006 and 2016. Included women were patient with trial of labor after one previous cesarean section, alive singleton fetus in cephalic presentation ≥ 37 W G. Two groups were compared according to pelvic mesures at pelvimetry: pelvic dimension considered as abnormal, defined by Conjugate Diameter Results 2474 women were included. 863 (34.8 %) have a normal pelvic dimension and 1611 (65.2 %) an abnormal. Characteristics of labor were similar in two groups. Success of TOLAC was 84.7 % in normal pelvic group and 64.6 % in abnormal dimension of pelvic group. Neonatal morbidity was similar between two groups (1.7 % in normal pelvic dimension group versus 2.3 % in abnormal pelvic dimension group, p = 0.26; crude OR: 1.39 (0.77–2.49) ; adjusted OR : 0.93 (0.51–1.68)). Discussion There were no association between pelvic dimension at pelvimetry and neonatal morbidity. In case of abnormal pelvic dimension, a combination of more prudence, and stringent user practices, achieve a high rate of vaginal delivery and a neonatal morbidity comparable to the normal pelvic dimension group.