THE CASE FOR TRIAL OF LABOR IN THE PATIENT WITH A PRIOR LOW-SEGMENT VERTICAL CESAREAN INCISION

OBJECTIVE: Our purpose was to review recent obstetric literature detai ling the subsequent delivery experience of patients with a prior low-s egment Vertical cesarean incision and to derive recommendations for pr actice on the basis of this information. STUDY DESIGN: Ten studies tha t included information about pregnancy outcome in patients with prior low-segment Vertical cesarean operations were retrieved and reviewed f rom the American obstetric literature since 1981 and from a review of all abstracts presented annually since 1981 to the Society of Perinata l Obstetricians. RESULTS: Altogether, information about subsequent pre gnancy outcome for 382 patients with prior low-segment Vertical cesare an delivery was available for analysis. Among the 372 patients with co mplete patient population information, vaginal delivery was safely acc omplished in 306 (82%). Four uterine ruptures (1.05%) have been report ed, only one of which occurred after a single prior unextended low-seg ment vertical cesarean incision. Two ruptures occurred elsewhere on th e lateral or posterior aspect of the uterus in subsequent pregnancies, and the fourth rupture occurred at the juncture of prior low vertical and transverse incisions. No perinatal mortality or permanent perinat al morbidity was encountered with these pregnancies. CONCLUSIONS: In t he otherwise uncomplicated pregnancy the patient with one previous non extended low-segment vertical cesarean incision should be considered t o have a prior low-segment scar and as such be a candidate for trial o f labor in her current singleton pregnancy. The same care, counseling, and caution should be exercised for this patient as for one with a pr ior low-segment transverse incision.