Objective To investigate obstetric outcomes of multiparous pregnancies with advanced maternal age in different inter-pregnancy intervals.Methods A retrospective study was performed in 222 multiparous pregnancies with advanced maternal age from January 1 st 2016 to December 31 st 2016.According to the inter-pregnancy intervals,all cases were divided into four groups:Group A (1-3 years),group B (4-6 years) group C (7-9 years) and group D (≥10 years).The clinical characteristics,complications during pregnancy,maternal and fetal outcomes and duration of labor were compared and analyzed in the four groups.Results The average age of groups was significantly different (P ≤ 0.001).But there was no significant difference in the rate of oxytocin (P =0.465),incidence of gestational diabetes mellitus (P =0.698),pregnancy-induced hypertension (P =0.158),premature rupture of membrane (P =0.542)and postpartum hermorrhege (P =0.124) among the four groups.A total of 212 pregnancies underwent vaginal delivery.In group A,the first stage of labor last (239.16 ± 137.63) min,which was significantly shorted than that in group B [(296.36 ± 124.56) min],group C [(332.81 ± 181.01) min] and group D [(337.19 ±224.02)min,P =0.030].However,the interval of delivery did not prolong the second (P =0.137) and third stage of labor (P=0.079).The neonatal birth weight (P =0.276) and the neonatal sex (P =0.918),as well as admission of neonatal intensive care unit (NICU,P =0.103),were similar among three groups.The rate of neonatal asphyxia in group A and group D was higher than that in group B and group C (P =0.021).Conclusions Although the second and third stage were similar among multiparous pregnancies with advanced maternal age,the first stage of labor last longer in the longer inter-pregnancy interval.Furthermore,the risk of neonatal asphyxia was higher in women with inter-pregnancy interval ≤ 3 years or ≥ 10 years.