An analysis of @ placental samples representing different gestational stages showed ( @ ) no significant differences in beclin-@ , DRAM , and LC@B-II levels in placentas between early and mid-gestation , and late gestation with vaginal delivery ; ( @ ) placentas from late gestation with cesarean section had lower levels of LC@B-II compared to early and mid-gestation , and late gestation with vaginal delivery ; levels of DRAM were also lower compared to placentas from early and mid-gestation ; and ( @ ) using explant cultures , villous tissues from early and late gestation had similar rates of autophagic flux under physiological oxygen concentrations .