Most female pups around 8-9 mos go into their 1st heat,yes it IS poss. for a first timer to get pregnant at 8 mos,trust me I have a 9 mos old rotti at home expecting in about 4 weeks!!!!!
We rescued her at 8 mos to bring home and join our 10 mos old male,only to find out in the car that she was in heat,it was almost immposs. to keep them apart,with his neuter date only days away we thought we were safe. Not so true.Now our babies are having babies...although on her prenatal check up it is still unclear if she is having psudo or fakr pregnancy,it is hard to tell in young moms for they can carry very high,we will know more in a week or so at next visit.
hope this helps!!!! rotti mom shari