Yes and no

I had a retained placenta and PPH with birth 2, birth 3 had no issues whatsoever but birth 4 I had a secondary PPH 2 hours later and lost 1.5lt. The cause of that was due to the uterus relaxing for some unknown reason.
The two events are unrelated so my OB said but after having one PPH it does make you more likely to have another but it's not a given that it will happen.

It is very scary to go through isn't it.