hello Welcome to HCM.
the report just signifies abortion/ retained products of conception. In case of any natural or unnatural abortion, the clinician and pathologist want to rule out a molar pregnancy
. That is why they look for abnormal trophoblastic proliferation and centre of villi for something called as cistern formation.
Your wife's report does not give any indication of mole. So, you can be assured on that. However, it is not possible to guess cause of abortion every case by histopathology.
Hope this helps.