PubMed:: ("Abortion, Spontaneous"[Mesh] OR miscarriage[tiab] OR "Abortion, Incomplete"[Mesh] OR incomplete abortion*[tiab])));; Embase.com:: 'spontaneous abortion'/exp OR 'incomplete abortion'/exp OR miscarriage*:ab,ti OR 'incomplete abortion':ab,ti OR 'incomplete abortions':ab,ti;; Cochrane Library:: (abortion* or miscarriage*):ti,ab,kw