title: Spontaneous abortion in proven intact pregnancies.
mesh_terms: D000022:Abortion, Spontaneous / Q000453:epidemiology*; D000328:Adult; D005260:Female; D006801:Humans; D009426:Netherlands; D011247:Pregnancy; D011296:Prenatal Diagnosis; D011446:Prospective Studies; D012306:Risk; D014463:Ultrasonography