[The comparative value of ultrasound examinations and quantitative determinations of chorionic gonadotropin in the differential diagnosis of the disturbed early pregnancy (author's transl)].
Lichtenegger W, Weiss PA.
Geburtshilfe Frauenheilkd. 1975 Jun;35(6):467-74.
PMID:1175896
Urinary retention caused by impaction of leiomyoma in pregnancy.