title: A single-operator technique for first-trimester chorion biopsy.
mesh_terms: D001707:Biopsy, Needle / Q000295:instrumentation / Q000379:methods*; D002823:Chorion / Q000473:pathology*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis / Q000295:instrumentation / Q000379:methods*; D014463:Ultrasonography