[Letter from America. Mid-trimester amniocentesis].
D000293:Adolescent; D000328:Adult; D000649:Amniocentesis; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis; D012306:Risk; D014481:United States