amniocentesis

am·nio·cen·te·sis

noun \ˌam-nē-ō-(ˌ)sen-ˈtē-səs\

plural am·nio·cen·te·ses \-ˌsēz\

Definition of AMNIOCENTESIS

: the surgical insertion of a hollow needle through the abdominal wall and into the uterus of a pregnant female to obtain amniotic fluid especially to examine the fetal chromosomes for an abnormality and for the determination of sex

Illustration of AMNIOCENTESIS