(medicine) A procedure for obtaining amniotic fluid from a pregnant animal, by inserting a hollow needle through the abdominal wall and into the amniotic sac. Used in diagnosing possible genetic defects and/or obstetric complications.
1999, Matt Ridley, Genome, Harper Perennial 2004, p. 287:In most countries amniocentesis is now offered to – perhaps even imposed on – all older mothers, to check whether the foetus carries an extra chromosome.