From 1 August 1993 until 30 September 1994, 69 couples suffering from azoospermia underwent testicular sperm extraction and intracytoplasmic sperm injection. In 50 couples with obstructive azoospermia a total of 631 metaphase-II oocytes were injected after testicular sperm extraction yielding a 2-PN fertilization rate of 57%. In female patients <40 years of age an ongoing pregnancy rate per transfer of 42% (14/33) was obtained. So far, eight healthy babies have been born, including two singletons and three twin gestations. In 19 couples with non-obstructive azoospermia a total of 264 metaphase-II oocytes were injected after testicular sperm extraction, yielding a 2-PN fertilization rate of 58%. An ongoing pregnancy rate per transfer of 31% (5/16) was established. So far, six healthy babies have been born including one singleton, one twin and one triplet gestation.