Summary

Assisted reproduction technology (ART) treatment characteristics

  • During 2004, 41,904 treatment cycles were started in Australia and New Zealand. Of these, 92.6% (38,823) were in Australia and 7.4% (3,081) were in New Zealand.
  • In Australia, there were 9.0 treatment cycles per 1,000 women of reproductive age (15–44 years). Correspondingly, in New Zealand, there were 3.5 cycles per 1,000 women of reproductive age (15–44 years).
  • For more than half (53.5%) of the ART treatment cycles, non-donor fresh oocytes or embryos were used, for over a third (34.3%) thawed non-donor embryos were used, and for 6.4% oocytes or embryos received from a donor were used.
  • In 2004, 40.5% of cycles with embryo transfer involved the transfer of one embryo, and 56.3% involved the transfer of two embryos.
  • The average age of women undergoing treatment in 2004 was 35.4 years. Their partners were aged on average 37.8 years.
  • The success of non-donor fresh treatment cycles varied by women’s age. Women aged 23–24 years had the greatest success, with 33.5% of cycles with oocyte retrieval resulting in a live delivery. Women aged 40–44 years had a success rate of 7.1%.

Pregnancies, deliveries and births from ART

  • Overall, 8,794 cycles undertaken in 2004 resulted in a pregnancy. Of these pregnancies, 20.0% were less than 20 weeks gestation and 78.8% resulted in births of 20 weeks or more gestational age or 400 grams or more birthweight. There were 7,913 live births and 119 fetal deaths.
  • Fertility centres in Australia reported 89.2% (7,846) of the cycles that resulted in a pregnancy. These resulted in 7,029 live births. Fertility centres in New Zealand reported 10.8% (948) of the cycles that resulted in a pregnancy and these resulted in 884 live births.
  • There were 1,114 (16.1%) cycles that resulted in a twin gestation delivery. For most of these cycles two or more embryos were transferred.
  • For about half (49.7%, 3,448) of the cycles that resulted in a delivery, the method of birth was caesarean section.
  • The average age of women who gave birth was 34.5 years.
  • There were 2,028 (25.2%) babies born to women who had ART treatment in 2004 that were preterm. For singletons 10.9% were preterm and for twins 59.9% were preterm.
  • The average birthweight of live births was 3,054 grams. The proportion of live births that were low birthweight (<2,500 grams) was 20.0%. The proportion of liveborn singletons that were low birthweight was 7.5% and the proportion for twins was 50.0%.
  • There were 155 perinatal deaths reported, of which 36 were neonatal deaths. This represents a perinatal mortality rate of 19.3 deaths per 1,000 births. The perinatal mortality rate for singletons was 16.0 deaths per 1,000 births, and the rate for twins was 26.9 per 1,000 births.
  • There were 2,431 babies born to women who had ART treatment in 2004 in which a single embryo was transferred. This was 30.2% of babies born to women who had ART treatment in 2004. Of these babies, 2,338 (96.2%) were singletons and 93 (3.8%) were multiples.

IUI-donor cycles

  • In 2004, in Australia and New Zealand, there were 3,170 cycles in which IUI using donated sperm (IUIdonor) was undertaken at fertility centres.
  • Of IUI-donor cycles, 12.5% (396) resulted in a pregnancy and 9.7% (307) resulted in a live delivery.
  • There were 24 (7.7%) IUI-donor cycles that resulted in a multiple gestation delivery.
  • Of babies born to women who had an IUI-donor cycle, 15.5% were preterm (<37 weeks gestation).
  • The average birthweight for babies born to women who had an IUI-donor cycle was 3,207 grams.
  • The perinatal death rate for babies born to women who had an IUI-donor cycle was 11.7 deaths per 1,000 births.