Assisted reproductive technology (ART) is a group of procedures that involve the in vitro (outside of body) handling of human oocytes (eggs) and sperm or embryos for the purposes of establishing a pregnancy. Each ART treatment involves a number of stages and is generally referred to as an ART treatment cycle. The embryos transferred to a women can either originate from the cycle in which they were created (fresh cycle) or be frozen and thawed before transfer (thaw cycle).
There were 71,516 ART treatment cycles reported from Australian and New Zealand clinics in 2013 (66,143 and 5,373 respectively) representing a 1.9% increase in Australia and 3.8% increase in New Zealand on 2012. This represented 13.7 cycles per 1,000 women of reproductive age (15–44 years) in Australia, compared with 5.9 cycles per 1,000 women of reproductive age in New Zealand. Women used their own oocytes or embryos (autologous cycles) in 95.1% of treatments. Embryos that had been frozen and thawed where used in 36.6% of autologous cycles.
There were 37,192 women who undertook 67,980 autologous fresh and/or thaw cycles in Australia and New Zealand in 2013. On average, 1.8 fresh and/or thaw cycles per woman were undertaken, with more cycles per woman in Australia (1.9 cycles per woman) than in New Zealand (1.5 cycles per woman). The number of cycles where PGD was performed increased from 2,294 in 2012 to 2,740 in 2013 (19.4% increase), representing 4.4% of cycles in which embryos were created or thawed.
The average age of women undergoing autologous cycles was 35.9. In contrast, the average age of women undergoing ART treatment using donor oocytes or embryos was approximately five years older at 40.7. Approximately, one in four (26.8%) women who underwent an autologous cycle in 2013 was aged 40 or older. The average age of male partners was 38.3, with one-third (35.5%) aged 40 or older.
Of the 71,516 initiated cycles, 23.8% (17,054) resulted in a clinical pregnancy and 18.2% (12,997) in a live delivery. The overall clinical pregnancy rate for cycles reaching embryo transfer was 31.0%. The live delivery rate per initiated fresh cycle was 16.3% and per fresh embryo transfer cycle was 23.7%. The live delivery rate per initiated thaw cycle was 22.0% and per thaw embryo transfer cycle was 23.6%.
There was a higher live delivery rate in younger women. For women aged under 30, the live delivery rate was highest for both autologous fresh and thaw cycles (27.2% and 27.8% respectively). For women aged over 44, the live delivery rate was 1.2% and 5.4% per initiated autologous fresh and thaw cycles respectively.
The live delivery rate per day 2–3 embryo transfer (cleavage stage) was 16.0% and per day 5-6 embryo transfer (blastocyst) was 28.4%. However, caution should be taken when comparing success rates following cleavage stage embryo and blastocyst transfer. Patient characteristics and prognosis are different between these groups, and generally fewer embryos are available for transfer and cryopreservation when blastocyst culture is used.
There were 13,939 babies born (including 13,715 liveborn babies) following ART treatment in 2013. Of these, 12,637 (90.7%) were from Australian clinics and 1,302 (9.3%) from New Zealand clinics. Over three-quarters of the liveborn babies (77.5%) were full-term singletons of normal birthweight.
ANZARD includes data items that make it possible to follow a woman’s consecutive ART treatment cycles. A cohort of 14,887 women was followed from the start of their first autologous fresh cycle during 2011, through subsequent fresh and thaw cycles until December 2013 or until they achieved a live delivery. The cycle-specific live delivery rate per initiated cycle for all women was 20.6% in their first cycle, and around 10% after seven cycles. For women aged 30-34 the cycle-specific live delivery rate was 28.1% in the first cycle and around 20% in the following nine cycles. Of women who did not achieve a live birth in a specific cycle, approximately one in four did not return for further ART treatment.
Treatment trends in the last five years include a shift from cleavage stage transfers to blastocyst transfers from 49.8% in 2009 to 61.1% in 2013; an increase in vitrification as a cryopreservation method from 33.2% of thaw blastocyst transfer cycles in 2009 to 82.9% in 2013; and continued use intracytoplasmic sperm injection (ICSI) in over 60% of embryo transfer cycles.
There was also a trend over the last five years of fresh cycles not proceeding to embryo transfer, from 23.4% of initiated cycles in 2009 to 32.5% of initiated cycles in 2013. The proportion of embryo transfer cycles transferring a cryopreserved embryo increased from 39.3% of cycles in 2009 to 44.7% in 2013.
In the last five years the live delivery rate per fresh embryo transfer cycle ranged from 23.0% to 23.7%, while the live delivery rate per frozen/thaw embryo transfer cycle increased from 18.3% to 23.4%.
Acontinuing trend in ART treatment in Australia and New Zealand has been the reduction in the rate of multiple deliveries, with a 32% decrease from 8.2% in 2009 to 5.6% (5.6% for Australia and 5.2% for New Zealand) in 2013. This was achieved by clinicians and patients shifting to single embryo transfer, with the proportion increasing from 69.7% in 2009 to 79.2% in 2013. Importantly, this decrease in the multiple delivery rate was achieved while live birth rates per embryo transfer increased from 21.2% in 2009 to 23.6% in 2013.