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 77,721 ART treatment cycles reported from Australian and New Zealand clinics in 2015 (71,479 and 6,242 respectively) representing a 5.6% increase in Australia and 6.0% increase in New Zealand on 2014. This represented 14.4 cycles per 1,000 women of reproductive age (15–44 years) in Australia, compared with 6.5 cycles per 1,000 women of reproductive age in New Zealand. Women used their own oocytes or embryos (autologous cycles) in 94.5% of treatments. Embryos that had been frozen and thawed were used in 37.4% of autologous cycles.
There were 39,006 women who undertook 73,481 autologous fresh and/or thaw cycles in Australia and New Zealand in 2015. On average, 1.9 fresh and/or thaw cycles per woman were undertaken in 2015, with more cycles per woman in Australia (1.9 cycles per woman) than in New Zealand (1.6 cycles per woman). The number of cycles where embryos were selected using preimplantation genetic testing (PGT) increased from 3,488 in 2014 to 5,773 in 2015 (65.5% increase)
Over the last five years there has been an increasing trend in the proportion of cycles where all oocytes or embryos are cryopreserved for potential future use (freeze-all cycles) from 5.0% of initiated fresh cycles in 2011 to 17.2% of initiated fresh cycles in 2015. This practice is used for a variety of reasons, including reducing the risk of ovarian hyperstimulation syndrome (OHSS), improving endometrial - embryo synchronicity, as part of a PGT cycle, for fertility preservation, or as a deliberate treatment option used by some clinicians.