Assisted hatching on assisted conception (IVF and ICSI)

Multiple gestation associated with infertility therapy: an American Society for Reproductive Medicine Practice Committee opinion

“…In one case series, assisted hatching also was associated with an increased risk of monozygotic twinning (20). However, a 2009 Cochrane review of four studies with a total of 524 patients concluded that available data were insufficient to determine whether assisted hatching increased the risk of monozygotic twinning (odds ratio [OR] 3.26, 95% confidence interval [CI] 0.14-77.84) (21). A number of studies have concluded that the risk of monozygotic twinning is increased when culture is extended to the blastocyst stage (13).…”

Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary report

“…In contrast, when the blastocelic cavity exits first, the ICM (small space and high viscosity) is still in the zona, resulting in an insufficient flow to push the ICM out. The polarity may be the reason why the effect of AH on recurrent IVF-ET failure is still uncertain (7)(8)(9)(10). AH performed without consideration of the site (i.e., on day 2 or 3) might either promote or inhibit hatching of the blastocyst.…”

“…In the past decade, AH has been offered to older patients as well as to those with frozen-thawed embryos or who have suffered recurrent IVF-ET failure. The effect of AH, however, is still debatable (7)(8)(9)(10).…”

Gamete and Embryo Manipulation

“…[214][215][216][217][218] However, there remains conflicting evidence of an age-related benefit of assisted hatching in patients with advanced maternal age. 219,220 In an unselected population of patients, assisted hatching did not increase pregnancy and implantation rates.…”

“…[221][222][223][224] A recent meta-analysis that included randomized controlled trials of assisted hatching versus no assisted hatching and reported live births, clinical pregnancies, or implantation rates, concluded that there is some evidence that assisted hatching may increase the chance of pregnancy beginning in women for whom IVF has been repeatedly unsuccessful, and possibly in older women. 218 There has been tremendous interest in improving the results of assisted reproduction through transfer of blastocysts after extended culture. Although human blastocysts expand readily in vitro, most blastocysts have hatching problems or cannot completely hatch out of the zona, and subsequently degenerate by day 6 or day 7.…”