Ms Neri said: "Freezing embryos as part of fertility treatment has become a fundamental part of assisted reproduction technology. We found no differences in the ability of embryo generated by IVF or ICSI to implant, even after undergoing the stress of cryopreservation. We were unable to confirm a significant benefit of the unmedicated cycle on the neonatal outcome of the cryopreserved embryos; the difference in malformation rates was small.
"The original premise of the study was to identify a difference in neonatal outcome while in the presence or absence of infertility medication, with the assumption that the unmedicated cycles would generate better offspring outcomes. Interestingly, we did not see any clear difference in neonatal outcomes between the medicated and unmedicated groups. From our study, the combination of exposure to cryopreservation and medications or both did not significantly impair offspring outcome."
The malformations ranged from heart defects to defects caused by hereditary factors and sporadic genetic mutations or interactions. However, Ms Neri said: "They were within the spectrum of malformations observed in newborns in the general population."
As there was no statistical difference between the medicated and unmedicated cycles, Ms Neri said that it was not possible to say that medicated cycles were associated with higher rates of malformations, or, if they were, what mechanism might be responsible.
"Our study reported none of the specific abnormalities linked to male factor infertility, medications or other environmental triggers such as extended in vitro culture, which have been reported by other studies," she said.
"When you think about it, the reproductive medical field has created a new sub-population. These children are now reaching puberty and their fertility status still remains to be assessed. Therefore, the continuous monitoring of children g
|Contact: Mary Rice|
European Society for Human Reproduction and Embryology