Patient and IVF characteristics influence blastocyst development
MedWire News: Live births after IVF with blastocyst-stage embryo transfer (ET) are associated with young women who have good ovarian reserve and increasing numbers of total and good-quality blastocysts available, US study results show.
Blastocyst transfer is associated with "increased implantation and live-birth rates compared with cleavage-stage ETs," explain Bradley Van Voorhis and colleagues from the University of Iowa in Iowa City.
However, blastocyst development rates can vary, they report.
Thus, the team correlated patient and IVF cycle characteristics with blastocyst development and pregnancy outcomes in a cohort of 529 couples undergoing IVF with extended embryo culture.
The patient and IVF cycle variables most significantly associated with good or excellent blastocyst formation were younger female age, higher parity, and decreased gonadotropin used during ovarian stimulation.
Variables most associated with a live birth were younger female age (odds ratio [OR] = 1.76 for women under 30 years versus 36 years or more), a higher antral follicle count (OR = 3.64 for more than 20 vs less than 11), and the absence of male factor infertility (OR = 0.66 vs presence of male factor).
The findings may be helpful in selecting the best candidates for single blastocyst transfer, write Van Voorhis et al, while reducing the risks associated with multiple pregnancy.
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By Sarah Guy