One embryo increases the chance of having a healthy baby

Transferring one rather than multiple fertilized donor eggs doubles the chances of a healthy birth. Using In vitro fertilisation IVF increases the odds of having twins or multiples birth which increases the likelihood that the babies will be born premature and underweight.

Many women choose to have multiple embryos transferred in IVF to improve their chances of getting pregnant. In traditional IVF, using fresh eggs, the donor egg is immediately fertilized with a semen sample and then inserted into the uterus of the mother.

For the process to work, the egg donor and recipient have to have their hormonal schedules synced up. With more moving parts, IVF with fresh eggs can take more time, patience, work and money. Frozen eggs can be cryogenically stored for up to 15 years, and are ready to be fertilized as soon as they have thawed.

Egg-freezing is now a commercially available service, but using them for IVF was still an experiment. Cryobanks have touted the practice as just as effective, affordable and simpler than the use of live eggs. Using frozen- bank eggs has no negative outcomes compared to using fresh eggs. Fresh donor eggs are slightly more likely to successfully implant in the recipient’s uterus and result in a live birth, but the outcome is not clinically significant.

There are elevated risks for multiple births, and babies that are premature and have low birth rates for both forms of IVF, but especially for those who use fresh donor eggs. Only one embryo should be transferred at a time because multiple births are at risk for premature birth or low birth weights.
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