We are often asked which is best; fresh or frozen embryo transfer. At Fertility Plus, we often favour frozen embryo transfers as this allows us to manage the timing better, but let’s understand a bit more about the evidence behind fresh and frozen transfers.
A large study published in a New England Journal of Medicine in January 2018 using women in China who did not have polycystic ovaries in their first IVF cycle between 20 and 35, had a stimulation and were given an HCG trigger. Of these women, 1077 had a frozen transfer and 1080 had a fresh transfer, results showed no difference between the live birth rates between fresh (50%) and frozen transfer (49%). The first trimester loss (miscarriage) was similar, though in a frozen cycle the second trimester loss was significantly lower at 1.5 per cent compared to 4.5 per cent fresh embryo transfer.
Whilst showing no significant difference between fresh and frozen in the case of women without polycystic ovaries, in the cases of polycystic ovaries freezing of embryos would significantly improve pregnancy rates.
The advantage of a frozen cycle is whereby the acute stage of hormonal treatments are phased out and embryo transfer is done at a much better time when the ovaries do not have to work extra, hence at Fertility Plus we generally favour frozen embryo transfer.