NEW ORLEANS — Patients will not accept elective single embryo transfer as a means of reducing the risk of multiple pregnancy unless it offers them an equal chance of conceiving, compared with the transfer of two embryos, Moniek Twisk said at the annual meeting of the American Society for Reproductive Medicine.
“To reduce the risk of multiple pregnancy it is essential to offer SET [single embryo transfer] that does not negatively affect pregnancy rates,” said Ms. Twisk, a Ph.D. student at Academic Medical Center in Amsterdam. “It is only such an approach that will not jeopardize patient acceptance of SET.”
Her study was a questionnaire-based survey of 244 women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) at two fertility centers in the Netherlands. The questionnaire presented various trade-offs in which either SET or double-embryo transfer (DET) were proposed, with different pregnancy rates and numbers of cycles required to achieve pregnancy.
Patients, who were a mean age of 34 years, with a mean infertility duration of 4 years, were told to assume a 25% chance of multiple pregnancy with DET, and a 1% chance with SET.
The study found that even if patients believed their pregnancy chances were the same with either SET or DET, less than half of them would choose SET to reduce the chance of multiple pregnancy. This may be partly due to the fact that, according to other studies, up to 27% of women undergoing IVF say they would actually prefer to have twins rather than a singleton, she commented.
If the patients were told that SET would lower their chances of pregnancy even fewer said they would choose this option. (See sidebar.)
Patients were then asked to consider their willingness to undergo additional cycles of SET to achieve the same success rate as three cycles of DET (without the risk of multiple pregnancy).
Even if three cycles of SET provided the same success rate as three cycles of DET, less than half said they would choose this option, said Ms.Twisk. If subjects were told that four, five, or six cycles of SET could achieve the same pregnancy rate as DET, even fewer said they would accept this option.
The issue of cost for the extra cycles was not explored in the study, Ms. Twisk said in an interview. In the Netherlands patients are usually reimbursed for the first three cycles of IVF, she said.
The results emphasize “unambiguously the overwhelming dominance of pregnancy as the primary goal of treatment for women undergoing IVF/;ICSI, and the absence of willingness to trade off that goal in order to avoid a multiple pregnancy,” Ms. Twisk said.
SET vs. DET Picks Favor the Latter
Willingness to Consider SET Over DET
▸ With identical pregnancy chances, 54% prefer DET.
▸ If SET reduces chances by 1%, 60% prefer DET.
▸ If SET reduces chances by 3%, 76% prefer DET.
▸ If SET reduces chances by 5%, 85% prefer DET.
Willingness to Equalize Pregnancy Chances With Extra SET Cycles
▸ If three DET cycles = three SET cycles, 54% prefer DET.
▸ If three DET cycles = four SET cycles, 60% prefer DET.
▸ If three DET cycles = five SET cycles, 64% prefer DET.
▸ If three DET cycles = six SET cycles, 65% prefer DET.
Source: Ms. Twisk