Six year follow-up of cryopreserved human embryos1

In 1987, we became aware of the importance of remaining in contactwith couples whose embryos had been cryopreserved for >1year. As a result, a questionnaire was designed to follow thefate of these embryos. Of 407 couples with cryopreserved embryos,262 couples opted to use them within 1 year with the intentionof fulfilling a parental plan. The remaining 145 couples werequestioned by six successive questionnaires sent out between1987 and 1992.By the end of the study, 336 of the 407 couples(82.5%)had chosen to utilize their embryos in a parental plan.In most cases, the maximum delay of response (5 years accordingto the Council of State) was respected. The remaining 71 couples(17.5%) either abandoned the parental plan or had not givenany information by the end of the study. Initially, anonymousdonation to another couple was chosen in preference to destroyingthe surplus embryos (32 versus 18 couples, P < 0.05). Latterly,however, these differences have balanced out (24 versus 28,not significant). Only those couples who initially opted todonate embryos to another couple changed their attitude in lateryears. In the long run, 62 couples decided not to pursue theirparental plan; of these, 24 couples chose to make a gift toanother couple, 28 couples opted for destruction,and 10 choseto make a gift to research. Nine couples (out of 71) declinedto make a decision, but they had all achieved a pregnancy duringan in-vitro fertilization (IVF) attempt.Three of these werelost to follow-up, i.e. 0.7% of all couples benefiting fromthe freezing technique.