Reproductive Technology

An alternative to IVF and intrauterine embryo transfer is gamete intrafallopian transfer (GIFT), introduced more than twenty years ago. In this procedure, the egg and sperm are collected as they would be for IVF procedures. However, instead of allowing fertilization to take place in a culture dish, the egg and sperm are transferred surgically into the woman's fallopian tube. This allows fertilization to occur in the fallopian tube, just as occurs in a natural pregnancy. The transfer can only be performed in women with healthy and functional fallopian tubes, and the sperm used for fertilization must be completely normal and capable of swimming.

After the transfer is made, doctors have no way of knowing if normal fertilization actually takes place until an embryo has implanted in the uterine wall. However, the procedure's success rate (35%) is higher than the success rate for IVF. Another related technique is zygote intrafallopian transfer, in which the egg is fertilized in vitro and the zygote is transferred surgically into the fallopian tube. Other techniques include tubal embryo transfer, in which an embryo already undergoing cleavage is transferred.