Using a suspension of fallopian tube fluid, University of Pennsylvania investigators have achieved in vitro fertilization in over 60% of rabbit sperm-ova incubations.
The laboratory procedure enables direct observation of fertilization and early cellular cleavage—in much the same environment as occurs in vivo—according to Shuetu Suzuki, MD, and Luigi Mastroianni, Jr., MD.
Although various investigators have accomplished in vitro fertilization during the past 15 years, they used artificial suspension medias.
"But, in most mammalian species, fertilization occurs in the fallopian tube," Dr. Mastroianni told The Journal recently. "The influence of tubal secretions remained an unanswered question."
Results of the fertilization experiments suggest that "tubal fluid contains all the ingredients requisite to fertilization," the Penn research team agrees.
In one series, 63.7% or 79 of 124 ova were fertilized and achieved cleavage. A second cleavage was observed in 12 of the 79.
Previously, fertilizations of 30% to 60% had been the