Influence of microsurgical reanastomosis of the fallopian tube on luminal pH and PO2 and on the fertilization rate and embryo development in the rabbit oviduct.

The luminal pH and PO2 were measured in rabbit oviducts to evaluate the influence of microsurgery on the environment within the fallopian tube before and after resection of a 1 cm ampullary portion with subsequent tubal reanastomosis. While the oxygen tension showed no difference between the operated oviduct (56 +/- 16 mmHg, n = 8) and the control side (53 +/- 13 mmHg, n = 8), there was a significant pH decrease in the oviducts after microsurgery (7.94 +/- 0.10, n = 8, versus 7.75 +/- 0.16, n = 8, p less than 0.0025). In the second part of the experiment the operated animals were induced to ovulate by hCG injection, and artificial insemination was performed at the same time. The number of fertilized and unfertilized oocytes and the stages of embryonic development (64 h post hCG) were compared between the operated and control oviducts. From the operated oviducts a lower number of ova were recovered and a lower rate of fertilization was observed. The data indicate that microsurgery of the rabbit fallopian tube does not disturb the luminal oxygen tension but may cause a lower pH. Ultimately a reduced rate of fertilization and impaired early development were observed.