Transperitoneal migration and ovum capture in rabbits

It is not fully understood how eggs are captured by the fallopian tube. The close proximity of tube and ovary, and the movements of the fimbria across the ovarian surface during ovulation, are believed to contribute to ovum pickup. We studied the efficiency of ovum capture when contact between fimbria and ovary is prevented and the extent to which ovum transmigration may contribute to fertility. Unilateral right oophorectomy was performed in 55 rabbits, which were divided into three groups: in Group A, the contralateral oviduct was left intact; in Group B, the ampulla of the contralateral oviduct was occluded; in Group C, contralateral total salpingectomy was performed. None of the rabbits in Group A conceived on the oophorectomized side. Seven of 19 animals became pregnant in Group B and 15 of 18 conceived in Group C. The results indicate that direct fimbrial-ovarian contact is not essential for ovum capture, and that ovum transmigration could contribute to fertility.