The number of conceptuses occurring after placement of an IUD in the right uterine horn of twenty golden hamsters was compared to the number present in ten hamsters subjected to sham operation on Days 7, 12 and 16 of gestation. A unilaterally placed IUD prevented pregnancy in the containing horn, but exerted no significant effect upon implantation sites in the contralateral horn. Sham operations did not prevent implantation.
Histological examination revealed inflammatory reaction only in those uteri containing a silk suture. No communication between uterine lumina could be demonstrated.
The presence of an IUD did not alter the oestrous cycles of hamsters.