Effect of a novel copper-containing intrauterine device material on the endometrial environment in rabbits.

OBJECTIVE(S): This study aimed to determine whether intrauterine placement of a novel composite material [copper (Cu) microparticles, low-density polyethylene, and methyl vinyl silicone rubber (Cu/LDPE/MVQ)] could prevent pregnancy in rabbits, and to evaluate the effects of Cu/LDPE/MVQ on the endometrial environment.

STUDY DESIGN: Eighty sexually mature female rabbits were randomly divided into four groups (n=20 each group): control (sham-operated), LDPE/MVQ, Cu/LDPE/MVQ microcomposite, and bare Cu. Ten rabbits from each implant-bearing group were randomly selected for a mating experiment beginning 30 days after insertion. Pregnancy outcomes were observed 15 days after mating. Factors associated with endometrial bleeding and inflammation in the remaining rabbits in each group, and the surface conditions of the implants, were investigated 90 days post-insertion.

RESULTS: The Cu (0 embryo) and Cu/LDPE/MVQ (0 embryo) groups had significantly fewer embryos than the LDPE/MVQ (1.0±0.6 embryos, p<.05) and sham-operated groups (4.1±1.3 embryos, p<.05). Compared with bare Cu, the Cu/LDPE/MVQ composite material was associated with considerable reductions in injuries and factors associated with abnormal endometrial bleeding and inflammation, such as matrix metalloproteinase 9 (MMP9) and prostaglandin E2 (PGE2 ). Additionally, the surface of implanted Cu/LDPE/MVQ remained much smoother than that of implanted bare Cu.

CONCLUSION(S): This novel Cu-containing intrauterine device material exhibits a similar effect in prevention of pregnancy with bare copper, and lower levels of inflammatory markers.

IMPLICATIONS: This study demonstrates the potential of the novel Cu/LDPE/MVQ microcomposite material as a future substitute for conventional intrauterine device materials.