Effects of a novel three-dimensional grid intrauterine device on the uterus, steroid receptor and PAX2 of rhesus macaques

Intrauterine devices (IUDs) is the most effective methods of the reversible and long-acting contraception. 1) To develop a novel three-dimensional grid intrauterine device (3-DGIUD) with nickel-titanium (Ni-Ti) and silicone rubber. 2) To observe the effect of the 3-DGIUD on contraceptive efficacy and the change of uterus, endometrial sex steroid receptor, PAX2 in rhesus macaques (Macaca mulatta). The materials of the 3-DGIUD were the nitinol wire and the silicone rubber. The frame of the 3-DGIUD was three-dimensional and grid-like. Twenty adult female rhesus macaques were divided into the 3-DGIUD group (placing the 3-DGIUD, n=9), the sham operation group (no placing the 3-DGIUD, n=9) and the control group (n=2). On the 10th-day after surgery, the 3-DGIUD group and the sham operation group macaques were caged together with male macaques (female: male = 1:1). The uterus, 3-DGIUD and pregnancy of 18 female rhesus monkeys were examined by abdominal ultrasound every month. The endometrium pathological examination was carried out and the expression of PAX2 and hormone receptor (ER, PR) was detected by immunohistochemical staining. After 3-DGIUD was placed in case group for 3 and 12 months, only 1 of female macaque was pregnant in 9. The contraceptive effective rate was 88.9% (8/9). The 3-DGIUD in the uterus of macaques was observed by ultrasound. In the sham operation group, 9 macaques were pregnant (9/9). There was significant difference in uterine size of the 3-DGIUD group between pre-placement and after surgery for 3 and 12 months (P