The reproductive toxicity of rat models implanted with copper-bearing intrauterine device at teratogenic sensitive period by continuous extraction method / 中国组织工程研究

ABSTRACT

BACKGROUND:At present, the copper-bearing intrauterine device, a kind of class III medical devices, is commonly used in China. However, there is no clear conclusion about whether it has impact on the embryo or fetus in some cases, such as unexpected pregnancy during long-term implantation and pregnancy in a short time after removing it. OBJECTIVE: To evaluate the safety of copper-bearing intrauterine device by observing the influence of copper-bearing intrauterine device extracts on pregnant rats and rat fetuses by tail vein injection in the sensitive period of teratogenesis. METHODS: A total of 60 fertilized rats were divided into control group, high dosage group, middle dosage group, and low dosage group. The copper-bearing intrauterine device extracts were prepared by the continuous extraction method. Different concentrations (0.2, 0.1, 0.05 g/mL) of copper-bearing intrauterine device extracts were injected by the tail vein at the 1st day of pregnancy in the latter three groups at a dosage of 0.01 mL/g per day. The control group was given the same amount of normal saline. The injection lasted for 20 days. Then, the pregnant rats were sacrificed to measure body mass, check both sides of the uterus and internal organs, isolate fetal rats, as wel as record the quality of uterus and fetal rats, corpus luteum, implantation numbers, the number of stilbirths, then number of live births and the number of fetal absorption. The fetal rats were determined in the folowing aspects body mass, body height, tail length, the ossification degree and appearance of the occipital bone, bone and visceral anomalies. RESULTS AND CONCLUSION: The number of births, implantation numbers, the number of live births, the number of corpus luteum, the percentages of live births and stilbirths, the number of resorbed fetuses, and the weight of uterus and fetal rats in the control group showed no difference from those in the other three groups (P > 0.05). No malformation in the internal organs occurred. Compared with the control group, the high, middle and low dosage groups showed no difference in the height, tail length, body mass, and ossification degree of the occipital bone of fetal rats (P > 0.05). No malformation in the appearance, skeleton and internal organs occurred in the fetal rats. These findings indicate that there were no maternal toxicity, abnormal embryonic growth or rat fetus anomalies after injecting copper-bearing intrauterine device extracts into pregnant rats in sensitive period of teratogenesis.