This study was designed to examine the teratogenic potential of copper releasing intrauterine contraceptive devices on the developing embryo. The tissues and organs of 11 whole embryos between 7 and 12 weeks of gestation were histologically examined for copper absorption after exposure to a copper intrauterine device in utero. The findings were not significantly different when compared with a control group of 7 embryos. No malformation or copper aggregates were observed in the various organs and placentas. The observations in this small sample would suggest that the copper-releasing intrauterine device has no deleterious effects on fetal development. The question remains whether malformations reported in some cases are associated with copper deposits in the tissues or with free copper ions in the fetal circulation. The implications are discussed.
PIP: The study was designed to examine the teratogenic potential of copper releasing intrauterine contraceptive devices IUD's on the developing embryo. the pregnancy rate with copper-bearing IUD's in situ has been reported as less than 5% per annum. 18 healthy fertile women aged 20-40 were studied. 11 conceived while using a copper-bearing IUD (Nova-T in 5 and Multiload in 6 cases); 7 women served as controls who conceived spontaneously with no previous history of using an IUD. Between 7 and 12 weeks of gestation an artificial abortion was induced in all 18 women. All 18 embryos were removed in toto, without injury. After fixation in neutral formalin the embedding process was carried out in paraffin and sectioning was performed, enabling examination of the brains, eyes, inner ear, heart and lungs, liver, pancreas, mesonephron, kidneys gonads vertebrae and limbs. All sections were stained for copper in accordance with Uzman's procedure. 2 mice were injected with a copper solution to verify the accuracy of the staining method. Maternal blood samples were taken on the day of the abortion and examined for plasma levels of copper and ceruloplasmin. The procedure of Dawson et al. was applied to determine the copper level and Richterich's for assessment of ceruloplasmin. The plasma levels of the copper and ceruloplasmin were within normal range, with no significant difference between the study and control groups (163.4+-41.4 va 137.8+- 37.0% mcg copper and 70.4+-14.9. vs 69+-19.9% mg ceruloplasmin). No organic malformations were found in either groups and the embryonic tissue was free of copper deposits. There was no structural impairment and no trace of copper deposits in the placentae when examined histologically however, traces of copper were found in the organs of mice. These results do not prove unequivocally that embryos exposed to copper contamination because of in site IUD are free of terato-genic risk, since the size of the study sample was small.