Ultrastructural studies on the endometrium of women wearing TCu-200 intrauterine devices by means of transmission and scanning electron microscopy and x-ray dispersive analysis.

Endometrial biopsies obtained from 12 young women wearing TCu-200 intrauterine contraceptive devices from six to 12 months were studied by means of transmission and scanning electron microscopes as well as with the use of rubeanic acid stains and x-ray dispersive analysis. Six biopsies were taken at Day 10 and six were taken at Day 20 of the menstrual cycle. The aim was to investigate epithelial and stromal changes possibly related to copper deposition. The main changes were located in the cell organelles at Day 10 of the cycle. The mitochondria disclosed vacuolization of the matrix and myelin figure formation in 70 to 80% of the epithelial cells. There were also increased numbers of lysosomes. There were similar alterations of secretory endometrium in only a few cases. Instead, there was an increased number of mitochondria, and most of them were dividing. Rubeanic acid stains as well as energy-dispersive x-ray analysis failed to reveal significant amounts of copper in the various cell organelles studied. The above observations seem to indicate that there is a definite alteration of the mitochondria of epithelial cells which may result in impairment of respiratory mechanisms and energy production, rendering the endometrial environment inhospitable to the fertilized egg. These changes are thought to be reversible. The absence of copper is explained on the basis of a rapid turnover of the endometrium or to a problem in sampling common to this methodology.