Clinical application of scanning electron microscopy in human reproduction

The state of the art of scanning electron microscopy in the field of human reproduction and the clinical significance of SEM techniques is described on the basis of 272 articles in which the SEM was a substantial instrument for research. The first section deals with reproductive cell biology, the various cell types and function in relation to cell surface microstructure. The second section outlines briefly various types of cell and tissue preparation, and advantages and pitfalls. The following sections describe the female reproductive system (including vulva, vaginal and ectocervical squamous epithelium, metaplastic epithelium of the transformation zone, endocervix and cervical mucus, endometrium, IUDs, tube, ovary, and mammary gland), the male reproductive system (male sex organs, spermatozoa) and the conceptus (placenta, embryogenesis). It is indicated where SEM has revealed deeper insights in the structure and function of reproductive cells and tissues and where SEM has a potential for clinical application. The following areas seem promising: the placenta (description of various classes of pathological conditions), the oviduct (description of two types of hydrosalpinges with different prognostic significance), cervical and ascites cytology (SEM's capacity for (early) discrimination of malignant cells) and spermatozoa (prognostic significance of classification with the use of X-ray micro-analysis). In many instances the same results can be obtained by routine LM and TEM. Because SEM does have potentially large diagnostic and prognostic powers further research is essential in order to establish the future role of SEM in the field of human reproduction.