EMBRYOTOXICITY AS A MARKER FOR RECURRENT PREGNANCY LOSS

Some cases of unexplained recurrent pregnancy loss may be due to embry otoxic factors present in the mother's serum. In vitro assays have bee n devised to study the effect of these factors on pre-implantation, pe ri-implantation, and somite stage rodent embryos. Embryotoxic activity has been found in a high percentage of recurrent aborters but is also present in women with endometriosis and unexplained infertility, sugg esting that there may be a range of factors acting at different stages of development. Embryotoxic activity may be predictive of pregnancy o utcome and has been shown to be decreased after hormone and immunother apy. However, its true value can only be assessed when the nature of t he toxic factors is understood. Preliminary characterisation studies s uggest that toxic activity may due to both immunological (antibodies o r cytokines) and nutritional factors.