The role of Natural Cycle IVF in assisted reproduction.

Natural Cycle IVF (NC-IVF) with and without modifications is being increasingly performed. NC-IVF and conventional gonadotropin-stimulated IVF (cIVF) should not be understood as competing treatments, but as complementary treatments with different target groups and to some extent other indications. NC-IVF is particularly interesting for couples who wish to save money, wish a treatment with as few risks as possible and for women who would like to avoid selection and cryopreservation of embryos. NC-IVF therefore contributes to the concept of individualized and patient-oriented therapy. The time to pregnancy is slightly longer than with conventional IVF. NC-IVF is particularly suitable for younger women and for women with a very low ovarian reserve. In this article, the principles of NC-IVF, i.e. monofollicular IVF without gonadotropin stimulation, are described and the technical differences to cIVF, advantages and disadvantages, perinatal outcome and indications for NC-IVF are highlightened.