Since VEGF, which is a target for gonadotropins with LH activity in the ovaries of ovulating rats, is directly involved in the implementation of the angiogenic and proinflammatory effects that mediate ovulation, and, along with this, is responsible for the possible development of OHSS [31,32], we assessed the gene expression of two main isoforms of this factor, VEGF-A and VEGF-B, regulating VEGF-dependent cascades in the ovaries. This evidence concerns the gene VEGFB and ovarian hyperstimulation syndrome.