A soluble dimeric immunoadhesin includes a dimerized first polypeptide chain and a dimerized second polypeptide chain. The first polypeptide chain has a general formula of Z1-Z2, and the second polypeptide chain has a general formula of Y1-Y2. Z1 is (i) an extracellular domain of a first cell surface receptor or a functional variant or fragment thereof, or (ii) a first cytokine or a functional variant or fragment thereof; Z2 is a dimerization domain of an immunoglobulin constant region or a functional variant or fragment thereof. Y1 is an extracellular domain of a second cell surface receptor or a functional variant or fragment thereof, or (ii) a second cytokine or a functional variant or fragment thereof. Y2 is a dimerization domain of an immunoglobulin constant region or a functional variant or fragment thereof. A dimeric protein can be used for the treatment and prevention of infertility-related diseases.