The success rates of IUI and IVF, even if donor sperm is used, rely on factors such as age, endometrial thickness and pattern, what is causing infertility and for how long, and the protocol and medications for ovarian stimulation.
In order for the specialist to find out what is leading to failure, every step taken during the process should be examined. If necessary, if the patient's response to medications was insufficient or inappropriate, the solution may be to just change the stimulation protocol or the meds to take to see whether the results change.
Moving on to another method is another option. For instance, if success has not been achieved after 3-4 attempts with IUI, patients are often recommended to give IVF with own eggs a try. If a successful pregnancy does not occur, moving to donor eggs could give you the chance to become parents.
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