The question of endometriosis surgery prior to IVF is a somewhat controversial area of reproductive medicine. Most reproductive endocrinologists do not recommend surgery prior to IVF unless the woman has advanced endometriosis, in particular, an ovarian endometrioma.
IVF is associated with excellent pregnancy rates (even without surgery) in women who have only mild to moderate endometriosis. When advanced endometriosis is present, such as an ovarian endometrioma, its surgical removal prior to IVF may enhance the chances for a successful IVF outcome and may decrease infectious complications related to egg collection. Thus, in such cases, most reproductive endocrinologists recommend the removal of advanced endometriosis prior to treatment using IVF.
However, severe endometriosis with endometriomas may lead to diminished ovarian responsiveness, and ovarian surgery may further compromise a patient's response to fertility drugs in such cases. So the decision to perform extensive surgery for endometriosis must be weighed against the potential impact of that surgery on the ovary.
Also, advanced endometriosis may increase the likelihood for an early pregnancy loss or spontaneous abortion. By first removing the endometriosis, the outcome of pregnancy may be improved. Ultimately, the decision whether or not to perform surgery rests between doctor and patient. In general, we believe that the removal of a small 1–2 cm endometrioma is unlikely to impact IVF success, but the removal of large endometriomas may be reasonable before attempting IVF. Some doctors advocate a threshold of 4 cm for endometrioma removal, but the data supporting this contention warrant further study.