The administration of GnRH agonists for a period of three to six months prior to IVF or ICSI in women with endometriosis increases the odds of clinical pregnancy by fourfold. Data regarding adverse effects of this therapy on the mother or fetus are not available at present.
The impact of long-term gonadotropin-releasing hormone analogue treatment on preclinical abortions in patients with severe endometriosis undergoing in vitro fertilization-embryo transfer.
To examine the relationship between endometriosis and preclinical abortions and to evaluate the effect of gonadotropin-releasing hormone analogue (GnRH-a) therapy on these pregnancies.
                Of 67 women with severe endometriosis referred to us for in vitro fertilization-embryo transfer (IVF-ET), 32 underwent ovarian stimulation for oocyte retrieval with menotropins (protocol A), whereas the other 35 were admitted for the procedure after a 6-month period of hormonal suppression with a GnRH agonist (protocol B). The clinical impact of the preclinical and clinical pregnancies in both treatment protocols were evaluated on the basis of oocyte classification and embryo quality score.
                All patients were treated in our IVF Unit.
                Clinical pregnancy was used as our main outcome measure of success.
                A significantly higher number of preclinical pregnancies (P less than 0.0001) occurred in patients treated by protocol A. After GnRH-a treatment, the preclinical pregnancy rate declined significantly (P less than 0.0001), whereas the clinical pregnancy rate per cycle and per transfer rose significantly (P less than 0.0001 and P less than 0.0001, respectively). Furthermore, clinical pregnancies had a significantly better mean embryo quality score in comparison with preclinical pregnancies (P less than 0.0001).
                It is concluded that combining GnRH-a therapy before IVF-ET provides an improved treatment modality for preclinical abortions and infertility associated with severe endometriosis.