P-492: Massive multipronucleated fertilization after ICSI in patients with Reynaud′s Syndrome

Abstract

The presence of multipronuclear oocytes after an IVF treatment is a multifactorial phenomenon involving the competence of both male and female gametes. ICSI has been reported to prevent the development of multipronuclear oocytes when polyspermia is thought to be the cause of multipronuclearity. Primary Reynaud′s Syndrome is a vasculopathy which was reported to be associated with infertility and poor obstetric outcome though its mechanism is still unexplained. There is no description about its perfomance in assisted reproductive techniques. We report here the ocurrence of massive multipronucleated fertilization after ICSI in two female patients suffering Reynaud′s Syndrome. Retrospective analysis. Both female patients had a diagnosis of unexplained infertility and Primary Reynaud′s Syndrome upheld by clinical and laboratory findings, with male partners being normal. Ovulation induction included the use of recombinant gonadotropins and GnRH agonists. Patient A (34 years old) underwent during 2005 an ICSI procedure after a failed IVF attempt in 2003 where 8 out of ten metaphase II oocytes had shown multipronucleation (3, 4, 6 and 7 pronuclei respectively). Patient B (32 years old) had ten metaphase II oocytes that were divided half to conventional IVF and the other half to ICSI in order to test his fertility performance and at the same time to bypass any potential hidden male factor responsible for the unexplained infertility. Four mature oocytes were retrieved from Patient A that showed 5, 7, 9 and 9 pronuclei respectively 17 hours post injection. Patient B had 10 metaphase II out of 16 oocytes retrieved. The above mentioned five oocytes inseminated by IVF showed 6, 5, 4, 4 and 3 pronuclei respectively. The other 5 oocytes injected by ICSI showed 6, 6, 3 and 0 pronuclei respectively. This is the first report that call the attention about a possible mechanism of infertility in Primary Reynaud′s Syndrome. Although ICSI can be an useful tool to prevent the appearance of multipronuclear eggs, it may not operate as an adequate technique when the ethiology is other than a failure in the mechanism to block polyspermia. Rawe (2000) reported that 21.5 % of the cases of abnormal fertilization after ICSI were due to defects in pronuclei formation ascribed to processes of diginy, diandry or subnucleation. Reference: Rawe, V. (2000). Cellular events during fertilization in humans. Dissertation submitted to obtain the PhD degree in Biological Sciences. School of Natural Sciences of The University of Buenos Aires.