Novel use of laser to assist ICSI for patients with fragile oocytes: a case report

Abstract

An inadvertent consequence of intracytoplasmic sperm injection (ICSI) is the degeneration of some of the microinjected oocytes. Most patients may not suffer any disadvantage through losing oocyte(s) during micromanipulation; however, in some circumstances, this can result in a reduction of the chances for pregnancy. This study reports a clinical pregnancy obtained by a novel approach using laser-assisted micro-opening of the zona pellucida prior to ICSI to secure a non-traumatic micro-injection that avoids degeneration of oocytes. A total of 12 oocytes were obtained from the 36 year old patient in her third IVF treatment cycle, following two previously failed attempts where very high degeneration rates of oocytes after ICSI were recorded, together with suboptimal embryo quality. Five of the 11 matured (MII) oocytes were submitted to conventional ICSI and the other six MII oocytes first underwent laser-assisted opening of the zona pellucida (5–7 μm hole size was created with a 1.48 μm diode laser) before microinjection (LA-ICSI). Three of the five conventionally microinjected oocytes degenerated while one oocyte fertilized normally and developed to a good quality embryo. After the LA-ICSI procedure, one of the six oocytes degenerated and four oocytes fertilized normally; of these, two developed to excellent quality embryos, one to a good quality embryo and one to a poor quality embryo. The three best embryos (LA-ICSI group) were transferred to the patient on day 3. Rising serum human chorionic gonadotrophin concentrations were measured 12 days after transfer and on week 7 two implantation sites were detected, together with regular heart activity. The results of the present report suggest that laser-assisted ICSI may provide a safer approach to non-traumatic microinjection of oocytes than conventional ICSI, thereby minimizing the risk of degeneration and possibly also improving embryo quality. Therefore, it is suggested that laser-assisted ICSI might be applied in all cases associated with difficult zona pellucida penetration or/and fragile oolemma, or where patients have very few oocytes available, to improve the chances for pregnancy.