Sperm treatment with extracellular ATP increases fertilization rates in in-vitro fertilization for male factor infertility

Abstract

Previous work from our laboratory has revealed that extracellular ATP is a rapid and potent activator of human sperm acrosome reaction and fertilizing ability. In the present study, we assessed the effects of in-vitro sperm incubation with ATP on fertilization and embryo development in couples undergoing in-vitro fertilization (IVF) for male factor infertility. Oocytes from 22 women undergoing ovulation induction were divided in two groups and inseminated in vitro either with selected spermatozoa from the corresponding partner suffering from male factor infertility pre-incubated with ATP (2.5 mM) for 1 h, or with spermatozoa incubated with 0.9% NaCl solution (control group). After insemination, fertilization was assessed by the presence of pronuclei and then by embryo cleavage. The fertilization rate in the group of oocytes inseminated with ATP-treated spermatozoa improved significantly with respect to the control group (65.7 versus 42.5%, P < 0.01). No significant differences were observed in embryo cleavage and embryo quality. Embryos from both treated and control groups were transferred together in 20 transfer procedures, and in two couples fertilization was not obtained. Nine pregnancies occurred: one biochemical, one miscarriage, and seven patients delivered 9 healthy babies. Two pregnancies were twin with an overall pregnancy rate of 40.9% per cycle and of 45% per transfer. In conclusion, the results of the present study demonstrate that, in humans, extracellular ATP induces a significant increase of sperm fertilizing potential, as these findings are a rationale for the use of ATP for in-vitro treatment of human spermatozoa during IVF.

Pathophysiology and Therapeutic Potential of Purinergic Signaling

“…In humans, ATP induces a significant increase in sperm fertilizing potential and this provides a rationale for the use of ATP for treatment of spermatozoa during in vitro fertilization (Rossato et al, 1999). Knockout mice lacking P2X 1 receptors appear normal, but fail to 74 BURNSTOCK breed, and this is associated with loss of the purinergic component of sympathetic cotransmission in the vas deferens; these findings raise the possibility of developing nonhormonal ways of regulating male fertility (Dunn, 2000).…”

Purinergic signalling in the reproductive system in health and disease

“…In humans, extracellular ATP induces significant increase of sperm fertilising potential and the use of ATP for in vitro treatment of spermatozoa during in vitro fertilisation (IVF) for male factor infertility was proposed [350]. Preincubation of fresh spermatozoa with adenosine before the transient co-incubation IVF can also improve the monospermy rate in pigs [137].…”

Purinergic Signalling: Pathophysiology and Therapeutic Potential

“…[70][71][72] Treatment of sperm with extracellular ATP improves the in vitro fertility rate for IVF. 73,74 …”