Oxidative Stress and its Role in Female Infertility and Assisted Reproduction: Clinical Implications
Reactive oxygen species (ROS) are involved in physiological functions and act as mediators in various signaling processes. Elevated or sustained generation of free radicals and non radical species derived from free radicals can lead to an imbalance in the intracellular redox homeostasis. Normally, any excess levels of reactive radical and nonradical species generated are intercepted by antioxidants. An excess of the free radicals however, can precipitate pathologies in the female reproductive tract. Oxidative stress (OS) is involved in various pathological conditions such as abortions, preeclampsia, hydatidiform mole, fetal teratogenecity, preterm labor and intrauterine growth retardation, all of which lead to an immense burden of maternal and fetal, morbidity and mortality. In addition evidence suggests that oxidative stress plays a role in the proinflammatory changes seen with polycystic ovarian disease and also in the pathogenesis of endometriosis and tubal factor infertility. Our review captures the role of OS in assisted reproduction specifically in in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) and in vitro maturation of oocytes (IVM). We also examine the role antioxidants play in modifying the fertility outcomes with assisted reproductive techniques. Finally in vivo and in vitro strategies to modulate the influence of ROS and establish an optimal redox state are also discussed.