Raghuveer Choudhary, Chawala Vk, Soni Nd, Jayant Kumar, Vyas Rk.
Oxidative stress and role of antioxidants in male infertility.
Pak J Physiol Jan ;6(2):54-9.

With regular cohabitation without any protection if women do not conceive for at least a period of one year is labelled as infertility. It is based on the observation that most of the normal couples achieve conception within a year of initiation of regular sex.1 Infertility affects approximately 15% of all couples trying to conceive. It’s a major clinical problem, affecting people medically and psychologically. Male factor infertility is the major cause in roughly half of the cases, and no identifiable cause can be found in over 25% of infertile males.2

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