Semen analysis as an indicator

What do we mean by fertility: male or female? Infertility whether it is male or female is usually defined as lack of conception leading to a live birth after 1 year of regular coitus. Humans are, however, relatively infertile at least in relation to fertility among the domesticated species. In the human, only one in four cycles will result in a clinical pregnancy and not all of these conceptions will result in the birth of a live child. Indeed, about one in every eight clinical pregnancies results in fetal loss at some stage during gestation. Such a poor outcome would not be acceptable to those involved in animal husbandry. The reason why the period of a year is used to define infertility is that at the end of 1 year a reduction in the frequency of conception among couples trying to achieve a pregnancy over that time will be seen. Moreover, after that interval an increase in the frequency of abnormalities in reproductive function can be found among couples that have been trying to conceive over that time period. The longer the inability to conceive persists, the less likely it is that natural conception will occur. Thus, the duration of the infertility has an important bearing upon its management. For example, for a couple that has been trying to conceive for 1 year the chances of natural conception in the subsequent year may be as high as 50% but after 5 years of trying to conceive, spontaneous conception will only occur in about 5% of these couples. This reduction in the percentage of natural conceptions indicates the presence of more serious and persisting faults in reproductive function. These data have some meaningful pointers in relation to the chances of spontaneous conception without the use of any form of medical aid. Time may thus play a role in the definition of infertility in men as well as in women. Age will also be an important factor in the determination of fertility. This is much more striking in women than it is in men and, indeed, it begins to play an important part when a woman reaches the age of 35 years. The definition of male infertility thus cannot be determined simply by the male partner, as the ability to conceive will be determined also by the female partner.