Primary Infertility Frequency

Primary infertility (failure of reproductive success) is relatively common in humans, and appears less common among the great apes. The causes in humans are many, including genetic disorders, environmental toxins, endocrine disrupters, sexually transmitted diseases, and disorders like endometriosis. Interestingly, endometriosis has not been reported in great apes (but it is common in monkeys), and sexually transmitted diseases in apes appear to be confined to viral infections. The four major bacterial STDs of humans are Chlamydia, N. gonorrhea, T. pallidum, and H. ducreyi which have never been described in wild apes.