By Avinash Prabhakar New Delhi, July 3 : The infertility and the impaired fecundity have been a concern through ages and is rising for various reasons. The prevalence of infertility in the general population is 15 to 20 per cent, as per the Word Health Organisation and the male infertility factor contributes around 40 per cent to this rate. Talking about the rising male infertility, Dr Neeta Singh, Professor, Department of Obstetrics & Gynaecology,, said that Sperm DNA fragmentation is an important factor for this. "The parenting age has considerably increased compared to last 25-30 years because of late marriage trends. Now, males generally marry after 30-33 years and more or less, there is same pattern for females also. So, with the advancement of the ages, there happens DNA fragmentation in the sperm which is primarily responsible for the male infertility," said Dr Singh. Among other reasons, the rising temperature is also an important factor for the male infertility, she said, adding that, "Our clothing patterns have also an impact on the infertility." "The testes are naturally placed outside the body because it even can not tolerate the body's normal temperature. But, tight dressing trends and hot geographical location causes severe infertility," said Dr Singh of AIIMS, adding that it also affects the blood circulation of the body. She continued saying that the tight dressing is for the nations like US where temperature is normally cold, but in Indian context, it may be fatal. The effects of elevated testicular temperature may result in abnormal spermatogenesis and impaired sperm morphology and function, she said, while adding that "our ancestors used to wear loose and airy dresses like 'dhoti' and 'lungi'". Prolonged heat can create a problem on that part, she said, adding that it is advisable to wash the male part with cold water after several intervals if exposed to high temperature. She also underlined the late night working culture as prime factor for infertility because it affects the secretion of Melatonin hormone that is produced by brain in response to darkness. "There is a trend of declining sperm count across the globe and accordingly, the WHO has also reduced the acceptable value for normal sperm count. From 45 million sperm count, it has been reduced to 15 million sperm count which is supposed enough for pregnancy", said Delhi-based fertility expert Dr Archana Dhawan Bajaj. "In the semen analysis, good count was considered above 60 million a decade ago, but in today's environment, we find maximum normal sperm count around 30 to 40 million and it has considerably decreased," she added. Dr Bajaj said that around 40 per cent of total infertility is caused by male infertility, adding that if sperm count is above 15 million, pregnancy can be achieved. "The internal rhythm of the body has been broken due to work pressure of global lifestyle. People living in India work as per the timing of European countries or other nations which adversely affect the rhythm of the body and results into the performance pressure affecting their sperm quality", added Dr Bajaj. Meanwhile, India's Total Fertility Rate (TFR) is currently below the replacement level of fertility of 2.1 children per woman. The TFR is the average number of children born to a woman in her lifetime. The below-replacement fertility results eventually in negative population growth and extinction of the population in the long term. (Avinash Prabhakar can be reached at avinash.p@ians.in) /IANS