The allure of a sauna is not something you just think about, but rather, you feel it, you live it. It’s an ecstatic experience, so much for the loose talks and other wild escapades men like finding in such "dingy places”.But not all those who frequent saunas are into the filial bliss, for, as nature dictates today, men are increasingly finding themselves in day-long office work, with hardly any time left to exercise and keep their bodies in shape. The mirror becomes simple: John is a 30-year-old man with a good job in a telecom company. The good job has also come with a lavish lifestyle, which has since transformed the hitherto pencil thin engineer into a flabby sturdy fellow.  His weight has become a health concern. Desperate to check his weight, he has tried all remedies including frequent visits to saunas around Kigali.  But this has not helped John cut weight. Instead, his worries have increased; from being overweight. His habitual visit to the sauna could only make his worries worse as medical experts warn that regular use of sauna causes infertility in men.A study released recently indicate that men are likely to become infertile if they over use the sauna. According to, Dr Xu Deyi, of Chinese Society of Obstetrics, in his study released last month, says about 70 per cent of men who use saunas twice a week, are prone to infertility due to the high temperatures their private parts are exposed to in saunas. Saunas are increasingly becoming a life style trend in Rwanda mainly in the city centres and majority of the users are middle age working class people.  Dr Janvier Rwamwejo, of King Faisal Hospital, Rwanda, warns that cases of men being diagnosed with infertility are on the increase. "More men in Rwanda are increasingly being diagnosed with infertility related issues,” Rwamwejo said. Although the major cause is not known, experts believe saunas could be among the major causes of this trend. "Anything that increases heat or pressure in the male private parts affects their sperm production,” Rwamwejo said.To some users, warning bells have started ringing.  "I have lived with my fiancé for the last one-and-a-half year. Even without using any family planning method, she is yet to conceive! Could I have a problem because I have used the sauna for the last three years?” wonders Simon, a regular user of a sauna in Remera. Is it just a trendy life style? Many men and women go to the sauna after work for various reasons, including losing weight. To many it is a life style that is catching up as the city modernises. Jane, a masseuse at a Kigali based massage and Sauna palour says she receives between 15-80 clients daily. One pays between Rwf2,000 and Rwf10,000 for sauna services, depending on the location. Most clients comprise the corporate class.  Before getting into the small hot room where one sweats profusely, one is required to strip naked and wrap a small-sized cloth around the waist. A sauna is an unpainted, wood-paneled room with wooden platforms and a constant heater. The sauna emits dry air at a high temperature of over 80°C.  Worry of never getting children Dr Xu, in his findings, said that men who spend much time in a sauna are prone to dead sperm, weak sperm and other illnesses, which cause infertility. Dr James Kamugisha, a private medical practitioner, echoes the same worry. "I thought its common sense to everybody that too much heat affects the male reproductive functioning. Maybe that could be complicated for the common person to determine but they know what too much sunshine can do to a body, cancer, headaches and so forth. And this is just natural heat; now imagine the dangers accumulated by steam from an artificial source like a sauna,” said Dr Kamugisha. Medical experts say while the normal body temperature is 37°C, the scrotum needs between 35.5°C and 36°C to operate normally. However, experts explain that the testicles’ temperature could rise if the scrotum is squeezed on the body for a long time, for instance, due to tight pants or by exposing them to excessive heat such as in saunas and steam baths. "The temperature in saunas can rise to over 45°C, which is dangerous to the scrotum, and if a sauna becomes a part of your lifestyle, it means that slowly, you are switching off performance of your manhood,” explains the expert.  "A man needs one sperm to fertilise an egg, but if he lacks 20 million sperms per one millilitre, he will find problems impregnating a woman because the sperm count would be low,” he said. Besides lowering sperm production, experts say excessive heat can also weaken the sperms. This hinders their ability to swim in the fallopian tubes to fertilise an egg. "Some men tend to think that ejaculating alone is enough to cause pregnancy. But fertilisation does not occur at that exact point of the woman’s private parts where a man ejaculates. The sperms must swim through the fallopian tubes to meet the eggs,” he said."Imagine a situation where the sperms are few and weak! This means they cannot fertilise the female egg. So, you may ejaculate whenever you have sex, but no conception will take place.”  Abnormal sperms such as those without tails, or with large, small, tapered or crooked heads, and sperms with curled or double tails are less likely to swim through the fallopian tubes to fertilise an egg.