TY - JOUR T1 - Offspring sex ratio at birth in mountain climbers JF - Journal of Epidemiology and Community Health JO - J Epidemiol Community Health SP - 590 LP - 591 DO - 10.1136/jech.2008.078824 VL - 63 IS - 7 AU - M Saadat AU - M Khalili Y1 - 2009/07/01 UR - http://jech.bmj.com/content/63/7/590.2.abstract N2 - It has been reported that, within endurance-trained males, serum testosterone level significantly decreased as compared to their untrained age-matched counterparts.1 Also it has been reported that level of testosterone was associated with altitude.2 There is now abundant evidence that the offspring sex ratio at birth in mammals is partially dependent on the hormone levels of both parents around the time of conception.3 The offspring sex ratio at birth (SRB, the male proportion) of a sample of male runners varied significantly by their weekly training distance.4 Also, it has been reported that SRB was associated with altitude.5 Taken together, it is speculated that offspring SRB mountain … ER -