Clinically and experimentally male fetuses are at significantly greater risk of dying or suffering injury at birth, particularly after premature delivery. We undertook a retrospective cohort analysis of 60 female and 65 male singleton preterm fetal sheep (103-104 days, 0.7 gestation) with mean arterial blood pressure (MAP), heart rate, carotid and femoral blood flow recordings during 25 minutes of umbilical cord occlusion in utero. Occlusions were stopped early if fetal MAP fell below 8 mmHg or if there was asystole for >20 sec. Fetuses that were able to complete the full 25 minute period of occlusion showed no differences between genders for any cardiovascular responses. Similar numbers of occlusions were stopped early in males (mean 21 min, n=16) and females (mean 23 min, n=16), however, they showed different responses. Short-occlusion-males (n=16) showed a slower initial fall in femoral vascular conductance, followed by greater bradycardia, hypotension, and associated organ hypoperfusion compared with full-occlusion fetuses. In contrast, short-occlusion female fetuses (n=16) showed a significantly more rapid early increase in femoral vascular conductance than the full-occlusion fetuses, followed by worsening of bradycardia and hypotension that was intermediate to the full-occlusion-fetuses and short-occlusion-males. Amongst all fetuses, MAP at 15 minutes of occlusion, corresponding with the time of the maximal rate of fall, was correlated with post-mortem weight in males (r²=0.07) but not females. In conclusion, male and female fetuses showed remarkably similar chemoreflex and hemodynamic responses to severe asphyxia, but some males did show impaired hemodynamic adaptation within the normal weight range.