Sri Aurobindo
Letters of Sri Aurobindo
Volume IV - Part 3
What seems to be best is that the movement of rising above should be completed and if you can feel there the wideness, peace, calm, silence of the Self and that can come down into the body through all the centres and there can be the working of the Force in that condition of the physical being, then the vital-physical difficulty can be faced. The effort to do it by personal tapasya can carry one to a certain point, it can throw out sex etc., 
but for most it does not prevent all coming back by attack – unless the force of tapasya is so great and continuous that these forces get no chance. But the elimination of these things can only come, I think, by the descent of the higher consciousness – bringing with it the self-existent calm and wideness, the higher force and the Ananda occupying all down to the cells of the body. It is quite certain that these three together in the body can leave no room for sex – even if sex came, it would at once get so transmuted that it would be sex no longer.