<prompt> Second stage of labor stas from: March 2013Rupture of membranes35 dilatation of cervixFull dilatation of cervixCrowning of head  <response>: Ans. C i.e. Full dilatation of cervix Stages of labor 1st stage: Onset of labor to dilatation of cervix - 6-20 hours in primigravida - 2-10 hours in multigravida 2nd stage: From full dilatation of cervix to complete bih of baby 3rd stage: Bih of infant to delivery of placenta 