Anatomy General obstetrics e348b206 During the active phase of labor the minimum effective dilatation of cervix in primigravida should be at the rate of A 0.5 cm/hr B 1cm/hr C 1.5 cm/hr D 2 cm/ hr High-Yield Explanation Effective dilatation of cervix in a primigravida during active phase of labor is 1cm/hr