A. Cervical dilation is the actually opening of the cervix. A women must get to ten centimeters to be completely dilated.
Effacement is the thinning of the cervix.
Effacement and dilation go together, not on over the other. However, just becaues she is dilating and effacing doesn't mean that labor will begin within the hour, or the day, or even the week. Nor does it mean that the woman who is not effaced or dilated will be pregnant for another week as some would have you believe. I've even had students walk around at five cetimeters for about 2 weeks. ACCE, has been a childbirth educator and breastfeeding counselor for over 18 years.