Sybil is clearly in stage one labor. her midwife knows this because it is characterized by

Sybil is clearly in stage one labor, her midwife is characterized by: The first stage begins when you start having contractions that cause progressive changes in your cervix and ends when your cervix is fully dilated. This stage is divided into two phases: Early labor: Your cervix gradually effaces (thins out) and dilates (opens). Active labor: Your cervix begins to dilate more rapidly, and contractions are longer, stronger, and closer together. People often refer to the last part of active labor as transition.

It’s because it’s was very fun