Cervical Dilatation

What is Cervical Dilatation?

Cervical dilatation is a process which occurs during labor and is essential for a safe delivery. During cervical dilatation, the cervix gradually opens and expands to let the baby pass through the birth canal.

Cervical dilatation begins on its own during the first stage of labor. The cervix stretches and grows thicker as contractions become longer and stronger. It typically takes 8-10 hours for the cervix to open to 10 centimeters, the widest point needed for a safe delivery.

What Factors Affect Cervical Dilatation?

A number of factors can influence the effectiveness of cervical dilatation:

  • The size of the expecting mother’s pelvis.
  • The position of the baby.
  • The shape of the mother's cervix.
  • The amount of oxytocin released during labor.
  • The strength of the mother's contractions.

The size and shape of the mother's pelvis is determined primarily by genetics. In some cases, pelvic size and shape could be determined through routine ultrasound before the baby is born.

The position of the baby during labor can be assessed through an internal pelvic exam. This may determine the effectiveness of cervical dilatation.

How is Cervical Dilatation Monitored?

Cervical dilatation is usually monitored through vaginal exams conducted during labor. During the internal exam, a health care provider will measure the size of the cervix using a flexible instrument called a dilator.

The measurements can be documented, allowing health care providers to track the progress of labor and determine how long it might take for the cervix to completely dilate. If the cervix is not progressing as it should, the health care provider may recommend interventions to accelerate the process.