The process of labor and delivery is divided into distinct stages, with the second stage dedicated to the final descent and birth of the baby. This phase begins once the cervix is fully dilated and involves the mother actively pushing to move the fetus through the birth canal. A defining point in this progression, which signals that birth is imminent, is a physiological event known as crowning. Understanding this milestone helps parents and medical teams prepare for the final moments of delivery.
The Definition of Crowning
Crowning refers to the specific moment during childbirth when the largest diameter of the baby’s head has passed through the pelvic outlet and remains visible at the external vaginal opening even between contractions. Initially, the baby’s head may be seen during a push, only to recede slightly when the contraction ends; this is known as “coming and going.” True crowning occurs when the head no longer slips back, establishing a firm presence at the vaginal opening.
Medical professionals confirm crowning when the fetal head is “firmly rimmed by the maternal vaginal wall.” This stage takes place during the second stage of labor, after the cervix has reached full dilation (typically 10 centimeters). Crowning visually confirms that the baby has successfully navigated the bony structures of the pelvis and is poised for delivery.
The Descent Sequence Leading to Crowning
The ability to crown is the result of a precise sequence of movements the baby must execute to pass through the mother’s pelvis. This journey is tracked using a measurement called “fetal station,” which describes the position of the baby’s presenting part relative to the mother’s ischial spines. The ischial spines are bony protrusions inside the pelvis, and their level is designated as station zero.
As the baby descends, the station number moves from negative values (above the spines) to positive values (below the spines). For example, a baby high in the pelvis might be at a -3 or -4 station, while the head is considered “engaged” when it reaches station zero. Before crowning, the baby must also perform an “internal rotation,” turning its head to align the widest part with the widest part of the pelvic outlet.
Crowning is associated with a fetal station of +3 or more, meaning the head has significantly dropped into the birth canal. This final descent indicates that the most challenging rotation and passage through the pelvic bones have been completed.
Managing the Delivery at the Point of Crowning
When crowning occurs, the mother experiences a distinct sensation in the vaginal and perineal area, commonly referred to as the “ring of fire.” This intense stinging or burning feeling is caused by the extreme stretching and thinning of the perineal tissues as they accommodate the diameter of the baby’s head. Although painful, this sensation signals that the baby is only moments away from being born.
At this juncture, care providers typically guide the mother to stop active, forceful pushing to avoid rapid expulsion of the head. Instead, they encourage controlled breathing techniques, such as “pant and blow,” which allow the baby’s head to deliver slowly and gently. This controlled delivery allows the perineum (the tissue between the vagina and the rectum) time to stretch gradually.
Slowing the process helps minimize the risk of severe perineal tearing. Once the tissue has stretched fully, the nerves in the area can become temporarily blocked, leading to a sensation of numbness that replaces the burning. The medical team may also apply warm compresses or manual support to the perineum to aid in the controlled delivery of the head.