Crowning stage of birth

©David B. Fankhauser, Ph.D.,
Professor of Biology and Chemistry
University of Cincinnati Clermont College,
Batavia OH 45103

The arm is born
Crowning is when the top of the infants head is first observed
File "Birth_Videos.htm" was last modified on 29 May 2008.
This page has been accessed Counter times since 3 June 2009. 
3 June 2009
Once the arm is born,
the whole infant usually slips right out.

Labor consists of three stages:  Dilation of the cervix (by far the longest portion), delivery of the infant, and delivery of the placenta.
Here is a cartoon explanation of the stages (ads at beginning and end...)

The opening of the cervix (the cervical os) is tightly closed and sealed during pregnancy.  The initial stage of labor opens (dilates) the cervix until it is large enough for the fetus' head (the largest presenting part) to pass through, usually 10 centimeters or "four fingers".  The first sign of dilation is the discharge of the mucus plug from the cervical os, termed the "show."  It is often tinged with blood.  Contractions will usually be noticed at this time.
The safe manner to determine the stage of dilation is with rectal palpation with a gloved hand.  Dilation of the cervix takes 10-20 hours.  Dilation is aided by the fetus' skull wedging it open, hence the 'conehead' appearance of occipitally born infants. 

Here is a Cartoon of the first two stages of labor. 

The urge to push should be resisted during this first stage so that the cervix is not torn.  The amniotic membrane may break releasing the amniotic fluid ("the waters") during this time.  It is best if they break just before the next stage of labor so that they act as a lubricant.

Once the cervix is fully dilated, the fetus begins to move down the birth canal, again, using its 'pointy little head' as a wedge.  This process usually takes 1 to 2 hours.  The perineum membrane which surrounds the opening of the vagina needs to be fgiven time to dilate to prevent tearing.  Massage will help.
Here is a cartoon diagraming the stations of presentation (progress of the fetus through the birth canal).

A 51 second video of a normal occipital presentation birth. ("Push, push, push...") I do not recommend immediate clamping and cutting of umbilicus.  Fetal blood in the placenta is lost to the baby.
Five minute video with cartoon explanation.  Includes delivery of placenta ("afterbirth").
A 10 second easy birth
A VERY vocal mother without anaesthesia, but rapid birth.
Video of birth with vocal mother. Massage perineum (0:20- 1:00), head born 1:10)(crowning not shown)
Delivery in back seat of a car (shows waters breaking explosively at 0:14) (arm out at 0:36)(from 1950s?)

Many delivery rooms perform an episiotomy which cuts the perineum to enlarge the opening.  Contractions become powerful:

Strong contraction reaction (1:40), mirror shows crowning (5:32), delivery (5:56), placenta (7:20)

The sign of imminent birth is the appearance of the top of the fetus' head, termed "crowning."  The head will retract and appear a number of times, each time showing more of the head. 

German: Squatting, good view of crowning, head etc (at 5:20-3:47) placenta (5:20)

Begins with crowning, but infant delivery (1:05) partly obscured

The most challenging stage of the birth is the delivery of the head because it is the largest presenting part.  Once the head in born, the most strenuous part of labor is over.
Good view of head (and hand) being born

After the head is born, a few more contractions will cause a shoulder to appear, and arm to flip out, and get ready to catch because the body and legs are easily delivered compared to the head and shoulders.

Rapid delivery of head and body.

After the infant is delivered, it should be placed at the mother's breast.  The umbilicus should not be cut until the blood has drained from the placenta into the infant.  The stimulation of the infant at breast will trigger the release of oxytocin from the posterior pituitary.  This will strengthen uterine contractions, assisting with moving blood out of the placenta, and the expulsion of the placenta:

The placenta should be closely examined to ensure that it is entire, and that no fragments remain in the uterus where they could cause bleeding and infection.

Examination of the placenta, the umbilicus and the membranes

Here is the Apgar scale to evaluate newborns.  They should be 7 or above by 10 minutes after birth:
Apgar table


Here is an explicit (and sometimes humerous) video from the Discovery Channel discussing the components of the vulva (woman's external genetalia) (With Roumanian subtitles!):
Women's sexual organs (Discovery Channel video)
0:00-1:00 Intro
1:00  program begins
2:05   language
2:23  vulva
3:00  mons veneris (mons pubis)
3:27  urethreal meatus
3:40  labia majora and minora

A cartoon of the stages of labor.