This is the time, usually, when you will go to the hospital, if your baby is to be born there, or when you will notify your doctor that you think you are in labor. If you are to remain at home the doctor may want you to send for the nurse at once, in which case he depends upon her to communicate with him. Or he may prefer that you notify him and let him send the nurse. Either arrangement is simple and easy to carry out, but you must be sure that you understand just what the doctor wants you to do when you think labor has started. It is not a bad plan to write down his instructions about this, with the telephone number and street address of the one to be summoned, so that you will know exactly how to proceed when the time comes. [Illustration: FIG. 22.—Diagrams showing how the cervix is dilated as the bag of waters is forced downward by the uterine contractions. ] The entire duration of labor may vary from a few moments to several days, but the average length of the first labor is about eighteen hours and of subsequent births about twelve hours. The process is usually described as being divided into the first, second and third stages of labor, approximately as follows: _First stage_ _Second stage_ _Third stage_ _Total_ First labor 16 hours 1¾ hours 15 minutes 18 hours Later labors 11 hours 45 minutes 15 minutes 12 hours The first stage begins with the onset of labor and lasts until the cervical canal is completely dilated; the second stage begins when the cervix is dilated and lasts until the baby is born; the third stage begins with the birth of the baby and lasts until the afterbirth is expelled. =First Stage.= The pains are mild at first and occur at intervals of from fifteen to thirty minutes, but they gradually increase in frequency and intensity until by the end of fourteen to sixteen hours, they are very severe, and recur every three or four minutes, each pain lasting about one minute. The pains begin in the back, then pass slowly forward to the abdomen and down into the thighs. The average woman is entirely comfortable between pains and until they become very frequent she will usually prefer to be up and about, but if she is on her feet when a contraction begins she will usually seek relief by leaning forward on something secure, as the foot of the bed or a table, or by sitting down until the pain subsides. As time passes, there is an increasing, sometimes persistent desire to empty the bowels and bladder because of pressure upon these two organs by the baby’s head as it is forced slowly downward. There may be vomiting, also when the cervix becomes nearly, or quite dilated. In the course of the stretching process, the cervix sustains many tiny tears from which blood oozes and tinges the vaginal discharge. This bloodstained discharge is often called the “show” and usually appears toward the end of the first stage.