- Labor
- Childbirth, the aptly-named experience of delivering the baby and placenta from the uterus to the vagina to the outside world. There are two stages of labor. During the first stage (called the stage of dilatation), the cervix dilates fully to a diameter of about 10 cm. In the second stage (called the stage of expulsion), the baby moves out through the cervix and vagina to be born. The first stage of labor, the time when the cervix dilates, is conventionally divided into two phases: {{}}The latent phase — Contractions become progressively more coordinated and the cervix dilates to 4 cm. The latent phase averages about 8 hours in a nullipara (a woman having her first baby) and 5 hours in a multipara (a woman with multiple pregnancies). This phase is considered distinctly abnormal if it lasts more than 20 hours in a nullipara or more than 12 hours in a multigravida. The active phase — The cervix becomes fully dilated and the presenting part of the baby descends into the midpelvis. The active phase averages about 5 hours in nulliparas and 2 hours in multiparas. The second stage of labor, the time from full cervical dilation to the delivery of the baby, lasts on the average 2 hours in nulliparas and l hour in multiparas. It may last an additional hour if there is an epidural In a spontaneous delivery, the woman must supplement her uterine contractions by bearing down. In Latin, the word labor means "a troublesome effort or suffering." Parturition is another term for "labor." It comes from the Latin parturire, "to be ready to bear young" and is related to partus, "to produce." To labor in this sense is to produce.
* * *The process of expulsion of the fetus and the placenta from the uterus. The stages of l. include: first stage, beginning with the onset of uterine contractions through the period of dilation of the os uteri; second stage, the period of expulsive effort, beginning with complete dilation of the cervix and ending with expulsion of the infant; third s. or placental stage, the period beginning at the expulsion of the infant and ending with the completed expulsion of the placenta and membranes. [L. toil, suffering]- missed l. brief uterine contractions which do not lead to l. and expulsion of the infant, but which cease, resulting in the indefinite retention of the fetus (usually lifeless) either in utero or in the abdominal cavity.- premature l. onset of l. after 20 weeks and before the 37th completed week of pregnancy dated from the last normal menstrual period.- trial of l. after cesarean section the attempt to deliver vaginally after a cesarean section; carries some risk of rupture of the uterine scar.
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la·bor or Brit la·bour 'lā-bər n the physical activities involved in parturition consisting essentially of a prolonged series of involuntary contractions of the uterine musculature together with both reflex and voluntary contractions of the abdominal wall <drugs that induce \labor> <went into \labor after a fall> also the period of time during which such labor takes place* * *
la·bor (laґbər) [L. “workâ€] the function of the female organism by which the product of conception is expelled from the uterus through the vagina to the outside world. Labor may be divided into four stages: The first (the stage of cervical dilatation) begins with the onset of regular uterine contractions and ends when the os is completely dilated. The second stage (stage of expulsion) extends from the end of the first stage until the expulsion of the infant is completed. The third stage (placental stage) extends from the expulsion of the child until the placenta and membranes are expelled. The fourth stage denotes the hour or two after delivery, when uterine tone is established. See also labor pains, under pain.
Medical dictionary. 2011.