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Anatomy and physiology of the male reproductive system
Puberty and Tanner staging
Stages of labor
0 / 9 complete
brachial plexus injury in p. 457
Budd-Chiari syndrome and p. 401
contraction prevention p. 654
endometritis after p. 665
Graves disease and p. 348
low birth weight p. 658
misoprostol induction p. 408
neonatal flora p. 175
oxytocin p. 652
oxytocin for induction of p. 364
postpartum mood disturbances p. 585
preterm, as common cause of death p. 277
progesterone levels after p. 654
Sheehan syndrome after p. 351
stress incontinence and p. 624
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It specifically refers to the process which starts with uterine contractions which cause cervical changes which allow the fetus to be delivered vaginally, and ends with delivery of the placenta.
Labor typically begins at some point when the fetus is considered full term—between 37 and 42 weeks’ gestation.
Other times the amniotic sac might rupture, sometimes called “water breaking”.
These guys have to be distinguished from the milder and ineffective false labor contractions, also called Braxton Hicks contractions (or sometimes called practice contractions).
Once they start, true labor contractions progress in frequency, duration, and intensity, and they can feel like waves that build up to a peak intensity and then gradually decrease.
From the moment true contractions begin to the baby’s delivery usually takes about 12 to 18 hours for a first-time pregnancy, and about half that time for subsequent pregnancies.
Although, as any mother knows, this time can vary a lot!
Even though labor is a continuous process, it can be broken down into three stages.
Additionally, this first stage is subdivided into two phases.
The first phase is the early phase or latent phase, and usually lasts up to 20 hours, or until the cervix dilates to 6 centimeters.
At first, there are irregular contractions that occur every 5 - 30 minutes and last about 30 seconds each, causing the cervix to dilate from 0 cm to about 3 cm and efface from about 0% - 30%.
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