Editing Caesarean section (section)

==Uses==
[[File:Cesarean section scar and linea nigra.JPG|thumb|right|A seven-week-old caesarean section [[scar]] and [[linea nigra]] visible on a 31-year-old mother: Longitudinal incisions are still sometimes used.]]
Caesarean section (C-section) is recommended when [[vaginal delivery]] might pose a risk to the mother or baby. C-sections are also carried out for personal and social reasons on [[Caesarean delivery on maternal request|maternal request]] in some countries.

===Medical uses===
Complications of labor and factors increasing the risk associated with vaginal delivery include:
* Abnormal presentation ([[Breech birth|breech]] or [[:wikt:transverse|transverse positions]])
* Prolonged [[Childbirth|labor]] or a failure to progress ([[obstructed labour]], also known as dystocia)
* [[Fetal distress]]
* [[Cord prolapse]]
* [[Uterine rupture]] or an elevated risk thereof
* Uncontrolled [[hypertension]], [[pre-eclampsia]],<ref>{{cite journal | vauthors = Turner R |title=Caesarean Section Rates, Reasons for Operations Vary Between Countries |journal=[[Family Planning Perspectives]]|volume=22 |issue=6|pages=281–2 |year=1990 |doi=10.2307/2135690 |jstor=2135690 }}</ref> or [[eclampsia]] in the mother
* [[Tachycardia]] in the mother or baby after amniotic rupture (the waters breaking)
* [[Placenta]] problems ([[placenta praevia]], [[placental abruption]] or [[placenta accreta]])
* Failed [[labor induction]]
* Failed instrumental delivery (by [[Forceps in childbirth|forceps]] or [[ventouse]] (Sometimes, a trial of forceps/ventouse delivery is attempted, and if unsuccessful, the baby will need to be delivered by caesarean section.)
* Large baby weighing > 4,000 grams ([[macrosomia]])
* Umbilical cord abnormalities ([[vasa previa]], multilobate including bilobate and succenturiate-lobed placentas, [[velamentous insertion]])

Other complications of pregnancy, pre-existing conditions, and concomitant diseases, include:
* Previous (high risk) fetus
* [[HIV]] infection of the mother with a high [[viral load]] (HIV with a low maternal viral load is not necessarily an indication for caesarean section)
* An outbreak of [[genital herpes]] in the third trimester<ref>{{cite web |title=Management of Genital Herpes in Pregnancy |url=https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/05/management-of-genital-herpes-in-pregnancy |archive-url=https://archive.today/20210116112656/https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2020/05/management-of-genital-herpes-in-pregnancy |url-status=dead |archive-date=16 January 2021 |website=ACOG |access-date=3 May 2020 |date=May 2020 }}</ref> (which can cause infection in the baby if born vaginally)
* Previous classical (longitudinal) caesarean section
* Previous uterine rupture
* Prior problems with the healing of the [[perineum]] (from previous childbirth or [[Crohn's disease]])
* [[Bicornuate uterus]]
* Rare cases of [[posthumous birth]] after the death of the mother

Other
* Decreasing experience of accoucheurs with the management of breech presentation. Although obstetricians and midwives are extensively trained in proper procedures for breech presentation deliveries using simulation mannequins, there is decreasing experience with actual vaginal breech delivery, which may increase the risk.<ref name=Savage07>{{cite journal | vauthors = Savage W | title = The rising caesarean section rate: a loss of obstetric skill? | journal = Journal of Obstetrics and Gynaecology | volume = 27 | issue = 4 | pages = 339–346 | date = May 2007 | pmid = 17654182 | doi = 10.1080/01443610701337916 | s2cid = 27545840 }}</ref>

===Prevention===
The prevalence of caesarean section is generally agreed to be higher than needed in many countries, and physicians are encouraged to actively lower the rate, as a caesarean rate higher than 10–15% is not associated with reductions in maternal or infant mortality rates,<ref name="WHO2015" /> although some evidence support that a higher rate of 19% may result in better outcomes.<ref name=Mol2015/>

Some of these efforts include emphasizing a long [[Childbirth#First stage|latent phase]] of labor is not abnormal and not a justification for C-section; a new definition of the start of active labor from a cervical dilatation of 4&nbsp;cm to a dilatation of 6&nbsp;cm; and allowing women who have previously given birth to push for at least 2 hours, with 3 hours of pushing for women who have not previously given birth, before [[Tocolytic|labor arrest]] is considered.<ref name=ACOG2014/> [[Physical exercise]] during pregnancy decreases the risk.<ref>{{cite journal | vauthors = Domenjoz I, Kayser B, Boulvain M | title = Effect of physical activity during pregnancy on mode of delivery | journal = American Journal of Obstetrics and Gynecology | volume = 211 | issue = 4 | pages = 401.e1–401.11 | date = October 2014 | pmid = 24631706 | doi = 10.1016/j.ajog.2014.03.030 }}</ref> Additionally, results from a 2021 systematic review of the evidence on outpatient [[cervical ripening]] found that in women with low-risk pregnancies, the risk of caesarean delivery with harm to the mother or child was not significantly different from when done in an inpatient setting.<ref>{{Cite book | vauthors = McDonagh M, Skelly AC, Hermesch A, Tilden E, Brodt ED, Dana T, Ramirez S, Fu R, Kantner SN, Hsu F, Hart E |url=http://www.ncbi.nlm.nih.gov/books/NBK569292/ |title=Cervical Ripening in the Outpatient Setting |date=2021 |publisher=Agency for Healthcare Research and Quality (US) |series=AHRQ Comparative Effectiveness Reviews |location=Rockville (MD) |pmid=33818996}}</ref>