Editing Recurrent miscarriage (section)

=== Anatomical conditions ===
Fifteen percent of women who have experienced three or more recurring miscarriages have some anatomical reason for the inability to complete the pregnancy.{{sfn|Hoffman|page=181}} The structure of the [[uterus]] has an effect on the ability to carry a child to term. Anatomical differences are common and can be congenital or acquired.

* '''Congenital''': Congenital uterine malformations include [[Unicornuate uterus|unicornuate]], [[Septate uterus|septate]], [[Bicornuate uterus|bicornate]], [[Uterus didelphys|didelphic]], and [[Arcuate uterus|arcuate uteri]]. The relationship between uterine abnormalities that are present from birth and RPL is unclear, however, there is an association with pregnancy loss. These structural anomalies are a result of disruption of the Müllerian tract during development. These can be found in approximately 12.6% of RPL cases with the highest incidences occurring in patients with septate (44.3%), bicornuate (36%), and arcuate (25.7%) uteri. These Structural uterine abnormalities can be visualized by several imaging studies including, [[hysterosalpingography]], ultrasound, and MRI.<ref name="Fertility and Sterility_2012_2" />
* '''Acquired''': Other structural uterine anomalies such as [[uterine fibroid]]s, [[Endometrial polyp|polyps]], and adhesions (also known as [[Asherman's syndrome]]) have a less clear association with recurrent pregnancy loss.<ref name="Fertility and Sterility_2012_2" /> [[Cervical weakness]] has been shown to lead to premature pregnancy loss resulting in miscarriages or preterm deliveries. It has been estimated that cervical insufficiency is a cause in about 8% of women with second trimester recurrent miscarriages.<ref>{{cite journal | vauthors = Alfirevic Z, Stampalija T, Medley N | title = Cervical stitch (cerclage) for preventing preterm birth in singleton pregnancy | journal = The Cochrane Database of Systematic Reviews | volume = 2017 | issue = 6 | pages = CD008991 | date = June 2017 | pmid = 28586127 | pmc = 6481522 | doi = 10.1002/14651858.CD008991.pub3 | editor-last = Cochrane Pregnancy and Childbirth Group }}</ref>