子宫疤痕的位置和完整性取决于剖宫产时宫颈扩张的程度。

Position and integrity of uterine scar are determined by degree of cervical dilatation at time of Cesarean section.

机构信息

Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynecology, Cairo University, Kasr Al-Ainy University Hospital, Egypt.

Fetal Medicine Unit, St George's University Hospitals NHS Foundation Trust, University of London, London, UK.

出版信息

Ultrasound Obstet Gynecol. 2021 Mar;57(3):466-470. doi: 10.1002/uog.22053.

DOI:10.1002/uog.22053

PMID:32330331

Abstract

OBJECTIVE

Abnormal placental invasion is more common after an elective Cesarean delivery, suggesting that prelabor Cesarean section (CS) increases the likelihood of the CS scar being above the internal cervical os and predisposing to a scar pregnancy in the future. The aim of this study was to assess the location and integrity of the CS scar in postpartum women delivered by CS at different stages of labor.

METHODS

This was a prospective cohort study of women at term who underwent a CS for the first time. In all women, cervical dilatation was determined by digital examination at the time of the CS. All patients had a transvaginal ultrasound examination to assess the location of the CS scar in relation to the internal cervical os, as well as the presence of a scar niche.

RESULTS

A total of 407 pregnant women were recruited into the study: 103 with cervical dilatation ≤ 2 cm, 261 with cervical dilatation 3-7 cm and 43 with cervical dilatation ≥ 8 cm at the time of the CS. A statistically significant correlation was observed between cervical dilatation at the time of the CS and the position of the CS scar. The scar was positioned in the uterus above the internal cervical os in 97.1% (100/103) of women delivered at a cervical dilatation of 0-2 cm, whereas the scar was located at or below the internal cervical os in 97.7% (42/43) of cases delivered at a cervical dilatation of 8-10 cm (P < 0.001). A uterine-scar defect (niche) was observed in 38.1% (64/168) of women with the scar located above, compared with 18.0% (43/239) of those with the scar situated at or below, the internal cervical os (P < 0.001).

CONCLUSIONS

Prelabor and early-labor Cesarean delivery are associated with an increased prevalence of a scar in the uterine cavity as well as a scar niche. CS in late labor is associated with the uterine scar being situated in the endocervical canal and with a lower incidence of a niche. The position and integrity of the CS scar after prelabor and early-labor Cesarean delivery explain the predisposition to abnormal placental invasion in subsequent pregnancy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

摘要

目的

择期剖宫产术后胎盘异常侵入更为常见，这表明产前剖宫产术（CS）增加了 CS 疤痕位于宫颈内口上方的可能性，并为未来的疤痕妊娠埋下隐患。本研究旨在评估不同产程时行 CS 的产妇产后 CS 疤痕的位置和完整性。

方法

这是一项前瞻性队列研究，纳入初次行 CS 的足月产妇。所有产妇在 CS 时均行阴道指诊以确定宫颈扩张程度。所有患者均行经阴道超声检查以评估 CS 疤痕与宫颈内口的位置关系以及是否存在疤痕凹陷。

结果

共纳入 407 例孕妇：103 例宫颈扩张≤2cm，261 例宫颈扩张 3-7cm，43 例宫颈扩张≥8cm。CS 时宫颈扩张程度与 CS 疤痕的位置存在显著相关性。宫颈扩张 0-2cm 时，97.1%（100/103）的产妇 CS 疤痕位于子宫内口上方，而宫颈扩张 8-10cm 时，97.7%（42/43）的产妇 CS 疤痕位于宫颈内口或下方（P＜0.001）。位于子宫内口上方的疤痕中有 38.1%（64/168）存在子宫-疤痕缺陷（凹陷），而位于宫颈内口或下方的疤痕中有 18.0%（43/239）存在子宫-疤痕缺陷（凹陷）（P＜0.001）。