open access
Risk prediction of placenta previa based on the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy
Affiliations- Weifang Medical College Clinical Medical College, Weifang, China
- Obstetrics and Gynecology Department, Weifang People's Hospital, Weifang, China
- Sunshine Fusion Hospital, Weifang, China
- Ultrasound Department, Weifang People's Hospital, Weifang, China
open access
Abstract
Objectives: To explore the relationship between the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy and placenta previa.
Material and methods: A prospective cohort study of women who underwent pregnancy examination in Weifang People's Hospital or Sunshine Union Hospital from January 2020 to June 2021. The distance from the lower edge of the gestational sac to the internal cervical os was measured at 5–6 weeks’ gestation. There were 86 women with distance < 2.5 cm, and 105 women with distance ≥ 2.5 cm were randomly selected. There were 92 cases of scarred uterus and 99 cases of non-scarred uterus among the 191 women. They were divided into six groups according to the distance: (1) < 1.0 cm; (2) 1.0 cm to < 1.5 cm; (3) 1.5 cm to < 2.0cm; (4) 2.0 cm to < 2.5 cm; (5) 2.5 cm to < 3.0 cm; (6) ≥ 3.0 cm. All included women were followed-up during pregnancy and pregnancy outcome, and the likelihood ratio of different distances in early pregnancy was calculated and risk stratification was performed, and ROC curve was constructed.
Results: There were 15 women in the included studies who were lost to follow-up, 47 had a scarred uterus with placenta previa and 29 had a non-scarred uterus with placenta previa after delivery at 28 weeks or later. The distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy of the scarred uterus < 1.5 cm, and the likelihood ratio was ∞; and the distance ≥ 3.0 cm, the likelihood ratio was 0. The distance from the lower edge of the non-scarred gestational sac to the internal cervical os < 1.0 cm, and the likelihood ratio was ∞; and the distance ≥ 3.0 cm, the likelihood ratio was 0. The ROC curve showed that when the area AUC under the curve was 87%, the optimal diagnostic cut-off value was 2.4 cm.
Conclusions: When the distance from the lower edge of the gestational sac to the internal cervical os was < 1.5 cm and the distance between the non-scarred uterus was < 1.0 cm, it eventually developed into placenta previa; the distance from the lower edge of the gestational sac to the internal cervical os in the first trimester of pregnancy between the scarred uterus and the non-scarred uterus was ≥ 3.0 cm, and it would hardly develop into placenta previa. When the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy was ≤ 2.4 cm, it could be used as a predictor of placenta previa.
Abstract
Objectives: To explore the relationship between the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy and placenta previa.
Material and methods: A prospective cohort study of women who underwent pregnancy examination in Weifang People's Hospital or Sunshine Union Hospital from January 2020 to June 2021. The distance from the lower edge of the gestational sac to the internal cervical os was measured at 5–6 weeks’ gestation. There were 86 women with distance < 2.5 cm, and 105 women with distance ≥ 2.5 cm were randomly selected. There were 92 cases of scarred uterus and 99 cases of non-scarred uterus among the 191 women. They were divided into six groups according to the distance: (1) < 1.0 cm; (2) 1.0 cm to < 1.5 cm; (3) 1.5 cm to < 2.0cm; (4) 2.0 cm to < 2.5 cm; (5) 2.5 cm to < 3.0 cm; (6) ≥ 3.0 cm. All included women were followed-up during pregnancy and pregnancy outcome, and the likelihood ratio of different distances in early pregnancy was calculated and risk stratification was performed, and ROC curve was constructed.
Results: There were 15 women in the included studies who were lost to follow-up, 47 had a scarred uterus with placenta previa and 29 had a non-scarred uterus with placenta previa after delivery at 28 weeks or later. The distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy of the scarred uterus < 1.5 cm, and the likelihood ratio was ∞; and the distance ≥ 3.0 cm, the likelihood ratio was 0. The distance from the lower edge of the non-scarred gestational sac to the internal cervical os < 1.0 cm, and the likelihood ratio was ∞; and the distance ≥ 3.0 cm, the likelihood ratio was 0. The ROC curve showed that when the area AUC under the curve was 87%, the optimal diagnostic cut-off value was 2.4 cm.
Conclusions: When the distance from the lower edge of the gestational sac to the internal cervical os was < 1.5 cm and the distance between the non-scarred uterus was < 1.0 cm, it eventually developed into placenta previa; the distance from the lower edge of the gestational sac to the internal cervical os in the first trimester of pregnancy between the scarred uterus and the non-scarred uterus was ≥ 3.0 cm, and it would hardly develop into placenta previa. When the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy was ≤ 2.4 cm, it could be used as a predictor of placenta previa.
Keywords
early pregnancy; lower edge of the gestational sac; internal cervical os; placenta previa
About this articleTitle
Risk prediction of placenta previa based on the distance from the lower edge of the gestational sac to the internal cervical os in early pregnancy
Journal
Issue
Article type
Research paper
Published online
2023-04-21
Page views
285
Article views/downloads
314
DOI
Pubmed
Keywords
early pregnancy
lower edge of the gestational sac
internal cervical os
placenta previa
Authors
Yangyang Wang
Yujing Xu
Kai Sun
Wenjuan Gao
Yujian Lin
Zhenlan Wu
References (17)- Ersoy AO, Ozler S, Oztas E, et al. The association between placenta previa and leukocyte and platelet indices - a case control study. Ginekol Pol. 2016; 87(5): 367–371.
- Zhang LZ, Bi SL, Chen DJ, et al. Recognition and management of placenta implantation complicated with placenta previa. Chinese Journal of Practical Gynecology and Obstetrics. 2020; 36(02): 107–110.
- Zhang L, Bi S, Du L, et al. Effect of previous placenta previa on outcome of next pregnancy: a 10-year retrospective cohort study. BMC Pregnancy Childbirth. 2020; 20(1): 212.
- Li Y, Choi HH, Goldstein R, et al. Placental thickness correlates with placenta accreta spectrum (PAS) disorder in women with placenta previa. Abdom Radiol (NY). 2021; 46(6): 2722–2728.
- Naji O, Wynants L, Smith A, et al. Does the presence of a Caesarean section scar affect implantation site and early pregnancy outcome in women attending an early pregnancy assessment unit? Hum Reprod. 2013; 28(6): 1489–1496.
- Bi S, Zhang L, Wang Z, et al. Effect of types of placenta previa on maternal and neonatal outcomes: a 10-year retrospective cohort study. Arch Gynecol Obstet. 2021; 304(1): 65–72.
- Obstetrics Subgroup, Chinese Society of Obstetrics and Gynecology, Chinese Medical Association. Guidelines for the diagnosis and management of placenta previa . The Chinese Journal of Obstetrics and Gynecology. 2020; 55(1): 3–8.
- Kamel R, Eissa T, Sharaf M, et al. Position and integrity of uterine scar are determined by degree of cervical dilatation at time of Cesarean section. Ultrasound Obstet Gynecol. 2021; 57(3): 466–470.
- Marshall NE, Fu R, Guise JM. Impact of multiple cesarean deliveries on maternal morbidity: a systematic review. Am J Obstet Gynecol. 2011; 205(3): 262.e1–262.e8.
- Westerway SC, Hyett J, Henning Pedersen L. Measuring leading placental edge to internal cervical os: Transabdominal versus transvaginal approach. Australas J Ultrasound Med. 2017; 20(4): 163–167.
- Li X, Feng Y. Complete placenta previa in the second trimester: clinical and sonographic factors associated with its resolution. Ginekol Pol. 2019; 90(9): 539–543.
- Li C, Yang P, Luo H. Prediction of Delivery Complications by First-Trimester Ultrasound Measurement of the Gestational Sac's Distance From a Previous Cesarean Section Scar. J Ultrasound Med. 2020; 39(8): 1563–1571.
- Happe SK, Rac MWF, Moschos E, et al. Prospective First-Trimester Ultrasound Imaging of Low Implantation and Placenta Accreta Spectrum. J Ultrasound Med. 2020; 39(10): 1907–1915.
- Gibbins KJ, Einerson BD, Varner MW, et al. Placenta previa and maternal hemorrhagic morbidity. J Matern Fetal Neonatal Med. 2018; 31(4): 494–499.
- Liu XH, Zhou XQ, Dong Y, et al. Clinical Value of Different Bladder Separation Time in the Operation of Pernicious Placenta Previa with Severe Placenta Accreta. Journal of Practical Obstetrics and Gynecology. 2022; 38(05): 384–387.
- Xu YJ, Gao WJ, Xu XC, et al. 2020 ACR Interpretation of Guidelines for Imaging Examination of placenta accreta spectrum disorder. Progress in Obstetrics and Gynecology. 2021; 30(12): 954–956.
- Jauniaux E, Bhide A. Prenatal ultrasound diagnosis and outcome of placenta previa accreta after cesarean delivery: a systematic review and meta-analysis. Am J Obstet Gynecol. 2017; 217(1): 27–36.
