Articles Tập 67 Số CĐ1-NCKH 27/01/2026

MORPHOLOGICAL CHANGES OF THE CERVIX IN PREGNANT WOMEN WITH HIGH RISK OF PRETERM BIRTH BEFORE 34 WEEKS AT HANOI OBSTETRICS & GYNECOLOGY HOSPITAL.

Le Quang Hoa1,2, Mai Trong Hung1,2,3,4, Truong Quang Vinh3,4, Pham Duc Anh3,4, Do Xuan Hai3,4
1 Hanoi Obstetrics and Gynecology Hospital
2 Bệnh viện Phụ Sản Hà Nội
3 University of Medicine and Pharmacy, Vietnam National University, Hanoi
4 Trường Đại học Y Dược, Đại học Quốc gia Hà Nội
DOI: 10.52163/yhc.v67iCD1.4228
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Keywords
Preterm birth, cervix, transvaginal ultrasound, cervical morphology, prediction.
Abstract

Objective: This study aims to describe morphological changes of the cervix using transvaginal ultrasound in high-risk pregnant women and to determine the predictive value of these changes for preterm birth.

Method: A prospective descriptive study was conducted on 182 high-risk pregnant women at Hanoi Obstetrics and Gynecology Hospital from June 2024 to August 2025. A total of 1227 transvaginal ultrasound examinations were performed periodically from week 16 to week 34 of pregnancy. The parameters measured included cervical length, internal os shape (T, Y shapes), functional cervical length, and internal os dilation. The data was statistically analyzed to determine the predictive thresholds for preterm birth.

Results: The rate of preterm birth in the study group was 18.1%. The T-shape cervix accounted for 80.4%, while the Y-shape accounted for 19.6%. The average cervical length was 33.0±3.6 mm and gradually decreased with gestational age. There was a statistically significant difference between the < 34 weeks preterm birth group and the ≥ 34 weeks birth group. In pregnant women with cervical morphological changes (Y-shape), the functional cervical length was significantly shorter. The prognostic value of cervical length for preterm birth varies by gestational age and cervical morphology. Cervical length in T-shaped cervices has low prognostic value. However, functional cervical length in Y-shaped cervices demonstrates high prognostic value at specific gestational ages: at 22-24 weeks, the optimal cutoff is ≤ 33 mm (sensitivity 84.62%, specificity 83.33%); at 25-27 weeks, it is ≤ 28 mm (sensitivity 76.47%, specificity 72.00%); at 28-30 weeks, it is ≤ 26 mm (sensitivity 62.07%, specificity 83.58%); and at 31-34 weeks, it is ≤ 25 mm (sensitivity 85.71%, specificity 54.69%).

Conclusion: Transvaginal ultrasound of cervical morphology is an effective and highly valuable method for predicting the risk of preterm birth in high-risk pregnant women. Cervical morphological change from T shape to Y shape with short functional cervical length is an important early sign, prompting timely and effective interventions.

 

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