33. REVIEW OF THE PREDICTIVE VALUE OF CERVICAL LENGTH AND CERVICAL ANGLE ON ULTRASOUND FROM WEEK 22-28 IN SINGLE PREGNANT WOMEN AT NINH BINH OBSTETRICS AND PEDIATRIC HOSPITAL IN 2024. YHCĐ [Internet]. 2025 May 31 [cited 2026 Sept. 9];66(CĐ6-HNKH Bệnh viện Sản nhi Nghệ An). Available from: https://tapchiyhcd.vn/index.php/yhcd/article/view/2299