The Role of First Trimester Ultrasonography in Antenatal Care: A Study from a Single Perinatal Institute in India

Abstract

The aim of this study was to assess the role of ultrasound in first the trimester of pregnancy for confirmation of pregnancy, number of fetuses, chorionicity, amnionicity if multiples, viability, assessment of gestational age, identification of structural anomalies and assessment of risk for chromosomal abnormalities. This was a prospective observational study. All pregnant women registered within 13⁺⁶ weeks were offered a routine scan between 11⁺⁰ and 13⁺⁶ weeks. All scans were done by obstetricians, fetal medicine specialists or radiologists are accredited by the Fetal Medicine Foundation. All pregnant women undergoing 11⁺⁰ and 13⁺⁶ weeks scan were included. Women beyond 14 weeks of pregnancy and referrals from the other centres not delivered at our institute were excluded from the study. A total of 5923 scans were done between January 2016 and June 2017. Complete follow up was available for 2927 women (49.4%), 1925 (32.5%) are ongoing pregnancies and 1071 (18.08%) pregnant women were lost to follow up. The median maternal age in our study was 28 years and 349 (5.89%) mothers had advanced (> 35 years) maternal age. Increased nuchal translucency (NT) (> 95th percentile) was found in 272 cases (4.59%). Intra-uterine fetal death, miscarriages, termination of pregnancy and cardiac abnormalities were higher among women with an NT > 95th percentile. Statistical analysis included calculation of p values and odd’s ratio. Skull and brain abnormalities were found in 28 cases, cystic hygroma in 20 cases, abdominal wall and spine abnormalities in 16 cases each, bladder abnormalities in 12 cases and cardiac abnormalities in 9 cases. Among 2927 women, 85 (1.43%) were screen positive. After counselling, only 20 women underwent invasive testing. The 11⁺⁰ and 13⁺⁶ weeks scan helps in determination of fetal viability, gestational age, number of fetuses and chorionicity and screening fetuses at risk for trisomy by including screening for structural abnormalities and plan pregnancy/terminate accordingly.

Keywords

Nuchal translucency - Structural abnormalities - Trisomy - Karyotype

Publication History

Received: 02 June 2019

Accepted: 01 February 2020

Article published online:
05 May 2023