Delay of Fetal Anatomy Ultrasound Assessment Based on Maternal Body Mass Index Does Not Reduce the Rate of Inadequate Visualization. (8th May 2020)

• Record Type: Journal Article
• Authors: Khaikin, Yannay; Bishop, Kelly A.; Munawar, Saleha; Pudwell, Jessica; Davies, Gregory A. L.
• Is Part Of: Journal of ultrasound in medicine. Volume 39:Number 11(2020)
• Page Start: 2123
• Page End: 2130
• Publication Date: 2020-05-08
• Subjects: body mass index -- fetal anatomy -- obesity -- prenatal diagnosis -- ultrasound; Ultrasonics in medicine -- Periodicals; Ultrasonics; Ultrasonography; Ultrasonics in medicine; Electronic journals; Periodicals; Periodicals; 616.07543
• DOI: 10.1002/jum.15319
• Languages: English
• ISSNs: 0278-4297

Abstract

Abstract : Objectives: To determine whether delay of initial anatomy ultrasound based on the maternal body mass index (BMI) reduces the rate of inadequate visualization compared to standard timing at 18 0/7 to 19 6/7 weeks. Methods: A retrospective study of singleton anatomy assessments was conducted at a tertiary care center in the 2‐year period before (A, 2012–2014) and after (B, 2014–2016) protocol initiation. Assessments in period B were scheduled on the basis of the BMI in the first trimester: lower than 25 kg/m 2, 18 0/7 to 19 6/7 weeks; 25 to 29.9 kg/m 2, 19 0/7 to 20 6/7 weeks; 30 to 34.9 kg/m 2, 20 0/7 to 21 6/7 weeks; 35 to 39.9 kg/m 2, 21 0/7 to 22 6/7 weeks; and 40 kg/m 2 or higher, 22 0/7 to 23 6/7 weeks. In period A, assessments were scheduled between 18 0/7 and 19 6/7 weeks. The rate of inadequate visualization and repeated assessments in periods A and B were compared. Multivariable logistic regression, per‐protocol, and BMI subgroup analyses were completed. Results: In total, 3491 pregnancies in period A and 3672 in period B were included. In period B, 74% were scheduled per protocol; however, this rate decreased for higher‐BMI categories (52% for BMI ≥40 kg/m 2 ). The inadequate visualization rate was slightly higher in period B versus A (16.9% versus 15.0%; P = .03) and exceeded 35% for a BMI of 40 kg/m 2 or higher, with or without delay. After adjusting for maternal age and fetal presentation, period B had small increased odds of inadequate visualization versus period A (adjusted odds ratio, 1.2; 95% confidence interval, 1.02–1.38). Repeated assessment rates were similar in periods B and A (14.0% versus 13.1%; P = .25). Conclusions: In pregnancies with obesity, a protocol delaying the initial assessment beyond 19 6/7 weeks based on the maternal BMI does not reduce the rate of inadequate visualization. Abstract : Access the CME test here and search by article title.