Application of ultrasonographic human estimated foetal weight formulas to cynomolgus monkeys (Macaca fascicularis) at 129–132 days of gestation: A comparative study of estimated and actual birthweight

• Published in: Veterinary medicine and science Vol. 10; no. 4; pp. e1521 - n/a
• Main Authors: Lee, Dong‐Ho, Yoon, Seung‐Bin, Kim, Ji‐Su, Mo, Jun Won, Jo, Yu‐Jin, Kwon, Jeongwoo, Lee, Sang Il, Kwon, Jungkee, Park, Chan‐Wook
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.07.2024; John Wiley and Sons Inc; Wiley
• Subjects: Abdomen; Accuracy; Animals; Birth Weight; Cesarean section; cynomolgus monkey; Female; Females; Femur; Fetal Weight - physiology; Fetuses; Gestation; Gestational age; human estimated foetal weight formulas; Humans; Macaca fascicularis; Macaca fascicularis - embryology; Macaca fascicularis - physiology; Medical research; Monkeys & apes; Original; OTHER; Pregnancy; Premature birth; Primates; Ultrasonic imaging; ultrasonography; Ultrasonography, Prenatal - veterinary; Veins & arteries; Veterinary medicine; cynomolgus monkey; human estimated foetal weight formulas; ultrasonography; pregnancy
• ISSN: 2053-1095; 2053-1095
• DOI: 10.1002/vms3.1521

Background Cynomolgus monkeys (Macaca fascicularis) are essential in biomedical research, including reproductive studies. However, the application of human estimated foetal weight (EFW) formulas using ultrasonography (USG) in these non‐human primates is not well established. Objectives This study aims to evaluate the applicability of human EFW formulas for estimating foetal weight in cynomolgus monkeys at approximately 130 days of gestation. Methods Our study involved nine pregnant cynomolgus monkeys. We measured foetal parameters, including biparietal diameter, head circumference, abdominal circumference and femur length using USG. The EFW was calculated using 11 human EFW formulas. The actual birthweight (ABW) was recorded following Cesarean section, the day after the EFW calculation. For comparing EFW and ABW, we employed statistical methods such as mean absolute percentage error (APE) and Bland–Altman analysis. Results The ABW ranged between 200.36 and 291.33 g. Among the 11 formulas, the Combs formula showed the lowest APE (4.3%) and highest correlation with ABW (p < 0.001). Notably, EFW and ABW differences for the Combs formula were ≤5% in 66.7% and ≤10% in 100% of cases. The Bland–Altman analysis supported these results, showing that all cases fell within the limits of agreement. Conclusions The Combs formula is applicable for estimating the weight of cynomolgus monkey fetuses with USG at approximately 130 days of gestation. Our observations suggest that the Combs formula can be applied in the prenatal care and biomedical research of this species. Ultrasonography (USG) is a crucial tool in human prenatal care for determining gestational age and evaluating foetal development. In our study, we measured foetal parameters in cynomolgus monkey fetuses at around 130 days of gestation using USG and applied 11 human estimated foetal weight formulas. Among these, the Combs formula showed a mean absolute percentage error of 4.3% and performed excellently across various statistical analyses, suggesting its applicability in prenatal care and research for cynomolgus monkeys.