Intrauterine growth restriction according to Peruvian customized curves: validation and diagnostic accuracy study

Tipiani-Rodríguez O.; Bocanegra-Becerra Y.L.; Huarag-Chavarry C.; Figueroa-Morales K.; Ponciano-Biaggi M.Á. · Revista Peruana de Ginecologia y Obstetricia (2024) · DOI: 10.31403/rpgo.v70i2593

Resumen

Introduction: There is no consensus on the growth curve to be used to assess fetal growth. Objectives: To validate customized curves and study their performance in the detection of neonates with intrauterine growth restriction (IUGR), as well as their diagnostic accuracy. Methods: Initially, customized curves were designed with 2,792 singleton fetuses from low-risk pregnancies; the optimal weight at 40 weeks = 1,496.202 + (64.379 x fetal sex) + (831.362 x maternal length) + (9.567 x pregestational weight) was calculated and combined with a standard proportionality function to adjust the weights according to gestational age. Subsequently, its performance was evaluated by applying it in a retrospective cohort of neonates aged 24–40 weeks born between 2018-2022 in a tertiary hospital in Lima-Peru. Twins and congenital anomalies were excluded. Results: A total of 6,598 neonates were studied. Customized curves showed good agreement with INTERGROWTH-21 (IG21) (kappa = 0.68; 95%CI = 0.62-0.74). They detected 2.8% of IUGR (184/6,598), similar to the 3.1% for IG21 (205/6,598). They showed high specificity and negative positive value (NPV) (97% and 98%; 95%CI = 97-98% and 98-99%, respectively). The risk for perinatal death (RR = 7.2; 95%CI = 4.6-11) and accuracy (96; 95%CI = 95-96%) were higher than those of the Fetal Medicine Foundation (FMF) (RR=3.6; 95%CI = 2.5-5.2 and accuracy= 89%; 95%CI = 88-89%, respectively). Conclusion: The customized Peruvian curves were reliable in assessing IUGR. Their detection capacity and diagnostic accuracy were similar to other international curves, although somewhat higher than those of the FMF.