Modern concepts of low birth weight and fetal growth restriction

Abstract

The aim of this work is to study the state of the problem of the development of small-for-gestational-age fetus and fetal growth restriction over the past 5 years. A review of randomized trials of the PubMed database for the period of 2015 to 2020 was carried out. Experts reached an agreement on the definition of diagnostic criteria for small-for-gestational-age fetus and fetal growth restriction, a clinically valid classification was created, and the main monitoring strategies were developed. Due to the different pathogenesis, fetal growth restriction is divided into early and late. The observation algorithm includes tests that have shown higher sensitivity and specificity. There is no single standard for the median weight and abdominal circumference of a fetus, indicators of the reference range for fetal Doppler. Smoking cessation and taking acetylsalicylic acid at a dose of 150 mg at high risk of preeclampsia is recommended to prevent the small-for-gestational-age fetus and fetal growth restriction. The pregnancy management algorithm includes Doppler ultrasound examination of the umbilical artery, cardiotocography. If this pathology occurs before 32 weeks of pregnancy, the blood flow in ductus venosus is additionally examined, and after 32 weeks of pregnancy, the middle cerebral artery blood velocities and cerebroplacental ratio are assessed. Indicators of Doppler velocimetry and cardiotocography, which serve as criteria for early termination of pregnancy, are developed, measures are proposed to improve neonatal outcomes — prevention of respiratory distress syndrome at 24–34 weeks of gestation, as well as magnesium therapy for fetal neuroprotection. The problems of preventing fetal growth restriction and the algorithm for monitoring pregnant women who do not have risk factors for small-for-gestational-age fetus, management tactics and indications for delivery while slowing fetal weight gain remain unresolved.