FIGO (international Federation of Gynecology and obstetrics) initiative on fetal growth: best practice advice for screening, diagnosis, and management of fetal growth restriction

Abstract

Fetal growth restriction (FGR) is defined as the failure of the fetus to meet its growth potential due to a pathological factor, most commonly placental dysfunction. Worldwide, FGR is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Ongoing advances in clinical care, especially in definitions, diagnosis, and management of FGR, require efforts to effectively translate these changes to the wide range of obstetric care providers. This article highlights agreements based on current research in the diagnosis and management of FGR, and the areas that need more research to provide further clarification of recommendations. The purpose of this article is to provide a comprehensive summary of available evidence along with practical recommendations concerning the care of pregnancies at risk of or complicated by FGR, with the overall goal to decrease the risk of stillbirth and neonatal mortality and morbidity associated with this condition. To achieve these goals, FIGO (the International Federation of Gynecology and Obstetrics) brought together international experts to review and summarize current knowledge of FGR. This summary is directed at multiple stakeholders, including healthcare providers, healthcare delivery organizations and providers, FIGO member societies, and professional organizations. Recognizing the variation in the resources and expertise available for the management of FGR in different countries or regions, this article attempts to take into consideration the unique aspects of antenatal care in low-resource settings (labelled “LRS” in the recommendations). This was achieved by collaboration with authors and FIGO member societies from low-resource settings such as India, Sub-Saharan Africa, the Middle East, and Latin America.

Keywords: FIGO initiative; Fetal growth restriction; detection; diagnosis; management; monitoring.

FIGURE 1A

Approach to screening, diagnosis, and management of fetal growth restriction in high‐resource settings. Abbreviations: FGR, fetal growth restriction; NST, nonstress test; PCR, polymerase chain reaction; SFH, symphysis–fundal height.

FIGURE 1B

Approach to screening, diagnosis, and management of fetal growth restriction in low‐resource settings. Abbreviations: FGR, fetal growth restriction; NST, nonstress test; PCR, polymerase chain reaction; SFH, symphysis–fundal height.

FIGURE 2

Comparison of the 10th percentile curves of common growth charts. Key: Hadlock: ultrasound‐based chart ¹⁹³ ; NICHD, National Institute of Child Health and Human Development chart ¹⁹⁸ ; IG21, Intergrowth‐21st chart ¹⁹⁶ ; WHO, World Health Organization chart ¹⁹⁷ Alexander: birth weight‐based chart. ¹⁹² [Colour figure can be viewed at wileyonlinelibrary.com]

FIGURE 3

Illustration of the statistical validation of two charts in a local population. The left chart shows a good match to the population of interest: the distribution of fetal weight percentiles based on this chart follows a normal distribution that is centered at the 50th percentile, with approximately 10% of the population below the 10th and above the 90th percentile. The right chart shows a poor fit for the population of interest as it is skewed to the right: it overdiagnoses fetuses as large for gestational age and underdiagnoses small‐for‐gestational‐age fetuses. [Colour figure can be viewed at wileyonlinelibrary.com]

FIGURE 4

Illustration of the impact of the growth chart chosen on the trade‐off between detection rate and false‐positive rate of fetuses at risk of adverse outcome. Charts that are shifted upward (light blue dotted line) will have a higher detection rate for pregnancies at risk of adverse outcomes (red circles) but would also have a higher false‐positive rate (i.e. identify normal pregnancies [green circle] as being at risk). In contrast, charts that are shifted downward (dark blue solid line) will have a lower false‐positive rate (i.e. identify fewer normal pregnancies [green circle] as being at risk) but will also have a lower detection rate for pregnancies at risk of adverse outcomes (red circles). [Colour figure can be viewed at wileyonlinelibrary.com]

FIGURE 5

Delivery criteria for fetal growth restriction. Delivery criteria are based on monitoring with umbilical artery, ductus venosus, and middle cerebral artery Doppler at specified gestational ages with traditional nonstress testing or computerized CTG (cCTG) if available. Abbreviations: NICU, neonatal intensive care unit; FHR, fetal heart rate; CTG, cardiotocogram; STV, short‐term variation; ms, milliseconds; EFW, estimated fetal weight; PI, pulsatility index. [Colour figure can be viewed at wileyonlinelibrary.com]