Mid-Gestation Assessment of Small-for-Gestational-Age Risk – Medscape

Report on Mid-Gestation Risk Assessment for Small for Gestational Age (SGA) Pregnancies

Introduction

This report presents findings from a large-scale prospective study assessing the risk of small for gestational age (SGA) fetuses at mid-gestation (19+0 to 23+6 weeks). The study emphasizes the integration of maternal risk factors, estimated fetal weight, and uterine artery pulsatility index (UtA-PI) to identify pregnancies requiring enhanced monitoring. This approach aligns with Sustainable Development Goals (SDGs) 3 (Good Health and Well-being) and 10 (Reduced Inequalities) by promoting early detection and improved maternal-fetal health outcomes.

Methodology

1. A prospective, non-intervention study was conducted involving 134,443 women with singleton pregnancies undergoing routine ultrasound scans between January 2011 and May 2024 at 19+0 to 23+6 weeks gestation.
2. Maternal risk factors were combined with estimated fetal weight and UtA-PI measurements to predict SGA risk.
3. Risk cutoffs were established to detect approximately 80%, 85%, and 90% of SGA deliveries occurring before 28, 32, and 36 weeks gestation, respectively.
4. Primary outcomes focused on deliveries of neonates with birth weights below the 10th and 3rd percentiles at specified gestational ages.

Key Findings

• 12.51% of singleton pregnancies resulted in SGA neonates with birth weight below the 10th percentile:
  • 0.15% delivered before 28 weeks
  • 0.42% delivered before 32 weeks
  • 1.33% delivered before 36 weeks
• 5.15% of pregnancies delivered neonates with birth weight below the 3rd percentile:
  • 0.11% before 28 weeks
  • 0.33% before 32 weeks
  • 0.92% before 36 weeks
• Screen positive rates to detect 80% of SGA neonates (<10th percentile) were:
  • 9.5% at <28 weeks
  • 19.6% at <32 weeks
  • 29.6% at <36 weeks
• Screen positive rates to detect 80% of SGA neonates (<3rd percentile) were:
  • 6.5% at <28 weeks
  • 13.0% at <32 weeks
  • 21.6% at <36 weeks

Implications for Sustainable Development Goals

• SDG 3 – Good Health and Well-being: Early identification of SGA risk enables timely interventions and monitoring, potentially reducing neonatal morbidity and mortality.
• SDG 10 – Reduced Inequalities: Stratified risk assessment supports equitable allocation of healthcare resources by targeting high-risk pregnancies for enhanced surveillance.
• SDG 9 – Industry, Innovation and Infrastructure: Utilization of advanced ultrasound technologies and integrated risk models exemplifies innovation in prenatal care.

Clinical Practice Recommendations

The study authors recommend implementing a stratification plan based on second trimester integrated risk assessment to guide targeted ultrasound scans between 24 and 36 weeks gestation. This approach may improve management of SGA pregnancies by facilitating timely clinical interventions.

Study Limitations

• The findings are limited to singleton pregnancies and may not generalize to multiple gestations.
• Risk cutoffs for management groups may vary depending on local healthcare resources and preferences.
• Changes in antenatal care practices over the 13-year study period could have influenced results, although measurement techniques remained consistent.

Source and Funding

This study was led by Dr. Ioannis Papastefanou at the Fetal Medicine Research Institute, King’s College Hospital, London, England. The full article was published online on June 12, 2025, in the American Journal of Obstetrics and Gynecology. The research received funding from the Fetal Medicine Foundation, with no reported conflicts of interest.

Conclusion

The integration of maternal risk factors with fetal biometry and UtA-PI at mid-gestation offers a promising strategy to identify pregnancies at risk for SGA. This aligns with global health objectives under the Sustainable Development Goals to enhance maternal and neonatal health through early detection and targeted care.

1. Sustainable Development Goals (SDGs) Addressed or Connected

1. SDG 3: Good Health and Well-being
   • The article focuses on improving prenatal care and monitoring for small for gestational age (SGA) neonates, directly relating to ensuring healthy lives and promoting well-being at all ages.
2. SDG 2: Zero Hunger
   • SGA is often linked to maternal nutrition and fetal growth, which connects to ending all forms of malnutrition and addressing nutritional needs during pregnancy.

2. Specific Targets Under Those SDGs Identified

1. SDG 3: Good Health and Well-being
   • Target 3.1: Reduce the global maternal mortality ratio.
   • Target 3.2: End preventable deaths of newborns and children under 5 years of age.
   • Target 3.8: Achieve universal health coverage, including access to quality essential health-care services.
2. SDG 2: Zero Hunger
   • Target 2.2: End all forms of malnutrition, including achieving targets on stunted and wasted children under 5 years of age.

3. Indicators Mentioned or Implied to Measure Progress

1. Indicators Related to SDG 3
   • Proportion of pregnancies delivering SGA neonates with birth weight less than the 10th and 3rd percentiles at various gestational ages (< 28, < 32, < 36 weeks).
   • Screen positive rates for detecting SGA neonates at different gestational ages.
   • Use of ultrasound scans and uterine artery pulsatility index (UtA-PI) as diagnostic tools to monitor fetal growth and risk stratification.
2. Indicators Related to SDG 2
   • Incidence rates of SGA neonates as a proxy for fetal malnutrition or growth restriction.

4. Table: SDGs, Targets and Indicators

Source: medscape.com