Fetal growth restriction

Severe early-onset fetal growth restriction (FGR) is a concerning condition that can lead to significant morbidity and mortality among newborns. The ability to anticipate and monitor the progression of this condition through the use of umbilical artery Doppler indices is invaluable in managing affected pregnancies. A recent study published in the American Journal of Obstetrics & Gynecology MFM (Am J Obstet Gynecol MFM) provides a pivotal retrospective cohort analysis examining the risk factors and time intervals associated with the deterioration of Doppler indices in cases of FGR and the development of absent or reversed end-diastolic velocity (A/REDV).

The Study Overview

The study, which carries the Digital Object Identifier (DOI): 10.1016/j.ajogmf.2024.101283, was conducted over a 15-year period from 2005 to 2020. It evaluated a cohort comprising 985 singleton pregnancies with severe early-onset FGR, characterized by an estimated fetal weight (EFW) or abdominal circumference (AC) below the 3rd percentile.

The study’s key objective was to examine the risk factors leading to the development of A/REDV in the umbilical artery (UA) and to assess the time intervals from a normal UA end-diastolic velocity (EDV) – gauged by systolic to diastolic (S/D) ratio, pulsatility index (PI), or resistance index (RI) – to decreased EDV and ultimately, A/REDV.

Significant Findings

Researchers identified 79 (8%) fetuses in the cohort that progressed to A/REDV. The progression of Doppler deterioration was found to be significantly influenced by the gestational age at diagnosis. Early diagnosis at 20 0/7 to 23 6/7 weeks indicated a substantial increase in risk of progression to A/REDV with an adjusted odds ratio (AOR) of 4.88 (95% CI: 2.55–9.37). Even at 24 0/7 to 27 6/7 weeks, an increased risk was noted with an AOR of 1.56 (95% CI: 0.86-2.82) compared to later gestational ages of 28 0/7 to 31 6/7 weeks.

Another significant risk factor for the development of A/REDV was the presence of chronic hypertension (CHTN) in the mother, with an AOR of 2.37 (95% CI: 1.33–4.23). These findings highlight critical antenatal risk factors that can inform clinical surveillance strategies.

As for the deterioration intervals, the study revealed that significant progression from normal UA Doppler to A/REDV occurred after four weeks from the FGR diagnosis. Interestingly, the study reported that abnormal RI and PI were linked to a shorter time to progression to A/REDV when compared to the S/D ratio. This suggests that PI and RI may be more sensitive indicators for predicting the onset of A/REDV.

Clinical Impact and Future Directions

The outcomes of this study emphasize gestational age and pre-existing maternal conditions as important considerations in the risk stratification and monitoring of FGR. The insights gained are instrumental for clinicians in making informed decisions regarding surveillance frequency and potential interventions.

While the findings shed light on the natural history of UA Doppler index deterioration in severe early-onset FGR, they also underscore the need for additional research to validate these findings further and to explore potential interventions that could alter the prognosis of affected pregnancies.

Author Contributions and Affiliations

The research was led by Juliana Martins Gevaerd from the Eastern Virginia Medical School, Norfolk, VA, along with her colleagues Tetsuya Kawakita, Carole Barake, and others from various reputable institutions. The collective expertise of the authors from different centers reinforces the study’s credibility and the significance of its findings.

References

1. Martins Gevaerd, J. et al. (2024). Rate of Deterioration of Umbilical Artery Doppler Indices in Fetuses with Severe Early-Onset Fetal Growth Restriction, American Journal of Obstetrics & Gynecology MFM.
DOI: 10.1016/j.ajogmf.2024.101283

2. Baschat, A. A. (2004). Pathophysiology of fetal growth restriction: implications for diagnosis and surveillance. Obstetrical & Gynecological Survey, 59(8), 617–627.

3. Figueras, F. & Gardosi, J. (2011). Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management. American Journal of Obstetrics & Gynecology, 204(4), 288–300.

4. Crispi, F. & Gratacós, E. (2012). Fetal growth restriction: management and long-term outcomes. Seminars in Fetal & Neonatal Medicine, 17(3), 153–158.

5. Alfirevic, Z., Stampalija, T., & Roberts, D. (2013). Cervical stitch (cerclage) for preventing preterm birth in singleton pregnancy. Cochrane Database of Systematic Reviews, 2013(5).

Keywords

1. Fetal Growth Restriction Research
2. Umbilical Artery Doppler Analysis
3. FGR Doppler Index Deterioration
4. Early-Onset FGR Risk Factors
5. Absent or Reversed End-Diastolic Velocity

This comprehensive analysis underscores the critical importance of umbilical artery Doppler indices in managing severe early-onset FGR. With clear identification of risk factors aiding in the prediction of Doppler index deterioration, clinicians are better equipped to adapt management strategies accordingly, ultimately aiming to improve neonatal outcomes.