(1189) The effect of fetal surveillance on fetal outcomes in pregnancies with fetal growth restriction

There is no consensus regarding the appropriate follow-up frequency in fetal growth restriction (< 10th percentile;FGR). We examined whether FGR would benefit from careful monitoring with stratification for normal and pathological cerebro-placental ratio (CPR).

Study Design: This was a retrospective cohort study conducted between 2016 and 2020 in two medical centers. Women with suspected FGR (with (N=135) and without (N=269) pathological CPR underwent a strict monitoring regimen (1-2 well being assessments per week and Doppler flows once a week). These groups were compared to two control groups - fetuses identified only after birth as small for gestational age (SGA; N=693), and fetuses appropriate for gestational age (AGA; N=864) in which routine follow-up was done. Twins were excluded. The primary outcomes were (1) a composite outcome of cesarean deliveries (CD) due to suspected fetal distress, Apgar score< 7 at 5 min, cord pH< 7.1, neonatal intensive care unit admission, need for neonatal oxygen support and intrauterine fetal death, and (2) The rate of women in whom the strict follow-up led to induction of labor/CD before 37 weeks.. 

Results:

Study outcomes are presented in the table. The composite outcome was significantly different between the pathological CPR, normal CPR, SGA and AGA groups (61%, 34%, 24%, 12% respectively; P< 0.0001). Following logistic regression to control for background characteristics, the difference in the rate of the composite outcome was statistically significant between all groups except from the normal CPR group versus the SGA group (table).  The strict follow-up led to a higher rate of induction of labor/CD before week 37 in the group with the pathological CPR (23 [18%]) compared to those with normal CPR (11 [4%]), P< 0.0001.

Conclusion: The knowledge of FGR led to additional interventions, but without improving the outcomes of the newborn. CPR measurement may have a role in the assessment and adjustment of the follow-up plan. In cases where the CPR was normal, the rate of interventions before week 37 was low, and close follow-up may not be necessary in these cases.