Accurate dating is essential during early pregnancy. Serial sonographic evaluations are typically used, but the best interval between assessments has not been clearly established. Given that a prior SGA newborn is associated with other adverse outcomes in a subsequent pregnancy, particularly stillbirth and preterm birth, surveillance during a subsequent pregnancy may be beneicial (Mendez-Figueroa, 2016; Spong, 2012). he American College of Obstetricians and Gynecologists (2015) notes that if growth is normal during a pregnancy following a prior pregnancy complicated by fetal-growth restriction, then Doppler velocimetry and fetal surveillance are not indicated. A recent metaanalysis of 45 trials involving 20,909 women reported that low-dose aspirin initiated prior to 16 weeks' gestation was associated with a significantly lower risk of fetal-growth restriction (Roberge, 2017). Moreover, they described a dose-response efect. he American College of Obstetricians and Gynecologists (2015) has not endorsed prophylaxis with low-dose aspirin for women with a prior growth-restricted fetus.
If fetal-growth restriction is suspected, then eforts are made to conirm the diagnosis, assess fetal condition, and search for possible causes. Early-onset growth restriction is especially problematic. In pregnancies in which fetal anomalies are suspected, patient counseling and prenatal diagnostic testing are indicated (American College of Obstetricians and Gynecologists, 2015).
Ifnoindications for immediate delivery, Ifnoindications for immediate delivery: begin antepartum fetal surveillance: -Antepartum fetal surveillance-BPP, NST, etc. -Regular fetal testing -Umbilical artery Doppler velocimetry weekly -Weekly umbilical artery Doppler velocimetry -Amnionic fluid evaluation weekly -Weekly evaluation of amnionic fluid surveillance until delivery 38 weeks, then deliver delivery 34 weeks, then begin
FIGURE 44-9 Algorithm for management of fetal-growth restriction at Parkland Hospital. BPP = biophysical profile; NST = nonstress test.
One management algorithm is shown in Figure 44-9. In pregnancies with suspected fetal-growth restriction, antepartum fetal surveillance includes periodic Doppler velocimetry of the umbilical arteries in addition to more frequent fetal testing. At Parkland Hospital, for women whose fetus measures ;3rd percentile and has reached a viable age, we encourage hospitalization on our High-Risk Pregnancy Unit. Daily fetal heart rate tracings, weekly Doppler velocimetry, and sonographic assessment of fetal growth every 3 to 4 weeks are initiated. Other modalities of Doppler velocimetry, such as middle cerebral arteries or ductus venosus assessment, are considered experimental. he American College of Obstetricians and Gynecologists (2015) recommends that antenatal corticosteroids for pulmonary maturation be given to pregnancies complicated by fetal-growth restriction and at risk for birth before 34 weeks' gestation.
he timing of delivery is crucial, and the risks of fetal death versus the hazards of preterm birth must be considered. Several multicenter studies address these problems, but unfortunately, none have elucidated the optimal timing of delivery. For the preterm fetus, the only randomized trial of delivery timing is the Growth Restriction Intervention Trial (GRIT) (hornton, 2004). This trial involved 548 women between 24 and 36 weeks' gestation with clinical uncertainty regarding delivery timing. Women were randomly assigned to immediate delivery or to delayed delivery until the situation worsened. he primary outcome was perinatal death or disability after reaching age 2 years. Mortality rates did not difer through 2 years of age. Moreover, children aged 6 to 13 years did not show clinically signiicant diferences between the two groups (Walker, 2011).