Fetal abdominal subcutaneous tissue thickness measured by ultrasound at term is associated with birth weight and mode of delivery.

PURPOSE: To determine if measurement of fetal abdominal subcutaneous tissue thickness (FASTT) at term can predict birth weight, mode of delivery and perinatal outcome. METHODS: A prospective study with 352 normal, singleton pregnancies in the vertex presentation examined with real-time ultrasound at 37-39 weeks' gestation. RESULTS: FASTT was positively correlated with birth weight (Pearson's, r = 0.784, p < 0.001). Fetuses with low FASTT were more likely to be delivered through normal vaginal delivery (7.8 +/- 0.1 mm), while higher FASTT was correlated with operative vaginal delivery (7.9 +/- 0.2 mm) and cesarean section (8.6 +/- 0.3 mm) (ANOVA, p = 0.034). In contrast, FASTT was not correlated with intrapartum CTG, labor duration and Apgar scores. CONCLUSIONS: In normal pregnancies, FASTT at term is positively associated with birth weight. With increasing FASTT the likelihood of operative vaginal and cesarean delivery increases. FASTT is not associated with perinatal outcome.

Nuchal cord detected by ultrasound at term is associated with mode of delivery and perinatal outcome.

OBJECTIVES: To evaluate the clinical relevance of nuchal cord in normal, vertex, singleton pregnancies at term, and its effect on mode of delivery and perinatal outcome. STUDY DESIGN: Prospective study with 352 normal, singleton pregnancies, with fetuses in the vertex presentation, examined with real-time ultrasound at 37-39 weeks. Health care workers at labour and delivery blinded to previous detection of nuchal cord. RESULTS: Fetuses of nulliparous women with a nuchal cord were more likely to be delivered with operative vaginal or caesarean delivery (n = 153, p < 0.0001). This was not the case with higher parity (n = 199, p = 0.07). There was no difference between nuchal cord (n = 144) and control groups (n = 208) in amniotic fluid quantity at 37-39 weeks (p = 0.554) or intrapartum CTG (p = 0.9). On the other hand, nuchal cord group had lower Apgar scores at 1 and 5 min (p = 0.001 and 0.027 respectively); this difference remained significant when adjusted for birth weight (p = 0.001 and 0.016), but disappeared when adjusted for mode of delivery (p = 0.048 and 0.319). CONCLUSIONS: Nuchal cord in normal pregnancies at term is associated with increased rate of operative vaginal and caesarean delivery in nulliparae. The presence of a nuchal cord results in slightly lower Apgar scores at 1 and 5 min, mainly as a consequence of higher operative delivery rates.