Caesarean delivery after TOL
Compared to AGA births, caesarean delivery after TOL risks were higher for SGA <5th percentile (9.1% versus 5.9%) and SGA <3rd percentile (10.2% versus 5.9%; Table 1 ). For SGA <5thpercentile, further stratification by gestational age reveals that the risks of caesarean delivery after TOL were higher for SGA <5th percentile births across each gestational age strata, but the highest risks were ≥41 weeks (15.2%). The lowest risk occurred from 39-40 weeks’ gestation, although SGA <5th percentile births had higher risks of caesarean delivery after TOL compared to AGA births (8.0% versus 5.6%). Again, these trends were mirrored, but more pronounced, for SGA <3rd percentile births.
The adjusted excess risk of caesarean delivery with TOL also had a “U” shaped association (Table 2 ). The magnitude of the risk was highest <34 weeks’ gestation where the driver of risk was primarily due to interaction. As gestation advanced, the CDE had proportionately greater effect and the interaction component played a smaller role. These trends were similar, but more pronounced, for SGA <3rd percentile births (Table 3 ).