Serial scans and stillbirth risk
The 318,768 (24.4%) pregnancies that were recorded as high risk had a shorter median length of pregnancy (273 vs 279 days, p <0.01) and a 70% higher rate of stillbirth compared to pregnancies designated low risk (Table 2). In this high-risk group, 289,285 pregnancies (90.8%) were monitored with serial scans according to protocol, and had a stillbirth rate of 5.64 (RR compared to low risk: 1.6, CI 1.5-1.7). Pregnancies which did not receive serial scans had a stillbirth rate that was more than twice as high as those that did have serial scans: 11.94 (RR compared to low risk: 3.3, CI 3.0-3.7).