Stillbirth at term in women of advanced maternal age in the United States: when could the antenatal testing be initiated?

Overview

We sought to determine if advanced maternal age (AMA) is a risk factor for intrauterine fetal demise (IUFD). We used a U.S. Centers for Disease Control and Prevention database and analyzed outcomes in women 15 to 44 years of age with term singleton gestations. Cox proportional hazards models and Cochran-Mantel-Haenszel tests were used. Results were controlled for maternal race and smoking. After excluding congenital anomalies and medical complications, 6,239,399 singleton term deliveries were identified. When compared with women 25 to 29 years of age, the risk of IUFD increased with advancing age: 30 to 34 years, odds ratio [OR] = 1.24 (95% confidence interval [CI], 1.13 to 1.36); 35 to 39 years, OR = 1.45 (95% CI, 1.21 to 1.74), and 40 to 44 years, OR = 3.04 (95% CI, 1.58 to 5.86). The risk of IUFD for women 40 to 44 years of age at 39 weeks is comparable with that of 42 weeks in those 25 to 29 years of age. We concluded that AMA is an independent predictor of IUFD, and a strategy of antenatal testing in those > or = 40 years of age beginning at 38 weeks may be considered.