Incremental cost of non‐invasive prenatal diagnosis versus invasive prenatal diagnosis of fetal sex in England

Abstract

Fetal sex determination is performed for women who carry X-linked conditions, for example Duchenne muscular dystrophy (DMD), or those associated with ambiguous genitalia, for example congenital adrenal hyperplasia (CAH). Non-invasive prenatal diagnosis (NIPD) using cell-free fetal DNA (cffDNA) in maternal plasma is an alternative to invasive prenatal diagnosis (IPD), which carries a 1% risk of miscarriage. This study aimed to evaluate the incremental cost of NIPD compared with IPD of fetal sex. Diagnostic accuracy, invasive testing rate, and pregnancy outcome following NIPD were ascertained from an audit of all cases referred to two laboratories in 2006 to 2009. Care pathways for DMD and CAH were established and key cost drivers for IPD and NIPD identified using costs derived from published estimates and local laboratory values. The differences in mean costs per pregnancy for NIPD versus IPD were small for DMD [mean difference - £87, 95% confidence interval (CI) - £303 to £131] and CAH (-£193, 95% CI - £301 to - £84). Testing costs associated with NIPD were offset by fewer women requiring invasive testing. The costs of NIPD and IPD of fetal sex are similar. NIPD can provide benefits for many women by avoiding the risks of invasive testing, without incurring additional costs.