Cost-Effectiveness of universal routine sonographic cervical-length measurement at 19-25 weeks' gestation.

BACKGROUND: Anational second trimester scanning of cervical length (CL) was introduced in Israel in 2010, and in the decade after a significant systematic reduction in preterm birth (PTB) and in the delivery of low birthweight (LBW) babies was found among singletons.

OBJECTIVE(S): Here we set to estimate the cost-effectiveness of a national policy mandating second-trimester cervical length (CL) screening by ultrasound followed by vaginal progesterone treatment for short CL compared to no screening strategy.

STUDY DESIGN: We constructed a decision model comparing two strategies (1) universal Cl screening, and (2) no screening strategy. The strategies use the national delivery registry of Israel's Ministry of Health (IMOH). All women diagnosed with a second trimester CL shorter than 25 mm were treated with vaginal progesterone and were monitored by ultrasound scan bi-monthly for cervical dynamics and threat of early delivery. PTB prevalence related to short CL, the efficacy of progesterone in PTB prevention, and the accuracy of CL measurements are derived from previous studies. The cost of progesterone and bi-monthly sonographic surveillance, LBW delivery and newborn admission to intensive care units (NICU), the first-year costs of managing PTB and LBW, and instances of handicaps and the cost of their follow-up were extracted from the publicly posted registry of IMOH and Israel Social Securities (ISS) data. Monte Carlo simulations decision tree mode, Tornado diagrams, and one-and-two- way sensitivity analyses were implemented and the base case and sensitivity to parameters predicted to influence cost effectiveness were calculated.

RESULTS: Without CL screening the discounted QALY was 30.179 and with universal CL screening it increased to 30.198 (difference of 0.018 QALYs). The average cost of no screening for CL strategy was $1,047 and for universal CL screening it was reduced to $998 The calculated ICER was -$2,676 per QALY (dividing the difference in costs by the difference in QALYs). Monte Carlo simulation of CL screening of 170,000 singleton newborns (rounded large number close to the number of singleton newborns in Israel), shows that 95.17% of all babies were delivered at gestational week (GA) ≥37 compared to 94.46 % in no screening strategy. Given 170,000 singleton births, the national savings of screening for short CL compared to no CL screening amounted to $8.31M annually, $48.84 for a base case, and the ICER for each case of LBW or VLBW avoided, was -$14,718 . CL< 25 mm was measured for 30,090 women, of which 24,650 were false positive. The major parameters affecting the ICER were the incidence of PTB, the specificity of CL measurements, and the efficacy of progesterone treatment. At PTB incidence of less than 3%, universal screening was not cost saving.

CONCLUSION: A national universal CL screening should be incorporated into the routine anomaly scan in the second trimester as it leads to a drop in the incidence of PTB and LBW in singleton pregnancies, saving cost of newborn and gaining QALYs.