Universal first-trimester cytomegalovirus screening and valaciclovir prophylaxis in pregnant persons: a cost-effectiveness analysis

BACKGROUND: Recent studies have suggested a possible benefit of valaciclovir prophylaxis to prevent vertical transmission after a positive serologic screen for primary maternal cytomegalovirus infection during pregnancy, although its cost-effectiveness remains uncertain. OBJECTIVE: This study aimed to determine the circumstances under which universal first-trimester maternal serologic screening for maternal cytomegalovirus infection, with valaciclovir prophylaxis to prevent congenital cytomegalovirus, is cost-effective. STUDY DESIGN: This study was a decision analysis from the perspective of the pregnant person to assess whether universal maternal screening in the first trimester of pregnancy, with subsequent valaciclovir prophylaxis (8 g/day from the time of positive serologic screen for primary maternal cytomegalovirus infection to 21 weeks of gestation) for those who are acutely infected, is cost-effective compared with usual care (ie, no routine serologic screening but with amniocentesis if midtrimester sonographic findings suggest cytomegalovirus). For baseline estimates, this study assumed a 35% risk of congenital cytomegalovirus after primary maternal infection and a 71% risk reduction with valaciclovir. This study varied valaciclovir's efficacy to identify whether and at what threshold universal screening would be estimated to be cost-effective, compared with usual care. Monte Carlo analyses were performed. A willingness-to-pay threshold of $100,000/quality-adjusted life year was used to define cost-effectiveness. RESULTS: Under base case estimates, first-trimester universal screening and valaciclovir prophylaxis for seropositive pregnant persons with acute cytomegalovirus infection were not cost-effective, with a cost of $137,854 per maternal quality-adjusted life year but resulted in 14 fewer children affected with cytomegalovirus per 100,000 pregnancies compared with usual care. In 1-way sensitivity analysis, universal screening and treatment were estimated to be the cost-effective strategy if the incidence of primary maternal cytomegalovirus infection exceeds 2.6%, the baseline risk of vertical transmission of cytomegalovirus without prophylaxis is greater than 36.8%, and the risk reduction of vertical transmission of cytomegalovirus with valaciclovir prophylaxis exceeds 75.9%. In Monte Carlo analyses, first-trimester universal serologic screening with valaciclovir prophylaxis was estimated to be the cost-effective strategy in 46.8% of runs. CONCLUSION: Universal first-trimester serologic screening with valaciclovir prophylaxis is not the cost-effective strategy for antenatal management of cytomegalovirus under the base case estimates. Although universal screening is cost-effective in certain circumstances when the efficacy of valaciclovir exceeds the base case, that result was not robust to variation of estimates across their reasonable ranges. These data can inform future studies to evaluate screening and treatment to prevent congenital cytomegalovirus.