The study introduced a "cost-to-baby" metric, calculating the financial burden of achieving a live birth against median after-tax household income. By accounting for subsidies and tax benefits, the researchers found that affordability varies drastically across the globe. Gross costs ranged from 66% of median income in Israel to over 830% in parts of Africa, a 12-fold disparity that directly dictates the success of fertility programs.

Nations where net out-of-pocket costs remain below 50% of median household income, such as South Korea, Spain, and Japan, report that nearly 10% or more of all births occur through ART. In sharp contrast, regions where costs balloon to two or three times the annual median income, including Brazil and India, see ART-assisted births drop to as low as 0.2%. Lead author Dr. Stephanie Kuku of Conceivable Life Sciences noted that the model explains up to 84% of the variation in global utilization. The 50% threshold serves as a concrete benchmark for policymakers, proving that financial accessibility is the primary driver of fertility outcomes rather than medical infrastructure alone.