PURPOSE: This study aimed to identify factors affecting transgender adolescents' and young adults' (AYA) decisions to pursue fertility preservation (FP). METHODS: Participants completed a semistructured interview between December 2016 and June 2017 to inform improvements in fertility counseling and the development of a fertility decision aid targeted to transgender youth. Interviews included open-ended questions within the following domains: (1) gender-affirming medical care received, (2) knowledge of gender-affirming hormone effects on fertility and FP options, (3) FP decision-making, and (4) how, when, and what information AYA prefer to receive regarding FP. The interviews were analyzed thematically. RESULTS: Eighteen transgender AYA (ages 15-24) participated (60% participation rate). The majority was White (61%) and assigned female at birth (67%). Half received specialized FP counseling (50%). Few of the transgender AYA pursued FP (33%). Five key themes reflecting factors affecting transgender AYA's FP decision-making were identified: (1) future parenthood desires, (2) individual experiences of gender dysphoria, (3) family values around biological parenthood, (4) financial considerations, and (5) fertility information provision. CONCLUSIONS: Transgender AYA consider numerous factors in deciding whether to pursue FP. Although individual desires for and family values around biological parenthood influenced whether AYA pursued specialized FP counseling, individual experiences of gender dysphoria and costs of FP were barriers. AYA also identified shortcomings in fertility counseling with providers, highlighting the need to establish standardized counseling protocols and develop patient decision aids.