The study analyzed risk factors for aggressive posterior retinopathy of prematurity (AP-ROP) in 350 infants treated for ROP in the German Retina.net registry from 2011–2020, with AP-ROP diagnosed in 21 infants (6%), representing 38 eyes (5.5%). Infants with AP-ROP had significantly lower gestational age (24.3 vs. 25.4 weeks; p=0.0001) and lower birth weight (595 vs. 697 g; p=0.0262) than controls (N=329). Treatment of AP-ROP took place at a significantly lower postmenstrual and postnatal age, predominantly with intravitreal anti-VEGF therapy (79% of eyes) versus laser photocoagulation in controls (60%). Eyes with AP-ROP required repeated treatments more frequently (39% vs. 15%; p=0.0002). At approximately 12 months postnatal age, 12 of 15 eyes with AP-ROP had central fixation, 6 of 15 showed strabismus, and the median spherical equivalent was 0.0 dpt (IQR: -2.6 to 1.0 dpt). One child had a complete and one a partial retinal detachment in one eye. The study confirmed risk factors such as low gestational age and birth weight, but did not observe male gender or some comorbidities.