Objective Evaluate the effect of fathers participation in the Preemie Prep for Parents (P3) program on maternal learning and fathers preterm birth knowledge. Methods Mothers with preterm birth predisposing medical condition(s) enrolled with or without the father of the baby and were randomized to the P3 intervention (text-messages linking to animated videos) or control (patient education webpages). Parent Prematurity Knowledge Questionnaire assessed knowledge, including unmarried fathers legal neonatal decision-making ability. Results 104 mothers reported living with the father of the baby; 50 participated with the father and 54 participated alone. In the P3 group, mothers participating with the father (n=33) had greater knowledge than mothers participating alone (n=21), 85% correct responses vs. 76%, p=0.033. However, there was no difference in knowledge among the control mothers, 67% vs. 60%, p=0.068. P3 fathers (n=33) knowledge scores were not different than control fathers (n=17), 77% vs. 68%, p=0.054. Parents who viewed the video on fathers rights (n=58) were more likely than those who did not (n=96) to know unmarried fathers legal inability to decide neonatal treatments, 84% vs. 41%, p<0.001. Conclusions Among opposite-sex cohabitating couples, fathers participation in the P3 program enhanced maternal learning. Practice Implications The potential of the P3 program to educate fathers may benefit high-risk pregnancies.