The presence of unprotected sex activity in women living with type 1 diabetes (T1D) who have insufficient glycemic control should be considered as a specific risky behavior. To evaluate risky behaviors, including unprotected sexual activity, sources of information and knowledge related to reproductive health in adolescents and young adult women with T1D (PwT1D) compared to a group of adolescents and young adult women without diabetes (Comparison group). PwT1D and the Comparison group completed a questionnaire with validated measures that assessed reproductive health. PwT1D (n = 115, age = 17.7 ± 3.2 years) and Comparison group (n = 386, age = 18.3 ± 2.9) were recruited. The proportion of women reporting having sex without any contraceptive was similar in both groups (57.1% and 50%, in PwT1D and Comparison group, respectively). The use of non‐effective contraceptive was reported in 63.2% and 63.6% of the PwT1D and Comparison group, respectively. Among PwT1D, parents, formal sex education, and friends were the primary source of information on reproductive health. Low levels of knowledge about diabetes and pregnancy were observed in PwT1D. HbA1c level was associated with having at least one sexual activity without any contraception (OR = 1.63, p = 0.039). PwT1D have similar rates of risky behaviors compared to a Comparison group. Sexual risky behaviors should be especially considered in PwT1D with glycemic control above the optimal level. Parents are an important source of reproductive health information for PwT1D. Use of effective contraception should be reinforced in sexually active PwT1D.