Introduction. In Poland, vaccinations take place in medical entities and are run by doctors, nurses and midwives. Persons who have stayed within the territory of the Republic of Poland for over 3 months are obliged to undergo protective vaccinations against infectious diseases in accordance with the applicable Protective Vaccination Program. Aim. The aim of the study was to identify factors determining the implementation of recommended immunization in children under 2 years of age. Material and methods. The study involved 300 respondents (parents of children up to two years old), 91% women and 9% men. The research was carried out in pediatric clinics and a family doctor in the city of Szczecin. The research was based on an author’s questionnaire containing sociodemographic data and questions about immunization. Results. Over 78.67% of parents surveyed reported that their child is vaccinated in accordance with the preventive vaccination calendar. It was observed that the number of children held did not have a significant impact on the implementation of immunization. According to the vast majority (82%) of parents, non-compulsory vaccinations, not refunded, should be included in the vaccination calendar. Over half (61.67%) of respondents declare that they do not use compulsory vaccines, only buy multi-component vaccines, justified their decision by a smaller amount of additional preservatives. Conclusions. 1) Parents are eagerly expanding the mandatory immunization calendar for vaccinations recommended. 2) Parents demonstrate great knowledge of the benefits of using preventive vaccinations. 3) The occurrence of post-vaccination reactions in a child determines the parents’ decision about the preventive measures taken in the field of mandatory and recommended vaccinations.

Key words: protective vaccinations, vaccination reactions, parents, knowledge.