Study goals: To demonstrate which factors contribute to the success of medically assisted reproduction (MAR) methods among couples in treatment in the Republic of Croatia. Study design: A cross-sectional study Participants and methods: The study consisted of 216 participants, 2 of whom are male. All the participants, 169 of whom were women who had already given birth either naturally or who had conceived through MAR, undergo fertility treatment in the Republic of Croatia. The study was conducted online by means of a 39-item questionnaire in January and February 2022. It was carried out in closed groups of couples undergoing the fertility treatment both in private and public medical institutions. The statistical analysis was conducted by using MedCalc software package. Results: A statistically significant difference between undergoing fertility treatment in private or public clinics/hospitals has not been observed with regard to pregnancy rate. The most frequent reason for an unsuccessful fertility treatment cycle is attributable to a higher women’s age. A significantly higher pregnancy rates appear in participants who had 5 or more embryo transfer procedures, with more than 10 egg cells received per aspiration. Vaginal bleeding is given as the most frequent complication, whereas the partner is perceived as the greatest emotional support during the procedure. Additionally, the majority of the participants, i.e. 75% of them, believe MAR procedures to be extremely stressful. Conclusion: According to the obtained results, the following methods or procedures do not demonstrate a statistically significant effect on the implantation rate: the use of EmbryoGlue or alternative methods, moderate or strict bed rest as opposed to continuing normal daily routine, dietary changes and gynecologic surgeries and/or procedures. On the other hand, general anesthesia during the aspiration of egg cells, lack of stress and an experienced medical doctor have a positive impact on the MAR procedure outcome. Moreover, in vitro fertilization (IVF) is the most successful method of infertility treatment. Additionally, an unsuccessful fertility SUMMARY 49 treatment has a negative impact on both female and male mental health and may undermine the couple’s quality of life.