Objectives: To prove that point mutations in exons 4 and 5 (V660L and H770H) of the progesterone receptor gene are risk factors for preterm delivery. Study design: A retrospective study of genetic variations in the progesterone receptor gene that may lead to preterm birth. Participants and methods: The study was conducted on postnatal mothers and their children at the Clinic for Gynaecology and Obstetrics of the Clinical Hospital Center Osijek. A total of 200 samples were collected. A 100 of them constituted control groups consisting of term mothers (n = 50) who gave birth spontaneously and their children (n = 50). The other 100 samples comprised the study groups consisting of preterm mothers (n = 50) and their children (n = 50). Preterm births were divided into the following groups: early preterm births (before 28th gestational week), moderate preterm births (28th - 32nd gestational weeks) and late preterm births (32nd - 37th gestational weeks). The first step in the study was DNA isolation using a commercial NucleoSpin Blood kit from maternal venous blood and from children blood samples from the umbilical cord. The second step was DNA genotyping using real-time PCR according to the TaqMan SNP Genotyping Assay protocol on an Applied Biosystems device. Descriptive statistical processing was performed. The obtained results were statistically processed in MedCalc (version 16.2.0., MedCalc Software bvba, Ostend, Belgium). Results: The tested V660L and H770H mutations have no statistical significance for premature birth. Also, age, BMI and p4 have no statistical significance. Conclusion: The study showed that the V660L and H770H mutations are not risk factors for preterm birth in the study population. Age and BMI are also not risk factors for premature birth.