This was a cross-sectional, retrospective study on the influence of seasonality on the frequency and prognosis of HRP at the Gabriel Touré University Hospital from January 1, 2020 to December 31, 2022, i.e. a duration of 3 years. This study allowed us to identify over a period of 3 years, 595 cases of HRP out of a total of 9447 deliveries, i.e. a frequency of 6.2%, with an increase in cases of HRP during the rainy season to 43.02%. The main reason for admission was metrorrhagia/pregnancy 83.03%. We found at the end of our study that the rainy season is a risk factor for the occurrence of HRP with a frequency of 43.02% during the rainy season, followed by the hot season at 30.25% and the cold season at 26.72%. Sher's HRP grade IIIA was the most diagnosed type at 76.63% and especially during the rainy season, with more complications of anemia and hemorrhagic shock at 73.61% and 14.96%. Caesarean section was performed in 80.2% of cases. We recorded 42 HRP-related maternal deaths or 7.05%, with a higher number during the rainy season at 59.52%. The fetal prognosis was poor with 89.06% fetal mortality. Retroplacental hematoma is a relatively common obstetric pathology. The rainy season would have an impact on its occurrence, but also on the maternal and fetal prognosis in our context.