A woman develops ongoing haemorrhage during an emergency caesarean section for uterine atony. After 3 units of red blood cells and 2 units of fresh frozen plasma, the bleeding is slowing but continues. Her fibrinogen concentration is 1.4 g/L (reference range 2.0–4.0), platelet count is 118 × 10⁹/L (150–400), and prothrombin time is only mildly prolonged. Which one of the following blood products should be given now?