In order to determine the effect of perioperative blood transfusions (BT) on the recurrence of Crohn's disease after primary surgery we reviewed the medical histories of 148 patients with Crohn's disease, 62 males and 86 females (49 non-parous and 37 parous females). Eighty-seven patients received perioperative BT. Overall, perioperative BT showed no effect on recurrence. Patients with Crohn's disease limited to the ileum had a better prognosis with regard to recurrence than patients with Crohn's disease located in the colon or located in both ileum and colon, but this was not significant. Perioperative transfusion seemed to protect against recurrent disease after colon resection, which might be explained by the fact that colon resections, which often necessitate perioperative BT, generally result in a shorter bowel segment at risk for recurrent disease. Overall, parous females showed a worse prognosis than non-parous females and males (p = 0.022). Transfusions had a beneficial effect in parous females (p = 0.068) and after correction for type of operation this beneficial effect was significant (p = 0.026). After perioperative BT parous females had a similar prognosis regarding recurrent Crohn's disease to that of non-parous females and males.