Abstract In obstetrical practice, the best prevention strategy for pregnant women aged >35 years without known thrombosis risk factors who underwent elective caesarean delivery (CD) is controversial. We performed an observational-longitudinal cohort study on pregnant women aged >35 years who delivered at term by elective caesarean section after a physiological single pregnancy to evaluate the role of maternal age in the decision-making process of whether or not to perform low-molecular-weight heparin (LMWH) prophylaxis during the post-partum period after elective CD in healthy women with unknown inherited thrombophilia status. During the 6 post-partum weeks, we followed two groups: GROUP-A (349 women treated for 7 days with low-molecular-weight heparin) and GROUP-B (180 women not treated with LMWH treatment). The outcomes were as follows: onset of thromboembolic events during the post-partum period; non-obstetrical-linked maternal haemorrhage; blood transfusion; re-laparotomy; detection of a surgical site haematoma; length of hospitalisation; and treatment suspension because of decreased platelet count. Except for the parity number, the two groups were homogeneous with regard to general features. In both the groups, we reported no cases of thromboembolic events during the follow-up period. Maternal haemorrhage requiring transfusion occurred in 16 women in GROUP-A and none in GROUP-B. Among the GROUP-A women, 11 demonstrated a surgical site haematoma and 4 required re-laparotomy. No cases of treatment suspension were reported. Pneumatic compression stockings represent a better, low cost and safe way to prevent post-partum venous thromboembolic episodes after elective caesarean section in an unscreened population. Pharmacological prophylaxis after elective caesarean section should be performed only in case of clear and known adjunctive risk factors, independent of maternal age.