Oral contraception and hormone replacement therapy: management of their thromboembolic risk in the perioperative period

Objectives

Many women scheduled for surgery are using either oral contraception (OC) or hormone replacement therapy (HRT). These two treatments are associated with a significant albeit moderately increased risk of venous thromboembolic events which might increase the risk associated with surgery.

Data source

Record of French and English references from Medline^® database.

Data extraction

Data were selected including prospective and retrospective studies, reviews, and case reports.

Data synthesis

Thromboembolism induced by these two pharmacologic classes is similar and close to that produced by pregnancy. The increased risk is usually small, especially after the first year of administration of either class of drug, for progestogen-only contraception drugs and for transdermal HRT. The increased risk should be compared with the occurrence of undesired pregnancy after discontinuation of OC or the occurrence of climateric symptoms after discontinuation of HRT. Maintaining OC during the perioperative period is legitimate and strengthening prophylaxis is justified during the first year of combined OC administration. Stressful climateric symptoms can lead to maintain HRT and strengthening prophylaxis is justified during the first year of oral HRT. Transdermal HRT may not need to be stopped and probably does not require any additional antithrombotic measure.

Conclusion

The increased thromboembolic risk is to be compared with the risks of stopping either treatment. In most cases, these two treatments can be maintained and antithrombotic prophylaxis is moderately strengthened in particular cases.