Combined Hormonal Contraceptives


 

Ethinylestradiol with cyproterone acetate, Ethinylestradiol with desogestrel, Ethinylestradiol with drospirenone, Ethinylestradiol with etonogestrel, Ethinylestradiol with gestodene, Ethinylestradiol with levonorgestrel, Ethinylestradiol with norelgestromin, Ethinylestradiol with norethisterone, Ethinylestradiol with norgestimate, Estradiol with dienogest, Estradiol with nomegestrol, Mestranol with norethisterone


  Issues for Surgery


Risk of contraceptive failure and pregnancy (potentially leading to cancellation of surgery) if discontinued preoperatively.

Risk of venous thromboembolism (VTE) if continued.


  Advice in the Perioperative period


Elective Surgery

Minor Surgery 
Continue if risk of prolonged immobilisation is low1, 2.

Major Surgery
Preferably discontinue 4 weeks before major elective surgery, surgery to the legs or surgery that involves prolonged immobilisation of a lower limb1, 2.

Consider other risk factors that the patient may have that further increase the risk of VTE e.g. age, weight, previous history of VTE.

If it is deemed appropriate for the patient to discontinue their contraception, then they MUST be given advice on alternative contraception and pregnancy must be excluded on admission

Emergency Surgery

Ensure adequate thromboprophylaxis to reduce risk of VTE.

If prolonged immobilisation anticipated consider discontinuing on admission.

Perioperative Considerations

If sugammadex is administered in theatre see post-operative advice under Interaction(s) with Common Anaesthetic Agents.

Post-operative Advice

If stopped pre-operatively restart at the first menses occurring at least 2 weeks after full mobilisation.


  Interaction(s) with Common Anaesthetic Agents


Sugammadex

Administration of a single bolus dose of sugammadex is predicted to cause a 34% decrease in progestogen exposure; the effect on oestrogen will be lower. This predicted pharmacokinetic reaction has not been proven clinically however it is recommended that users of oral contraceptives follow the missed dose advice in the package leaflet and that users of non-oral hormonal contraceptives use an additional non-hormonal contraceptive method for the next 7 days3, 4.


  Interaction(s) with other Common Medicines used in the Perioperative Period


Etoricoxib

Etoricoxib slightly increases the exposure to combined hormonal contraceptives2, 3.


  Further Information


Risk of VTE

Patients taking combined hormonal contraceptives are at increased risk of venous thromboembolism (VTE) compared with non-users1, 2. The risk is thought to be greatest in the first year of treatment and also when restarting after a gap of more than four weeks1. The incidence of VTE varies depending on both the oestrogen dose and the type of progesterone1. Products that contain levonorgestrel, norgestimate or norethisterone are associated with the lowest risk of VTE whereas products containing third generation progestogens have a higher risk of VTE1 (see figure 1). Ethinylestradiol with cyproterone acetate (Dianette®) is estimated to confer a similar VTE risk to third generation progestogens5, 6. Products with 20microgram oestrogen doses were associated with a lower incidence of VTE than products with 30-40microgram oestrogen doses in a population based cohort study1.

VTE estimates in the literature for the combined transdermal patch (Evra®) and combined vaginal ring (NuvaRing®) are conflicting but appear to be higher than the oral route (approx. 6-12 cases per 10,000 women per year of use)1, 7, 8.

The incidence of VTE in users of oestrogen containing contraception remains considerably lower than in pregnant patients and postpartum patients1.

Figure 1: Estimated incidence of VTE per 10,000 women per year of use for various combined hormonal contraceptives1, 2.

Alternative Contraception

Progesterone-only contraceptives are recommended as an alternative to combined hormonal contraceptives for patients before major elective surgery, before surgery to the lower limbs or before surgery that involves prolonged immobilisation of a lower limb1, 2. Consult the product literature for advice about switching.


  References


  1. Faculty of Sexual and Reproductive Healthcare. Clinical Guidance Combined hormonal contraception. Clinical Effectiveness Unit. January 2019 (updated February 2019).  https://www.fsrh.org [Accessed on 11th May 2019]
  2. Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. http://www.medicinescomplete.com [Accessed on 11th May 2019]
  3. Baxter K, Preston CL (eds), Stockley’s Drug Interactions (online) London: Pharmaceutical Press. http://www.medicinescomplete.com  [Accessed on 10th May 2019
  4. Summary of Product Characteristics - Bridion® (sugammadex). Merck Sharp & Dohme Limited.  Accessed via www.medicines.org.uk 10/05/2019 [date of revision of the text March 2019]
  5. Summary of Product Characteristics - Dianette® (ethinylestradiol with cyproterone acetate). Bayer plc.  Accessed via www.medicines.org.uk 04/06/2019 [date of revision of the text December 2018]
  6. Vinogradova Y. Coupland C & Hippisley-Cox J. Use of combined oral contraceptives and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases.  BMJ. 2015; 350:h2135.
  7. Summary of Product Characteristics – Evra transdermal patch® (ethinylestradiol with norelgestromin). Janssen-Cilag Ltd.  Accessed via www.medicines.org.uk 04/06/2019 [date of revision of the text November 2018]
  8. Summary of Product Characteristics - NuvaRing® (ethinylestradiol with etonorgestrel). Merck Sharp & Dohme Limited.  Accessed via www.medicines.org.uk 04/06/2019 [date of revision of the text March 2019]