Combined oral contraceptive (3rd-generation progestogen) Pregnancy: Not indicated for use during pregnancy — if pregnancy occurs the preparation should be withdrawn immediately. Most epidemiological studies have revealed neither an increased risk of birth defects in children born to women who used CHCs before pregnancy nor a teratogenic effect when taken inadvertently in early pregnancy. Consider the increased risk of VTE in the postpartum period when re-starting. Lactation may be influenced (reduced quantity and altered composition of breast milk), so CHCs are generally not recommended until the mother has completely weaned her child.

Ethinylestradiol with desogestrel

Brand names: Marvelon, Mercilon, Gedarel

A combined oral contraceptive pairing ethinylestradiol (an oestrogen) with desogestrel, a third-generation progestogen.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: One tablet (Bimizza 150 microgram/20 microgram tablets) daily for 21 consecutive days

Route: Oral use — take every day at about the same time, with some liquid as needed, in the order shown on the blister pack

Frequency: Once daily for 21 consecutive days, then a 7-day tablet-free interval; each subsequent pack is started after that 7-day tablet-free interval, during which a withdrawal bleed usually occurs (usually starting on day 2-3 after the last tablet)

STARTING — no preceding hormonal contraceptive in the past month: start on day 1 of the natural cycle (first day of menstrual bleeding), no extra precautions needed. If menstruation began 2, 3 or 4 days previously, start on day 5 of the menstrual period with additional contraceptive precautions for the first 7 days of tablet taking. If menstruation began more than 5 days previously, wait until the next menstrual period before starting. SWITCHING — from a 21-day (or 22-day) pill: finish the old pack and take the first tablet the next day, no gap, no additional precautions. From a combined Every Day (28-day) pill: start after the last active tablet (i.e. after 21 or 22 tablets), the next day, no gap, no additional precautions; discard the remaining ED tablets. From a progestogen-only pill: take the first tablet on the first day of the period even if a mini pill has already been taken that day (no additional precautions); if there is no period (e.g. breast-feeding), take the first tablet the day after stopping the mini pill and use additional precautions for the first seven days; discard remaining mini pills. From another combined hormonal contraceptive (COC, vaginal ring or transdermal patch): start preferably the day after the last active tablet of the previous COC, and at the latest the day following its usual tablet-free or placebo interval; for a ring or patch, start preferably on the day of removal and at the latest when the next application would have been due. From a progestogen-only injection, implant or progestogen-releasing IUS: may switch any day (implant/IUS on the day of removal; injectable when the next injection would be due) but use additional contraceptive precautions for the first 7 days of tablet-taking. AFTER PREGNANCY — following first-trimester abortion may start immediately with no additional measures; following delivery (non-breast-feeding) or second-trimester abortion start at day 21 to 28, and if starting later use a barrier method for the first 7 days (exclude pregnancy first if intercourse has already occurred). MISSED TABLETS — if less than 12 hours late, contraceptive protection is not reduced: take the tablet as soon as remembered and take further tablets at the usual time. If more than 12 hours late, contraceptive protection may be reduced: take the last forgotten tablet (the SPC extract is truncated at this point — clinician to confirm the full missed-tablet rules from the SPC). ADDITIONAL PRECAUTIONS — advise no sex, or a cap plus spermicide, or a condom; rhythm methods should not be advised. SKIPPING A PERIOD — start a new pack the day after finishing the current pack (skip the tablet-free days) and continue as usual; slight spotting or breakthrough bleeding may occur but contraceptive protection is not diminished provided no tablets are omitted; the next pack is started after the usual 7 tablet-free days. PAEDIATRIC — no paediatric posology is stated in this SPC section.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Presence or risk of venous thromboembolism — current VTE (on anticoagulants) or history of DVT/PE; known hereditary or acquired predisposition (APC-resistance including Factor V Leiden, antithrombin-III deficiency, protein C deficiency, protein S deficiency); major surgery with prolonged immobilisation; high risk of VTE due to multiple risk factors
Presence or risk of arterial thromboembolism — current or previous ATE (e.g. myocardial infarction) or prodromal condition (e.g. angina pectoris); cerebrovascular disease (current or previous stroke, or TIA); known hereditary or acquired predisposition (hyperhomocysteinaemia, antiphospholipid antibodies); history of migraine with focal neurological symptoms; high risk of ATE due to multiple risk factors or one serious risk factor such as diabetes mellitus with vascular symptoms, severe hypertension or severe dyslipoproteinaemia
Pancreatitis or a history thereof if associated with severe hypertriglyceridaemia
Presence or history of severe hepatic disease as long as liver function values have not returned to normal
Presence or history of liver tumours (benign or malignant)
Known or suspected estrogen-dependent tumours
Endometrial hyperplasia
Undiagnosed vaginal bleeding
Known or suspected pregnancy
Hypersensitivity to the active substances or to any of the excipients
Concomitant use with medicinal products containing ombitasvir/paritaprevir/ritonavir and dasabuvir, glecaprevir/pibrentasvir, or sofosbuvir/velpatasvir/voxilaprevir

Side effects

Headache (common); migraine (uncommon)
Nausea, abdominal pain (common); vomiting, diarrhoea (uncommon)
Breast pain, breast tenderness (common); breast enlargement (uncommon); vaginal discharge, breast discharge (rare)
Depressed mood, mood altered (common); libido decreased (uncommon)
Weight increased (common), weight decreased (uncommon); fluid retention (common)
Venous thromboembolism and arterial thromboembolism (incidence in observational cohort studies of at least 1/10,000 to 1/1,000 women-years) — an increased risk of arterial and venous thrombotic and thromboembolic events including myocardial infarction, stroke, transient ischaemic attack, venous thrombosis and pulmonary embolism has been observed in women using CHCs
Changes in vaginal bleeding patterns (frequency, intensity or duration), especially during the first months of use

Interactions

Medicinal products containing ombitasvir/paritaprevir/ritonavir and dasabuvir, glecaprevir/pibrentasvir, or sofosbuvir/velpatasvir/voxilaprevir — concomitant use is contraindicated (stated in SPC §4.3 cross-referring to §4.5; the full §4.5 interaction section was not captured in this bundle — clinician to review it)

Clinical monograph

How it works

Ovulation is inhibited through suppression of the hypothalamic-pituitary axis, supplemented by progestogen-induced thickening of cervical mucus and endometrial changes that impair implantation.

Prescribing in practice

Desogestrel-containing pills carry a higher VTE risk than those containing levonorgestrel, norethisterone or norgestimate, so confirm the woman is informed of and accepts this when choosing the product.
Screen against UKMEC for thrombotic, cardiovascular, migraine-with-aura and other contraindications before prescribing.
Efficacy is reduced by enzyme-inducing drugs and by significant vomiting or diarrhoea; advise on missed-pill rules.

Monitoring

Check blood pressure and reassess VTE and cardiovascular risk at initiation and at regular reviews.

Counselling the patient

Be aware this pill carries a slightly higher clot risk than some alternatives.
Take at the same time each day and follow missed-pill advice.
Seek urgent help for leg swelling, chest pain, breathlessness or sudden severe headache.

Evidence & guidelines

MHRA reviews and UKMEC document the relative VTE risk differences between progestogen generations in combined pills.

Reference: FSRH CHC guideline; UKMEC; MHRA Drug Safety Update; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Ethinylestradiol with gestodene · Combined oral contraceptive (3rd-generation progestogen)

Pathways