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Combined Hormonal Contraceptive (Oestrogen + Progestogen) Pregnancy: UK SPC section 4.6: 'Microgynon 30 is not indicated during pregnancy. If pregnancy occurs during treatment with Microgynon 30, further intake must be stopped. However, extensive epidemiological studies have revealed neither an increased risk of birth defects in children born to women who used COCs prior to pregnancy, nor a teratogenic effect when COCs were taken inadvertently during early pregnancy. The increased risk of VTE during the postpartum period should be considered when re-starting Microgynon 30. The use of Microgynon 30 during lactation may lead to a reduction in the volume of milk produced and to a change in its composition. Minute amounts of the active substances are excreted with the milk. These amounts may affect the child particularly in the first 6 weeks post-partum. Mothers who are breast-feeding may be advised instead to use another method of contraception.'

Combined Oral Contraceptive Pill (COCP)

Brand names: Microgynon 30, Rigevidon, Cilest, Yasmin, Marvelon, Gedarel

The combined oral contraceptive pill contains an oestrogen and a progestogen and is used for contraception and for menstrual cycle control.

Adult dose

Dose: MICROGYNON 30 TABLETS ONLY (each tablet contains levonorgestrel 150 micrograms and ethinylestradiol 30 micrograms) - oral contraception: first treatment cycle, 1 tablet daily for 21 days, starting on the first day of the menstrual cycle (contraceptive protection begins immediately). Subsequent cycles: tablet-taking from the next pack is continued after a 7-day tablet-free interval, beginning on the same day of the week as the first pack.
Route: Oral (tablets taken in the order directed on the blister package, with some liquid if necessary)
Frequency: One tablet daily at about the same time every day for 21 days, then a 7-day tablet-free interval
CLASS PAGE - THIS CARD DOSES ONE PRODUCT ONLY. The pinned UK SPC is MICROGYNON 30 TABLETS (Bayer plc), a 21-tablet regimen (1 tablet daily for 21 days, then 7 tablet-free days). Other combined oral contraceptives, including the other brands named on this page, have their own SPCs, differ in composition and regimen, and are NOT covered. Extended or continuous regimens and the 28-day (Every Day) presentation are not described in this SPC and are not given. STRENGTH (section 2): levonorgestrel 150 micrograms and ethinylestradiol 30 micrograms per tablet. Section 4.1: 'Oral contraception and the recognised gynaecological indications for such oestrogen-progesterone combinations. The decision to prescribe Microgynon 30 should take into consideration the individual woman's current risk factors, particularly those for venous thromboembolism (VTE), and how the risk of VTE with Microgynon 30 compares with other combined hormonal contraceptives (CHCs).' VERBATIM section 4.2: 'Tablets must be taken orally in the order directed on the blister package at about the same time every day, with some liquid if necessary. First treatment cycle: 1 tablet daily for 21 days, starting on the first day of the menstrual cycle. Contraceptive protection begins immediately. Subsequent cycles: Tablet-taking from the next pack of Microgynon 30 is continued after a 7-day tablet-free interval, beginning on the same day of the week as the first pack. A withdrawal bleed usually occurs during the tablet-free interval.' CHANGING FROM (section 4.2): a 21-day combined oral contraceptive - take the first tablet on the first day immediately after the end of the previous course, no additional precautions; a combined Every Day pill (28-day tablets) - start after the last active tablet of that pack, first tablet the next day, no additional precautions; a progestogen-only pill - take the first tablet on the first day of bleeding, even if a POP has already been taken that day, no additional precautions, and discard the remaining progestogen-only pills. POST-PARTUM AND POST-ABORTUM (section 4.2): after pregnancy, oral contraception can be started 21 days after a vaginal delivery, provided the patient is fully ambulant and there are no puerperal complications, with additional contraceptive precautions for the first 7 days of tablet taking; another method should be used between childbirth and the first course because the first post-partum ovulation may precede the first bleeding; after a first-trimester abortion it may be started immediately with no additional precautions. MISSED OR DELAYED TABLETS (section 4.2): 'A single delayed tablet should be taken as soon as possible, and if this can be done within 12 hours of the correct time, contraceptive protection is maintained. With longer delays, additional contraception is needed. Only the most recently delayed tablet should be taken, earlier missed tablets being omitted, and additional non-hormonal methods of contraception (except the rhythm or temperature methods) should be used for the next 7 days, while the next 7 tablets are being taken. Additionally, therefore, if tablet(s) have been missed during the last 7 days of a pack, there should be no break before the next pack is started. In this situation, a withdrawal bleed should not be expected until the end of the second pack.' If there is no withdrawal bleed in the tablet-free interval following the end of the second pack, the possibility of pregnancy must be ruled out before starting the next pack. VOMITING OR DIARRHOEA (section 4.2): 'Vomiting or diarrhoea may reduce the efficacy of oral contraceptives by preventing full absorption.' The SPC sentence that gives the time window after taking a tablet is garbled in the source text, so that rule is NOT reproduced here - read the SPC itself for it. What is clear: additional non-hormonal methods of contraception (except the rhythm or temperature methods) should be used during the gastro-intestinal upset and for 7 days following it; if those 7 days overrun the end of a pack the next pack should be started without a break; other methods should be considered if the disorder is likely to be prolonged. PAEDIATRIC AND ELDERLY (section 4.2): 'Children: Not applicable. Elderly: Not applicable.' No paediatric dose. NO MAXIMUM DOSE applies (one tablet daily). Some sections of the product information we used were incomplete — check the full SPC. Text came from a PDF and has odd spacing in places.

Dose adjustments

Renal

The UK SPC gives no dose adjustment for renal impairment. Section 4.8 lists renal dysfunction among the conditions reported to deteriorate with pregnancy or previous COC use.

Hepatic

UK SPC section 4.3: presence or history of severe hepatic disease (e.g. active viral hepatitis and severe cirrhosis), as long as liver function values have not returned to normal, and presence or history of liver tumours (benign or malignant), are contraindications. No dose adjustment figure is given.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Combined hormonal contraceptives should not be used in the conditions below; if any appears for the first time during use, stop the product immediately (section 4.3)
  • Presence or risk of venous thromboembolism: current VTE (on anticoagulants) or history of VTE (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; a high risk of VTE due to multiple risk factors (section 4.3)
  • Presence or risk of arterial thromboembolism: current or history of arterial thromboembolism (e.g. myocardial infarction) or prodromal condition (e.g. angina pectoris); current or history of stroke or prodromal condition (e.g. TIA); known hereditary or acquired predisposition (hyperhomocysteinaemia, anti-phospholipid antibodies - anticardiolipin antibodies, lupus anticoagulant); history of migraine with focal neurological symptoms (section 4.3)
  • High risk of arterial thromboembolism due to multiple risk factors or one serious risk factor: diabetes mellitus with vascular symptoms, severe hypertension, severe dyslipoproteinaemia (section 4.3)
  • Presence or history of severe hepatic disease (e.g. active viral hepatitis, severe cirrhosis) until liver function values have returned to normal; presence or history of liver tumours (benign or malignant) (section 4.3)
  • Current or history of breast cancer (section 4.3)
  • Hypersensitivity to the active substance(s) or to any of the excipients (section 4.3)
  • Concomitant use with medicinal products containing ombitasvir/paritaprevir/ritonavir and dasabuvir, glecaprevir/pibrentasvir, or sofosbuvir/velpatasvir/voxilaprevir (sections 4.3, 4.5)
  • Not indicated during pregnancy: stop if pregnancy occurs (section 4.6)

Side effects

  • Most commonly reported (in 1% or more of users, section 4.8): nausea, abdominal pain, increased weight, headache, depressed mood, altered mood, breast pain, breast tenderness
  • Serious adverse reactions are arterial and venous thromboembolism, including myocardial infarction, stroke, transient ischaemic attack, venous thrombosis and pulmonary embolism; hypertension and liver tumours (benign and malignant) are also reported with COCs (sections 4.4, 4.8)
  • The frequency of diagnosis of breast cancer is very slightly increased among COC users; because breast cancer is rare under 40 years of age the excess number is small in relation to the overall risk; causation with COC use is unknown (section 4.8)
  • Other reactions listed in the section 4.8 table (the Common/Uncommon/Rare columns are not recoverable from the PDF extraction, so no frequency is stated): contact lens intolerance; vomiting, diarrhoea; Crohn's disease, ulcerative colitis; hypersensitivity, exacerbation of symptoms of hereditary and acquired angioedema; weight decreased; fluid retention; hypertriglyceridaemia; migraine, exacerbation of chorea; liver function disturbances; libido decreased, libido increased
  • Other reactions listed in the section 4.8 table (frequency not stated, as above): breast hypertrophy, vaginal discharge, breast discharge; reduced menstrual flow, spotting, breakthrough bleeding, missed withdrawal bleeding, post-pill amenorrhoea; rash, urticaria, erythema nodosum, erythema multiforme, chloasma
  • Conditions reported to deteriorate with pregnancy or previous COC use: jaundice and/or pruritus related to cholestasis; gallstone formation; systemic lupus erythematosus; herpes gestationis; otosclerosis-related hearing loss; sickle cell anaemia; renal dysfunction; hereditary angioedema; porphyria; cervical cancer (section 4.8; the section is cut off at the source-fetch limit, so this list is partial)

Interactions

  • Enzyme inducers (especially CYP3A4) can increase clearance of sex hormones and lead to breakthrough bleeding and/or contraceptive failure. Short-term treatment: use a barrier method in addition during the concomitant drug and for 28 days after stopping; if that period runs beyond the end of a pack, start the next pack without a break. Long-term therapy with enzyme inducers: use another method of contraception (section 4.5)
  • Anticonvulsants with clinically important interactions: barbiturates (including phenobarbitone), primidone, phenytoin, carbamazepine, oxcarbazepine, topiramate (section 4.5)
  • Griseofulvin and rifampicin; the herbal remedy St John's wort (Hypericum perforatum) (section 4.5)
  • Antiretrovirals ritonavir, nelfinavir, nevirapine; other antiretroviral agents may increase plasma concentration of sex hormones (section 4.5)
  • Strong and moderate CYP3A4 inhibitors such as azole antifungals (itraconazole, voriconazole, fluconazole) and macrolides (erythromycin) can increase plasma concentrations of the oestrogen or the progestin or both (section 4.5)
  • Etoricoxib 60 to 120 mg/day increased plasma ethinylestradiol 1.4 to 1.6-fold when taken with a CHC containing 0.035 mg ethinylestradiol (section 4.5)
  • Oral contraceptives may increase plasma and tissue concentrations of ciclosporin, tizanidine and theophylline, or decrease those of lamotrigine (section 4.5)
  • Contraindicated with ombitasvir/paritaprevir/ritonavir and dasabuvir, glecaprevir/pibrentasvir, sofosbuvir/velpatasvir/voxilaprevir (sections 4.3, 4.5)
  • This interaction list may be incomplete — check the full SPC.

Monitoring

  • Before prescribing, discuss the woman's current risk factors, particularly for VTE, and make sure she understands the VTE risk; the VTE risk is highest in the first ever year of use and may be increased when a CHC is re-started after a break of 4 weeks or more (sections 4.1, 4.4)
  • VTE risk factors listed in section 4.4 include obesity (BMI over 30 kg/m2), prolonged immobilisation or major surgery, positive family history of VTE (refer to a specialist if a hereditary predisposition is suspected), cancer, systemic lupus erythematosus, haemolytic uraemic syndrome, chronic inflammatory bowel disease, sickle cell disease and increasing age, particularly above 35 years; with more than one risk factor the total risk should be considered
  • Before elective surgery or prolonged immobilisation: advisable to discontinue the pill at least four weeks in advance and not resume until two weeks after complete remobilisation; use another method of contraception meanwhile (section 4.4)
  • Symptoms of VTE (unilateral leg swelling or pain, sudden unexplained shortness of breath, sudden coughing, sharp chest pain, rapid or irregular heartbeat) and of vascular occlusion (sudden pain, swelling or blue discoloration of an extremity, loss or blurring of vision): advise urgent medical attention (section 4.4)
  • If there is no withdrawal bleed in the tablet-free interval following the end of the second pack, rule out pregnancy before starting the next pack (section 4.2)
  • If any contraindicating condition or risk factor appears or worsens, the woman should contact her doctor to decide whether to stop (section 4.4)

Clinical monograph

How it works

It primarily inhibits ovulation by suppressing pituitary gonadotrophin release, with additional effects of thickening cervical mucus and altering the endometrium.

Prescribing in practice

  • It carries an increased risk of venous and arterial thromboembolism, so prescribing requires assessment against UK Medical Eligibility Criteria and is avoided where risk factors such as migraine with aura are present.
  • Effectiveness can be reduced by enzyme-inducing drugs and by vomiting or severe diarrhoea, requiring additional precautions.
  • Blood pressure should be checked before starting and contraception reviewed if new risk factors develop.

Monitoring

Monitor blood pressure and periodically reassess cardiovascular and thrombotic risk factors and the chosen method.

Counselling the patient

  • Seek urgent help for symptoms of a clot such as calf swelling, chest pain or breathlessness.
  • Use extra precautions if you miss pills, vomit or have severe diarrhoea, or start an interacting medicine.
  • Report new or worsening migraine, especially with aura, as this may mean the pill is no longer suitable.

Evidence & guidelines

UK Medical Eligibility Criteria for Contraceptive Use guide safe prescribing and contraindications for combined hormonal contraception.

Reference: FSRH Guidelines on Combined Hormonal Contraception 2019 (updated 2023); UKMEC 2016; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. 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).

Related

Curated clinical cross-links plus same-class fallbacks.

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