Marvelon Special Precautions

Medical Examination/Consultation: Prior to the initiation or reinstitution of Marvelon, a complete medical history (including family history) should be taken and pregnancy must be ruled out. Blood pressure should be measured and a physical examination should be performed, guided by the contraindications (see Contraindications) and warnings (see Warnings). It is important to draw a woman's attention to the information on venous and arterial thrombosis, including the risk of Marvelon compared with other CHCs, the symptoms of VTE and ATE, the known risk factors and what to do in the event of a suspected thrombosis.
The woman should also be instructed to carefully read the user leaflet and to adhere to the advice given. The frequency and nature of examinations should be based on established practice guidelines and be adapted to the individual woman.
Women should be advised that oral contraceptives do not protect against HIV infections (AIDS) and other sexually transmissible diseases.
Reduced efficacy: The efficacy of Marvelon may be reduced in the event of for example missed tablets (see Management of missed tablets under Dosage & Administration), gastrointestinal disturbances (see Advice in the case of gastrointestinal disturbances under Dosage & Administration) or concomitant medication that decrease the plasma concentration of ethinylestradiol and/or etonogestrel, the active metabolite of desogestrel (see Interactions).
Herbal preparations containing St. John's wort (Hypericum perforatum) should not be used while taking Marvelon, since this can result in decreased plasma concentrations and reduced clinical effects of Marvelon (see Interactions).
Reduced cycle control: With all COCs, irregular bleeding (spotting or breakthrough bleeding) may occur, especially during the first months of use. Therefore, the evaluation of any irregular bleeding is only meaningful after an adaptation interval of about three cycles.
If bleeding irregularities persist or occur after previously regular cycles, then non-hormonal causes should be considered and adequate diagnostic measures are indicated to exclude malignancy or pregnancy. These may include curettage.
In some women withdrawal bleeding may not occur during the tablet-free interval. If the COC has been taken according to the directions described in Dosage & Administration, it is unlikely that the woman is pregnant. However, if the COC has not been taken according to these directions prior to the first missed withdrawal bleed or if two withdrawal bleeds are missed, pregnancy must be ruled out before COC use is continued.
Effects on ability to drive and use machines: No effects on the ability to drive and use machines have been observed.