Weight treatment, contraception and planning a pregnancy: what to know

Social media carries stories of unexpected pregnancies during medical weight treatment. A plausible explanation: excess weight can disrupt ovulation, for example with PCOS. As weight falls, cycles may normalise and fertility can rise.

It's not an effect to rely on in either direction, and robust data are still scarce.

Vomiting and severe diarrhoea can affect how well the pill is absorbed, whatever the treatment. That matters especially during titration, when gut complaints are more common.

For one of the active substances, the product information also states that the effect of oral contraceptives may be reduced in certain phases of treatment and recommends an additional or different method then. Whether this applies to your medicine is in your package leaflet; if in doubt, ask your prescribing doctor. Ask your gynaecologist which method suits you during treatment. Whether and how a switch or a dose change happens is decided by the doctor in each individual case.

If you want to become pregnant, say so openly when treatment is prescribed. Treatment is then stopped beforehand. How long before depends on the medicine and is in the product information.

If you become pregnant during treatment, stop the medicine and contact a doctor promptly. These weight-management medicines are also not used while breastfeeding.

This article is for information and does not replace medical advice. It is not a diagnosis, a prescription or a promise of any result.

Whether treatment is suitable for you is clarified through our medical questionnaire. A doctor reviews your details and decides on the prescription. If you have severe side effects, a doctor is available to you free of charge at any time.

For acute or severe symptoms, contact your GP, the out-of-hours medical service (116117) or, in an emergency, 112.

Whether and how a switch or a dose change happens is decided by the doctor in each individual case.