Medical devices are products or equipment intended for a medical purpose. In the European Union (EU) they must undergo a conformity assessment to demonstrate they meet legal requirements to ensure they are safe and perform as intended. They are regulated at EU Member State level, but the European Medicines Agency (EMA) is involved in the regulatory process.

Manufacturers can place a CE (Conformité Européenne) mark on a medical device once it has passed a conformity assessment.

The conformity assessment usually involves an audit of the manufacturer's quality system and, depending on the type of device, a review of technical documentation from the manufacturer on the safety and performance of the device.

EU Member States designate accredited notified bodies to conduct conformity assessments. For certain high-risk devices, notified bodies shall request the opinion of specific expert panels before issuing the certificate of conformity. These expert panels benefit from EMA's technical and scientific support. 

In some other cases, the notified body must seek a scientific opinion from EMA before issuing a CE certificate.

EMA has distinct regulatory responsibilities per category of medical device, including in vitro diagnostics. They are as follows:

• Medicines used in combination with a medical device ─ EMA assesses the safety and effectiveness of medicines used in combination with a medical device. This is part of a centralised procedure application for the medicinal product.
• Medical devices with an ancillary medicinal substance ─ the notified body must seek EMA's scientific opinion on the quality, safety, and usefulness of the ancillary medicinal substance in three cases: if the ancillary substance is derived from human blood or plasma; if it has been previously evaluated by the EMA; or if it falls within the mandatory scope of the centralised procedure.
• Companion diagnostics ('in vitro diagnostics') ─ the notified body must seek EMA's scientific opinion on the suitability of the companion diagnostic to the medicinal product if the latter falls within the scope of the centralised procedure.
• Medical devices made of substances that are systemically absorbed ─ the notified body must seek the scientific opinion of a competent authority. The EMA provides scientific opinions on the compliance of the substance with the requirements laid down in Annex I to Directive 2001/83/EC.
• High-risk medical devices ─ EMA supports the medical device expert panels that provide opinions and views to notified bodies on the scientific assessment of certain high-risk medical devices and in vitro diagnostics.