EMA: Comirnaty and Spikevax: heavy menstrual bleeding added as a side effect

The Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) has recommended that heavy menstrual bleeding should be added to the product information as a side effect of unknown frequency of the mRNA COVID-19 vaccines Comirnaty and Spikevax.

Heavy menstrual bleeding (heavy periods) may be defined as bleeding characterised by an increased volume and/or duration which interferes with the person’s physical, social, emotional and material quality of life. Cases of heavy menstrual bleeding have been reported after the first, second and booster doses of Comirnaty and Spikevax.

The PRAC finalised the assessment of this safety signal after reviewing the available data, including cases reported during clinical trials, cases spontaneously reported in Eudravigilance and findings from the medical literature.

After reviewing the data, the Committee concluded that there is at least a reasonable possibility that the occurrence of heavy menstrual bleeding is causally associated with these vaccines and therefore recommended the update of the product information.

The available data reviewed involved mostly cases which appeared to be non-serious and temporary in nature.

Menstrual disorders in general are quite common and they can occur for a wide range of reasons. This includes some underlying medical conditions. Any person who experiences postmenopausal bleeding or is concerned about a change in menstruation should consult their doctor.

There is no evidence to suggest the menstrual disorders experienced by some people have any impact on reproduction and fertility. Available data provides reassurance about the use of mRNA COVID-19 vaccines before and during pregnancy. A review carried out by EMA’s Emergency Task Force showed that mRNA COVID-19 vaccines do not cause pregnancy complications for expectant mothers and their babies, and they are as effective at reducing the risk of hospitalisation and deaths in pregnant people as they are in non-pregnant people.

The Committee reiterates that the totality of data available confirms that the benefits of these vaccines greatly outweigh the risks.

Healthcare professionals and patients are encouraged to continue to report cases of heavy menstrual bleeding to their national authorities.

The PRAC will continue to monitor for cases of this condition and will communicate further if new recommendations are warranted.