A link between changes in the menstrual cycle and COVID-19 vaccination is plausible, and must be investigated, according to an editorial published in the peer-reviewed British Medical Journal today.
In the editorial, Victoria Male, a reproductive specialist at Imperial College London, UK noted that periods or unexpected vaginal bleeding are not listed as common side effects of COVID-19 vaccination.
Over 30,000 such reports had been made to the UK Medicines and Healthcare Products Regulatory Agency (MHRA) surveillance scheme for adverse drug reactions by September 2, she said.
The expert, however, noted most people find that their period returns to normal the following cycle and, importantly, there is no evidence that COVID-19 vaccination adversely affects fertility.
"One important lesson is that the effects of medical interventions on menstruation should not be an afterthought in future research," Ms Male said.
MHRA states that its surveillance data does not support a link between changes to menstrual periods and COVID-19 vaccines, since the number of reports is low in relation to both the number of people vaccinated and the prevalence of menstrual disorders generally.
However, Ms Male said the way in which data is collected makes firm conclusions difficult.
She argues in the editorial that approaches better equipped to compare rates of menstrual changes in vaccinated versus unvaccinated populations are needed.
Reports of menstrual changes after COVID-19 vaccination have been made for both mRNA and adenovirus-vectored vaccines, she said.
This suggest that, if there is a connection, it is likely to be a result of the immune response to vaccination, rather than to a specific vaccine component, Ms Male said.
The editorial also noted that the menstrual cycle may be affected by the body's immune response to the virus itself, with one study showing menstrual disruption in around a quarter of women infected withS-CoV-2.
If a link between vaccination and menstrual changes is confirmed, this will allow individuals seeking vaccination to plan in advance for potentially altered cycles, she explained.
She suggests that doctors should encourage their patients to report any changes to periods or unexpected vaginal bleeding after vaccination to the MHRA's scheme.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
Skincare Tips: What Is Skin Barrier? How Can You Protect It? Covid Vaccines Didn't Increase Sudden Death Risk In Young Adults: Study Covid Vaccine Booster Gives Effective Antibody Protection Against Omicron: Study Parents Gave Names Of Interns, Doctors To CBI In Kolkata Horror: Sources Who Is Jasveen Sangha, "Ketamine Queen" Charged With Matthew Perry's Death How Extreme Weather Is Leading To Rise In Child Marriages In Pakistan Blinken Heading To Israel To Press Gaza Truce 'INDIA' Is with You Against "Injustice": Rahul Gandhi To Arvind Kejriwal "Strong Indications" Bangladesh Security Forces Used "Unnecessary" Force: UN Track Latest News Live on NDTV.com and get news updates from India and around the world.