Regulators worldwide are pulling the breaks on the rollout of AstraZeneca's (AZN  ) coronavirus vaccine on reports of blood clots. Medical professionals around the world are baffled by the decision and are calling on the suspensions to be lifted.

Sweden and Latvia joined Germany, France, Italy, Spain, and Thailand on Tuesday after suspending the deployment of AstraZeneca's vaccine, citing reports that the vaccine is causing blood clots. Despite several European Union members discontinuing their use of the vaccine, the European Union Medicines Agency (EMA) has urged member governments not to stop the deployment.

Medical experts worldwide are joining the EMA in its assertion not to stop vaccine deployment, with AstraZeneca itself also attempting to reassure governments that its vaccine is safe. AstraZeneca pointed to inoculation statistics to back their claim; of the 17 million E.U. citizens that have received the vaccine, there have been less than 40 cases of blood clots reported, as well as 15 reports of deep vein thrombosis and 22 cases of pulmonary embolisms.

"This is much lower than would be expected to occur naturally in a general population of this size and is similar across other licensed COVID-19 vaccines," the company said.

"Around 17 million people in the E.U. and U.K. have now received our vaccine, and the number of cases of blood clots reported in this group is lower than the hundreds of cases that would be expected among the general population. The nature of the pandemic has led to increased attention in individual cases and we are going beyond the standard practices for safety monitoring of licensed medicines in reporting vaccine events, to ensure public safety," said Ann Taylor, chief medical officer at AstraZeneca, in a statement.

Currently, the EMA is working with AstraZeneca to review available data from the ongoing vaccine rollout. The EMA is set to meet on Thursday to discuss the vaccine, though aside from this, little on the investigation (including what investigators are looking for and what data they are using) is actually known.

The AstraZeneca vaccine still has not been evaluated by the Food and Drug Administration (FDA). It's hard to tell what effects the EMA's investigation will have on the FDA's evaluation. The vaccine hasn't yet arrived for the FDA's approval, but some experts theorize that it could be available as soon as April.