A Pennsylvania woman was one of six people in the U.S. who were hospitalized with blood clot issues after receiving the Johnson & Johnson coronavirus vaccine, the New Jersey Department of Health confirmed with NBC10. 

The woman was hospitalized in New Jersey and is the only one of the six people to have been released from the hospital so far. All of the women are under the age of 50. 

The news comes the same day government health advisers declared that they need more evidence to decide if a handful of unusual blood clots were linked to the J&J vaccination. 

The reports are exceedingly rare — six cases out of more than 7 million U.S. inoculations with the one-dose vaccine. But the government recommended a pause in J&J vaccinations this week, not long after European regulators declared that such clots are a rare but possible risk with the AstraZeneca vaccine, a shot made in a similar way but not yet approved for use in the U.S.

Health officials recommended the J&J timeout in part to make sure doctors know how to recognize and treat the unusual condition. The CDC said Wednesday that four of the six women with the unusual clots were treated with a blood thinner named heparin — a treatment the government is warning doctors to avoid.

The setback for J&J comes as the worldwide death toll from COVID-19 approaches 3 million, including more than 560,000 who perished in the U.S., which continues to report tens of thousands of new infections every day and an average of almost 1,000 deaths.

So far, the J&J vaccine has been a minor player in U.S. vaccinations. More than 122 million Americans have received at least one vaccine dose, and nearly 23% are fully vaccinated. Moderna and Pfizer are on track to have delivered 300 million doses each by mid- to late July. Pennsylvania, New Jersey and Delaware are all following federal guidance by putting Johnson & Johnson vaccines on hold.