The 85-year-old justice went to George Washington University Hospital in Washington after experiencing discomfort overnight.
Ginsburg was admitted to the hospital for treatment and observation after tests showed she broke three ribs.
More details to follow ... She has reportedly broken three of her ribs.
It means Ms Ginsburg will not be present for Thursday's investiture of new Supreme Court judge Brett Kavanaugh, whose appointment led to protests following allegations of sexual misconduct.
Since taking office, President Donald Trump has appointed two conservative justices to the court, shifting it to the right.
In the 2018 midterm elections, Republicans won seats in the U.S. Senate, making future Supreme Court confirmation battles easier.
Ginsburg leads the court's liberal wing.
"I will retire when it's time", Ginsburg told NPR's Nina Totenberg in 2016.
Ginsburg's heath has been the subject of public concern as the court's oldest justice is one of four liberals on the bench.
Asked previous year if she was contemplating retirement, she said, "As long as I can do the job full steam, I will do it".
For what it's worth, Ginsburgh apparently has no plans of stepping down, and has even hired clerks for the term that extends into 2020.