Twins twins twins

Twins each deliver set of twins
Two twin sisters are seeing double or make that quadruple after delivering two sets of twin boys Tuesday.
Twenty-one-year-olds Ashlee Spinks of Indianapolis and Andrea Springer of Conyers, Ga., delivered their boys by scheduled Caesarean sections Tuesday about an hour apart at Northside Hospital.
The women were six months pregnant when they found out they were both going to have twin boys due on the same date Jan. 1, 2005.

[Note] This is really weird. What are the chances of this? At the end of the article the doctor said that the chances were "one in a million". I think it's probably a little more uncommon than that....