WNBA's Glory Johnson -- I'M HAVING TWINS ... With or Without Brittney

WNBA star Glory Johnson just announced ... she's carrying TWINS ... and says it's exactly what she and her estranged wife Brittney Griner planned all along.

Johnson says she's 9 weeks preggo with the two kids -- and says, "Its not a surprise for me because this is what we planned for with the IVF Cycle."

As we previously reported, Griner distanced herself from the pregnancy in court docs -- saying she has no biological connection to the kids and didn't know any of the key details about the pregnancy.

But Glory is remaining positive ... saying, "Hearing their hearts beat for time was the most ASTONISHING thing I have ever heard in my ENTIRE LIFE."

Her announcement even came with a basketball pun -- "For 15yrs Double-Doubles came with hardwork and dedication...now I've been blessed by God to have "double doubles" for the rest of my life!"