"Basketball Wives" star Evelyn Lozada has been keeping a big secret -- she's 6-months pregnant -- and TMZ has learned Chad Johnson is NOT the baby daddy.
Sources close to Lozada tell us ... she's been seeing a guy for almost a year now and the relationship has gotten serious.
We're told ... the pregnancy was planned -- it's not a case of the whoops! And until now only a small number of relatives were privy to the news.
Lozada famously divorced Chad Johnson in Sept. 2012 ... after an explosive domestic dispute ended their 2-month-old marriage.
BTW ... Evelyn already has a 20-year-old daughter, Shaniece ....born when Lozada was 17.