Two-neutrino double-beta decay rates of Ca-46(20)26, Ca-48(20)-28, Ge-
76(32)44 and Se-82(34)48 are calculated with inclusion of neutron-prot
on (np) pairing correlations in describing the ground states of initia
l and final nuclei. Inclusion of np pairing correlations yields strong
er bound nuclei as solutions of the HFB equation. Our results show tha
t even in medium and medium-heavy nuclei, np pairing correlations redu
ce the Gamow-Teller matrix elements compared to the results without np
pairing. Further, the dependence of these matrix elements on the part
icle-particle strength parameter g(pp) is reduced remarkably.