I believe that they have humans life span
Betazoids seem to be very humanoid, the differences being in having a paracortex for telepathy and what looks like aniridia... ProfessorTrek 05:19, July 17, 2011 (UTC)
Betazoids can get pregnant much later in life than humans. Since organisms that raise their young to adulthood must live long enough to do so, to say Betazoids have a longer lifespan than humans would be an educated speculation, but their lifespan has never been mentioned in canon.
When you say "can", you must mean "can naturally", because with the right hormones, it's been proven that Human females can have successful pregnancies into their late fifties.
Is this canon?