Sorta.... Thing is, how much income is enough?
If someone is unemployed or living with parents or generally "on subsidy" then IMO they should avoid pregnancy (and certainly sex if not married).
As a GENERAL rule, I think people should be READY (emotionally, economically, etc.) for marriage,for sex and for kids.
But "ready" is a pretty subjective thing*
* On a related note, I've always thought the whole "family education" thing of "don't have sex until you are ready" ploy is ABSURD and beyond silly.... I've never met a 14 year old boy who didn't think he was ready!