Iain Murray summarizes three recent studies on marriages within the impoverished. The studies were done by the Heritage Foundation, the Urban Institute, and National Institutes of Mental Health/University of Canterbury.
For unemployed single-mother-headed families, for example, marriage pushes 65 percent of the children above the poverty line (from all the kids being below it prior to marriage); nearly a third of the children in this family category rises 50 percent above the poverty line. Mothers employed part-time and full-time who wed see even bigger gains for their kids....70 percent of marriages entered into because of a child's birth or impending birth still endured 12 years later--not much worse than the figure for more traditional marriages where the ceremony occurred before pregnancy (85 percent). "Shotgun" marriages are less fragile than many believe.
Murray's summary is very short and worth the read. More and more research is supporting the wisdom of our grandparents - marriage is the surest way out of poverty.
Note: I suspect the percentages given for successful marriages may sound high to those of you unfamiliar with these studies. However, the typical media claim that "50% of marriages will end in divorce" is simply wrong. It is difficult to give an exact figure, but estimates range anywhere from 12% to 35% of all people will be divorced at one point in their life. In addition, the surveys mentioned by Murray seem to be for first-time marriages. The odds for first-time marriages are quite favorable in most situations. Marriages where at least one partner has already been divorced are less likely to succeed than marriages consisting of two first-time spouses.