Brian Doss, a psychology professor, said an eight-year study of 218 relationships found the arrival of a couple's first child was often followed by increased problems, a decrease in their confidence the marriage would last and declines in their overall satisfaction with the marriage, the university said in a news release.
The researchers found couples who were married longer and had a higher income appeared to have fewer problems after the birth of their first child.
The findings are published in the Journal of Personality and Social Psychology.
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