If you’re unhappy in your marriage don’t blame your spouse — blame your kids.

A new survey has found that couples without kids have more pleasant relationships that those who have procreated.

The authors of the report by the UK’s Open University say they looked at numerous factors that make happy relationships.

They didn’t explain why kids make couples less satisfied. But they said the survey of 5,000 came to the conclusion that “childless married and unmarried participants are happier with their relationship and their partner than parents.”

They added, “Unmarried parents are slightly happier than married parents.”

They also suggested ways to make things better.

“Actions really do speak louder than words, and many people consider a loving gesture to be as valuable as hearing ‘I love you,’ ” said the report’s co-author, Dr. Jacqui Gabb.

“Grand romantic gestures, although appreciated, don’t nurture a relationship as much as bringing your partner a cup of tea in bed, or watching TV together,” she said.

Despite the findings that married couples are the most unhappy, all is not bad for parents.

The study found that “mothers are the happiest in their life than any other group.”