Parents with two kids are the happiest: Study

For several years, my husband and I were adamant that our son Isaac would be an only child. Despite having had an easy pregnancy and complication-free C-section, parenthood was like a hard punch to the gut.

There were the all-night feedings, failed attempts at breastfeeding (which led me to exclusively pumping), crippling postpartum anxiety, the stress of finding a daycare and returning to work. Then, before we knew it, we were in the midst of the "terrible twos" (and who dreams of adding a baby to the family dynamic in the middle of the "terrible twos"?!) Having a second baby was something we took very seriously. In the end, we ultimately conceived Gillian because we felt our family wasn't complete.

The early days with our second child were just as difficult, if not more so. The second time around I struggled with postpartum depression—which was far worse than the anxiety I experienced with Isaac. When asked by friends and family if we're considering having a third baby, my blunt and immediate response often takes people of guard. I know that a third child, for me, would be devastating to my mental health.

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It makes me wonder if there really could be something then to a new study out of the London School of Economic and Western University, which suggests that the number of children a family has is directly related to how happy they feel.

According to the study, which followed couples for 18 years after the birth of their children, parents’ happiness increases in the year before and after the birth of a first child, before it quickly decreases and returns to their "pre-child" level of happiness. Researchers found that the birth of a first and second child briefly increases happiness, but a third does not. The findings were published in the journal Demography and is based on data compiled from Britain and Germany.

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“Our results show a temporary and transitory gain in parents’ happiness around the birth of first and second children. The fact that parental happiness increases before these children are born suggests that we are capturing broader issues relating to childbearing such as couples forming partnerships and making plans for the future," says Mikko Myrskylä, professor of demography at LSE and Director of Germany's Max Planck Institute for Demographic Research.

Myrskylä lists several factors that could contribute to the dip in happiness parents feel with the arrival of a third child: The experience of parenthood is less novel and exciting, a larger family puts extra pressure on the parents’ resources, the likelihood of a pregnancy being unplanned may increase with the number of children a woman already has. "This brings its own stresses," Myrskylä notes.

Of course, that isn't to say that the third (or fourth, fifth or sixth) child is no more loved than the first. I have several friends with large families and often all I see is an abundance of happiness that makes me a little jealous. But, at the end of the day, I know that, for our family, two is the perfect number.

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Follow along as Jennifer Pinarski shares her experiences about giving up her big city job and lifestyle to live in rural Ontario with her husband, while staying home to raise their two young children. Read more Run-at-home mom posts or follow her @JenPinarski.