The prevailing belief in many parts of the world is that having children is key to happiness – and that people who don’t have children are unfulfilled in their lives.

But is this really the case? The answer to this question is both simple and complex – and the fulfilment you feel in your life, whether you decide to have children or not, depends on many complex factors.

Let’s look first at the simple answer – which is no, you don’t need to have children to be happy and fulfilled.

Studies in women who are child-free by choice show most feel they have a good sense of identity and individuality. They don’t feel defined by their role within the family, and feel they have more freedom and control over their bodies, lives and future. Child-free women also report greater financial stability – although higher socio-economic status isn’t necessary to be satisfied with the decision to be child-free.

Women and men who are child-free are also less stressed on average, and report greater satisfaction in their marriages.

There is limited research on single men and their experience of being child-free – and even less on the transgender or queer experience of being child-free. But one study of men who were child-free by choice reported that most were satisfied with their decision and happy to have more freedom in their life. Only a small number expressed regrets about their decision – largely because they wouldn’t have a legacy.

However, there is a risk that child-free men may experience a reduction in overall life satisfaction in older age if they lack social support.

 Eudaimonic well-being

Things get a little more complicated when we look at the decision to have children.

While parents can certainly be happy and fulfilled in life, the satisfaction they feel with this decision typically unfolds over time – and can also depend on many factors they can’t control.

Initially, many parents actually experience a temporary decrease in well-being after having a child – a phenomenon known as the “parenthood paradox”. This is because a new baby can come in the way of many basic needs – such as sleep, eating well and seeing friends. This can be a recipe for discontentment.

Straight women also report more unhappiness when they become parents, compared with men. This may be because the burden of care tends to fall disproportionately on women.

But having good family and social support, an active and equally involved co-parent, and living in an area that has supportive work-family policies can all offset the stresses and costs of parenting.

This probably explains why women in Norway don’t report a loss of happiness when they have children, as Norway has many family-friendly policies which make it possible for both parents to raise children and have careers.

While parenting can be tough, that does not mean it cannot still lead to happiness, joy and greater meaning in life. The parenting experience can even lead to a profound form of well-being called eudaimonic well-being. This is the feeling that you have lived a life worth living, which is distinct from short-term happiness.

Both men and women can experience positive eudaimonic well-being when they become parents. But for women, the boost in eudaimonic well-being they experience also depends on how balanced the parenting duties are with their partner.

Facing regret

Another major thing people worry about is whether they will regret not having children.

Reassuringly, research in child-free older adults shows that many report high life satisfaction and resilience against poor mental health.

It seems the biggest key to being happy with your decision to have or not have children depends on whether you felt in control of that decision. When we feel we have chosen our path, we tend to accept our decisions and be happier about them.

What if that choice has been taken away from you – and you wanted a child but were unable to have one? Can you be happy then? Our research shows the answer is a resounding “yes”.

We investigated the impact of childlessness on 161 United Kingdom-based women who wanted to have children but could not for various reasons – such as not being able to find a partner, or infertility. Participants were aged between 25 and 75.

We found that on average, the participants’ well-being was no different from that of the public. While 12 per cent languished (meaning their lives felt aimless), 24 per cent were flourishing psychologically (they reported the highest level of mental health). The remainder experienced moderate levels of well-being.

Interestingly, for some, the struggle to have a child resulted in post-traumatic growth. This refers to positive psychological changes that happen after a traumatic event. Women with the highest levels of well-being said being able to focus on new possibilities in their lives, outside of being a parent, helped them improve their well-being.

Studies of men who have been unable to have children due to infertility show that many experienced sadness as a result – though this sadness did reduce as they grew older. But similar to women who are involuntarily childless, finding ways of reframing their identities and roles in society outside of fatherhood helped many find meaning and satisfaction in their life.

So, does parenthood make us happier? Does childlessness make us miserable? The answer to these questions is not as simple as it seems. The happiness or fulfilment we experience depends on so many factors, many of which are out of our control. While the way you choose to make meaning in your life is indeed a key factor, so too is the social support you have to become a parent, and the political climate you live in.

• Trudy Meehan is a lecturer and Jolanta Burke is a senior lecturer at the Centre for Positive Psychology and Health at RCSI University of Medicine and Health Sciences in Ireland. This article was first published in The Conversation.