The dilemma I am married and in my late 30s. My husband and I are happy in all aspects of our lives. We have both (individually and together) chosen not to have children. I have never felt "maternal" and while I love children I have never been tempted to have my own. I believe that if I had been a decade younger when I got married, or if my husband had been very eager to be a father, I might have acted differently, but I have felt this way pretty consistently my whole life. I don't see this as a problem, but people around us do. Family and friends tell us of the regret that will inevitably set in a decade from now, especially when I realise that I cannot have children biologically. Others tell us that our relationship will become weaker with no children to hold it together. I understand all of this intellectually, but my gut tells me that my decision is correct for me and my husband. Am I missing something? Is it so unnatural for a woman not to want her own child?

Mariella replies Unusual but not unnatural. Centuries of propaganda tell us we're created in order to procreate, but the great thing about being human is that you get to make your own choices. To have or not to have children is one of the burning questions. It's a decision further complicated by the fact that it's one of the few areas of our physical lives where time actually does run out. You can run a marathon at 60, learn to scuba dive as a septuagenarian, but once your cache of eggs runs out your procreating days are over (though, happily, that situation is improving).

Your friends are right to make you focus, but not to suggest there is a right and wrong way for you to go. We're too brilliant as creations for our lives to be purely predicated on sustaining the species. People achieve posterity and contribute to the future of mankind in myriad ways, from writing symphonies to discovering penicillin, curing cancer, writing a literary opus or saving their next-door neighbour's cat.

The popular theory that a woman's only purpose on the planet is to make babies dates back to the dark, pre-emancipated ages when giving us ideas above our station could have led to the unsavoury prospect of equal status. Along with the miracle of carrying children, we can also push our bodies to perform Olympic-style feats, and rise to all sorts of other physical fabulousness – so there's no reason that childbirth should be any less of a right to choose than other challenges.

Living your life childfree has plenty to recommend it, including enhanced personal freedom and less financial stress – and neither option is to be sniffed at. Funnily enough, parenting, though one of the hardest choices you'll have to make, is one of the few life-changing events that doesn't bear up to much scrutiny. There's no obvious appeal to a lifetime of attachment to offspring who feel none of the same responsibility to you and spend their teens working out how to dump you altogether.

No one goes into parenting for an easy life and you won't see the upside until you've already made the choice. Procreation is the embodiment of Catch 22. Having felt like you for much of my 20s and 30s and, later, the awful desperation of one who may have left it too late, my best advice is to seriously think about the choice you are making. When I confronted my own reticence I realised it wasn't that I had no desire to be a mother but that my own experiences of childhood had made me reluctant to foist something similar on another innocent.

Once I'd considered the irrationality of my fear and decided I had the wherewithal to do things differently I began to actively want to be a parent. Luckily for me I wasn't too late. You may not come to a similar conclusion, but before you reach the point of no return ensure as best you can that you are clear on your reasoning and sanguine about its drawbacks as well as its advantages. Your husband has the luxury of changing his mind; you don't.

The important and lasting choices we make, with potential ramifications over decades, should be selfish ones barely influenced by others, and made by keeping a firm eye on circumstances that may change. Couples do split up more easily without children (if equally painfully); life does become an existential argument that's hard to lose if you're looking at how your babies and kids can enlarge and improve our lives. Doing what's right for you is often a guessing game and none of us is infallible in our choices. Nobody can tell you whether you should be a parent, but good friends will hopefully continue to remind you that it's a choice that has to be made with your eyes wide open.

If you have a dilemma, send a brief email to mariella.frostrup@observer.co.uk. Follow Mariella on Twitter @mariellaf1