Since my son was born at the end of last year I've had many, many opportunities to realise how lucky I've been. Not only is he an utter joy to be around but he's also a happy, healthy, bouncing little boy who eats pretty much everything and sleeps easily. Even the arrival of teeth has, so far, been relatively untraumatic – nothing worse than a couple of days discomfort and some teething gel.

I know I've been lucky because I know how easily things could have been different. Friends with kids exchange horror stories about the colicky babies who can't sleep for longer than two hours at a time, for months on end. The ones who will scream for hours every night after being put to bed. The babies who can't or won't eat without elaborate preparation or persuasion. Every baby is different, for reasons that have nothing to do with parental aptitude.

And even without those complications, a healthy and happy baby is still hard work. Sleep deprivation means the first three months or more after birth are spent in a zombie's fog of stumbling misery for both parents. Minor events turn into major crises – just leaving the house, with or without the baby, takes on the status of an heroic expedition. Finding time to have a shower or even eat becomes surprisingly difficult. I can't begin to imagine the additional stress of going through all of that while at the same time recovering from childbirth – and possibly a major operation, if a c-section was involved – and in many cases having to learn to deal with breastfeeding as well as everything else.

We know, of course, that many women do feel overwhelmed by the experience, and that some are unlucky enough to suffer from severe forms of postnatal (or postpartum) depression, around one in 10 mothers in the UK and the US. What is more rarely discussed is that fathers can suffer from many of the same symptoms and a significant percentage – 4%, in one study – go on to develop depression. That 4% figure comes from a UK population-based study by Dr Paul Ramchandani and colleagues, published in the Lancet in 2005, into paternal depression and childhood development. It concluded: "Our findings indicate that paternal depression has a specific and persisting detrimental effect on their children's early behavioural and emotional development."

Exactly what the "detrimental effect" was is made clearer in a subsequent review by Ramchandani, published in the Lancet in August this year:

Most psychiatric disorders that affect fathers are associated with an increased risk of behavioural and emotional difficulties in their children, similar in magnitude to that due to maternal psychiatric disorders. Some findings indicate that boys are at greater risk than girls, and that paternal disorders, compared with maternal disorders, might be associated with an increased risk of behavioural rather than emotional problems.

It shouldn't be surprising that men can suffer from such disorders too. Looking at the NHS's guidelines for maternal postnatal depression, the list of possible causes includes worry and anxiety about the responsibility of having a new baby; relationship worries; money problems; having no close family or friends around you; and mental health problems in the past. The symptoms include: low mood for prolonged periods of time (a week or more); feeling irritable for a lot of the time; tearfulness; panic attacks or feeling trapped in your life; difficulty concentrating; lack of motivation; lack of interest in yourself and your new baby; feeling lonely; feeling guilty, rejected, or inadequate; feeling overwhelmed; feeling unable to cope; and difficulty sleeping. It's a rare new parent of either sex who wouldn't identify with several of those characteristics. As with depression in general, though, it's when perfectly normal responses to stress and circumstances are amplified and aggravated that illness can develop.

It's important to note a couple of things here. One is that the existence of paternal depression does nothing to diminish the fact of maternal postnatal depression, if anything quite the reverse, as I'll explain. The other is that more research needs to be done, although that's hardly a stunning conclusion to arrive at. But there is a point: what is it specific to men or fatherhood that can provoke paternal depression? What research there is suggests it is strongly linked with maternal postnatal depression. A recent article in the New York Times noted:

By far the strongest predictor of paternal postpartum depression is having a depressed partner. In one study, fathers whose partners were also depressed were at nearly two and a half times the normal risk for depression. That was a critical finding, for clinicians tend to assume that men can easily step up to the plate and help fill in for a depressed mother. In fact, they too may be stressed and vulnerable to depression.

So, the easiest way to prevent paternal depression would be to prevent maternal depression to begin with, while recognising that paternal depression is also a possibility. Yet, in the prenatal and perinatal books and classes I absorbed last year, at some point there would be a brief and tactful section entitled "For the partner", which would usually begin along the lines of: "During pregnancy and after giving birth, many women experience something known as 'baby blues'. This is not unusual. But in a few rare cases ..." followed by a sketch of postnatal depression. Given the prevalence and seriousness of maternal depression, that's inadequate. Looking back, all those classes about childbirth might have been more usefully spent concentrating more on what happens after you both leave the hospital.

Since my son was born, I can't think of a single aspect of my life that hasn't been affected by his arrival. That's something that can be difficult to come to terms with. Perhaps in my parents and grandparents' generations, less was expected of fathers in the earliest months of a baby's life – and we all know who got the raw end of that deal. Although we can debate the extent things may have changed, fatherhood is now a different experience. It's right that fathers are involved as much as possible in the lives of their children, from the beginning: another reason why I've been lucky is that the Guardian is an enlightened employer with a sensible attitude to paternity leave.

Other parents, especially here in the US, aren't so lucky. Penelope Leach's latest book, Child Care Today, published this year, argues that governments need to recognise the changed role of fathers, and suggests specific ideas for easing the financial pressure to allow families more time together. That's useful advice – although in the lonely hours of 3am, with a crying baby needing to be rocked back to sleep, there's no better advice for any parents than Leach's own introduction: "Whatever you are doing, however you are coping, if you listen to your child and to your own feelings, there will be something you can actually do to put things right or make the best of those that are wrong."