I’ve got some news for you. The zombie apocalypse is happening all around you. But until you’re infected, you don’t even know.

Watch out for the signs. Irritability. Mismatched socks, or even shoes. Unbrushed hair. Vomit stained clothing. An inability to concentrate. An urge to seek out caffeine and high calorie food substances. And a vague, manic look in bloodshot eyes.

Zombies are traditionally infected by being bitten, but in this epidemic it’s self-inflicted, caused by the act of procreation.

It was only when I returned to work after having my first son that I realised the extent of the epidemic. Pandemic, even.

Colleagues I had previously thought were cranky, a bit odd, or just plain evil were actually just sleep-deprived zombies. Now that I had joined their ranks – getting an average of three sessions of 90 minutes sleep per night before producing a live three hour phone in radio show – I knew the signs. And I had become one of them.

Lunchtimes spent hunched over the kettle, frantically sharing notes about sleep strategies. Casual encounters on the staircase, bitterly comparing duration, cause and effects of baby wakefulness. A secret society, almost, of zombies.

Parents the length and breadth of the country will have laughed bitterly reading news reports about a new study on parental sleep patterns published in the journal Sleep recently.

The study, conducted in Germany over a number of years, set out to establish how sleep patterns change when people become parents. If you have young children, you’re already shouting “sleep, what sleep!” while reading this, and if you don’t, you’re shaking your head dismissively at this snowflake generation of young parents.

The survey results were pretty surprising, however, finding that new mothers lost an average of 40 minutes sleep every night. Fathers lost 13 minutes per night.

Maybe things are different in Germany, but pretty much everybody I spoke to about this would be absolutely thrilled to lose just 40 minutes of sleep with a new baby. That’s kind of the ideal scenario.

As for the fathers, perhaps every German woman breastfeeds, because 13 minutes isn’t even enough time to give a bottle.

Reactions on social media varied from shock to homicidal rage, as we all wondered what kind of magical mathematics makes 40 minutes the average sleep loss when so many of us are losing hours and hours. A (hugely scientific) poll I conducted on instagram found that 95% of my 700 respondents lost more than 40 minutes sleep when they had kids. Of the other 5%, one person messaged me to say she had hit the wrong answer because she was so tired.

Perhaps those people whose unicorn babies sleep through the night are in fact everywhere, but only the most foolhardy among them will disregard the mania in your sunken eyes to say so.

I have spent much of the past two and a half years comparing notes in Facebook groups. I bought a baby sleep book and ten pages in, was bawling at what terrible parents we were, doing everything wrong. My husband threw it in the bin. We kept soldiering on.

My older son woke between four and five times every night until he was 17 months old. Nothing on earth could have prepared me for the relentlessness of it. Absolutely nothing. When you watch the dawn breaking for the twenty-fifth day in a row and realise your entire day is going to be spent the same way you just spent the night – huddled over a cranky baby, back sore, boobs sore, everything a bit damp – it’s overwhelming.

Going back to work is almost a relief – at least the daytimes offer a change of scene – but if you have a bad sleeper, you know that the 16 hours you’re not at work are the challenging part.

The first time my son slept the night, we both woke at 90 minute intervals to check he was still breathing. My second has had a much better run – but at five months old he still wakes on average twice a night.

Modern society has very unrealistic expectations about children’s sleep. If I had a euro for every time someone has asked me if they are sleeping the night yet, I’d have enough to buy myself a place on a fancy ‘sleep retreat’ (they exist – google them). Experts say five hours is a full night’s sleep for a small baby.

Research shows that most adults don’t sleep the night fully either – we enter a state of semi-wakefulness a few times during the night, but we have trained ourselves to fall back to sleep. Babies don’t have that knowhow. They need us to soothe them, cuddle them, and be a physical presence that indicates security. Those cuddles are a crucial part of their development, and the duration of that need varies massively between children.

Unfortunately, the survey also showed that parental sleep patterns never return to their pre-baby levels. Nappies and feeding are replaced by teething, sicknesses, insomnia-inducing worries about creche fees, and, eventually, their whereabouts at night.

So if you’re in the trenches with number one, trying to figure out if there’s a way to give them back, dare I say, you get used to it. Almost three years in, we’ve adapted somewhat. Our expectations are lower. A lie-in until 7am is a bonus, and getting more than four hours sleep in a row is a golden ticket. And – to those German men in the study who are clearly not doing their fair share – it makes a huge difference when dad does his fair share. And, as so many older people have reminded me, you will look back on this time when they’re grown up, and wonder at how fast it passed. Apparently…

The Herald, 28.02.19