Memories of my first labour – a 20-hour marathon of pain, fear and Entonox-induced delirium – are somewhat hazy, but there is one moment that stands out with complete clarity: when the midwife held up my angry purple baby and said: "It's a girl."
It was a moment of pure elation. Not because I had a preference for a girl – I didn't, and had been happily certain it would be a boy – but because it was the point at which this mysterious being that I had carried for nine months suddenly became a real person.
For increasing numbers of parents, this moment comes at the 20-week scan. Finding out the sex in advance has become the norm, to the extent that the decision to not find out is seen as a bit deviant. After all, if the technology is there, why wouldn't you want to know?
I've heard people compare it to peeking at your presents before Christmas Day and then having nothing to look forward to. For me, the decision was never just about saving up the surprise for the big day. When I weighed up the pros and cons of knowing the sex of my second baby, I could come up with just one reason in favour of finding out – I had boxes of baby girls' clothes in the loft and I would know whether to hang on to them or take them to the charity shop. The reasons for not finding out seemed far more compelling, if at times bordering on the superstitious.
I was single for much of my thirties and therefore never took it for granted that I would have a family. So when I was lucky enough to get pregnant at 39, the idea that I would then suddenly start getting picky about whether I'd be buying pink or blue babygrows seemed preposterous. I was grateful to get a shot at motherhood at all.
A couple of early scans, which flagged up possible problems with the pregnancy (unfounded as it turned out), also served as a wake-up call that there were bigger things to worry about than which colour to paint the nursery. The 20-week scan is, after all, an "anomaly scan", designed to pick up serious structural abnormalities, a fact that can get lost in all the excitement about finding out the baby's sex.
This excitement is perhaps epitomised in the trend for "gender reveal" parties in the States, where the results of the scan are baked into a cake to be shared with family and friends at a special gathering (pink icing for a girl, blue for a boy). Earlier generations would have to wait for their sons and daughters to be born before the colour-coded gender stereotyping could begin; now we can begin the process while the baby is still in utero.
The messageboards of Mumsnet and other parenting websites bear witness to just how much some people invest in dreams of a boy or girl. On threads with titles such as "Gender disappointment, please help", mothers-to-be share their "devastation" at finding out that a longed-for daughter is a son (or vice versa), feelings that they would never admit to in real life. They describe feeling robbed of future shopping trips and pedicures with their fantasy daughters, or "grief" that their husband won't get to watch their son play football.
There is an argument that if you have a strong preference you should find out the sex so that you can "come to terms with it" before the baby is born, but many of the contributors to these online therapy sessions later say that their feelings of disappointment disappeared the moment they held their baby – another argument for not finding out. Surely, when handed their screaming bundle of joy, no one ever yelled at the midwife, "But this isn't what I wanted"?
Although a certain amount of curiosity is natural and we all indulge in daydreams about our future children, the fewer assumptions we make before the baby comes along, the better. Once the sex has been pinned down, the name tends to follow and before the first contraction, little Jessica or Jack's first five years are all planned out.
Of course, there is no right or wrong decision, and we're lucky to have the choice. But the whole experience of pregnancy and childbirth has become so medicalised and closely monitored that I find myself clinging gratefully to this last little pocket of mystery.
In a few short weeks, the wait will be over and, all being well, the tide of pink or blue teddies, balloons and cards from friends and relatives will slowly take over my flat. But for now, the nursery stays white. Joanne O'Connor
I'm embarrassed to admit it, but after my 20-week scan I cried like a baby. Not because the little dear was missing any vital bits, was the wrong size, or any other abnormality had been detected – the tears were down to the sonographer being unable to tell my husband and me our baby's sex. I was over the moon that our first child was developing normally, but we'd always been firmly in the want-to-know camp. Not knowing felt like an anticlimax.
Most people greeted our news with the main argument for waiting: "It'll be such a lovely surprise when the baby arrives!" My family made me see the funny side. On hearing that her grandchild had kept its legs in a tight ball during the scan, my Mum teased: "He/she is obviously as wilful as you!"
My older brother thought it was hilarious and instantly began referring to the baby as Leslie, Vivien and other unisex names. I laughed too, explaining that, when requested to move during the scan, our baby had turned to show us its back and bottom. Asked to perform, our baby basically mooned at us.
As the days passed, I too began to feel I'd been a brat. What a 21st-century indulgence to be able to find out the sex of your unborn child. A worrier by nature, I was acutely aware of the greater upsets we could've experienced at that scan. I'd never taken it for granted that I'd be able to have children and not one day has passed since we found out I was expecting that I haven't felt lucky.
I began to enjoy the ladies at the grocers guessing my baby's gender from the shape of the bump or the opinions of close friends about whether I was a boy or girl creator (the consensus? A boy). For a few brief weeks it felt more traditional, more romantic even, to wait for the big reveal.
But deep down I've never felt at home in the want-to-wait camp. And I feel that expectant people fall into two tribes. Now the technology exists and the possibility is there, it's a rare couple or individual that doesn't feel strongly either way about whether to find out.
I chastised myself that I was being controlling. But really I knew it wasn't that. Furthermore, my husband and I are opposed to dressing our child in gender-specific colours; we don't want to pick out nursery paint; and we definitely didn't want to have a "gender reveal" party (I'm not against such celebrations, but for us even posting the scan photo on Facebook felt self-indulgent, so we didn't).
Those in the want-to-know camp argue that knowing the sex makes name-choosing and bonding easier. But, despite the nausea, odd pains, heartburn and constipation inflicted by the pregnancy, by week 20 we already felt bonded and had boy and girl names we liked.
I can't say for certain what made us secretly go for a private scan five weeks after that inconclusive result. We knew we'd be delighted whatever the sex. And we don't have money to burn. But I do know that I'm a little bit nosey, a big bit impatient and, after a childhood spent with my head buried in books, overwhelmingly a dreamer.
We just wanted to be able to imagine our little family in one, five, 10 years' time and instinctively felt that would be easier knowing the baby's sex.
I realise that, if we're lucky and everything works out OK, it's only about three months before we get to experience that new life every day. But when we were told we were having a girl it felt a step closer. Who knows, maybe we'll regret finding out.
Right now, though, it feels like we'll experience so much excitement and emotion when our little girl arrives that there's no harm in sneaking a slice of it early. Imogen Carter
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