It's a question you've probably been asked at some point: "do you want to know what childbirth feels like? Place an index finger in each corner of your mouth. OK, now pull your lips over your head." Ouch.
It might be a playground joke but we just can't talk about childbirth without stating how impossibly agonising it is in the same breath. Pineapples, bowling balls and watermelons - and that tribe somewhere who tie a string to the father-to-be's testicles for the woman to pull on with each contraction.
Hilarious, perhaps, but not when you're pregnant. Giving birth is not like a parachute jump; you can't change your mind at the last minute. There's a dawning realisation that what's inside must come out - and, by all reports, the pain levels are going to be medieval.
So you laugh along to all the pub-talk and then you get home, go to bed sober and find that you cannot quite drift off.
I wondered why people don't tell you more about the time in between contractions, when you don't feel in pain at all.
Most pregnant women are very scared of labour. But by putting all the focus on how painful it is, are we failing to give them the full picture? And in doing so, could we actually be making labour worse - in some sense, setting them up to fail?
When I was writing The Positive Birth Book, I wanted to reconsider the widely held idea that giving birth is mostly spent writhing on your back in non-stop agony. Remembering my own three births, I wondered why people don't tell you more about the time in between contractions, when (in a straightforward labour with a well positioned baby), you don't feel in pain at all.
Quite the opposite. In fact, in my own experience - and that of the many mums I've spoken to - in the time between contractions you often feel incredibly strong, excited, or even euphoric. As one woman put it, "It's not a million miles off magic mushrooms, not that I ever tried them, you understand."
How much time do you spend in pain?
I was curious. How much time in labour do we spend in pain, compared to the time between contractions? I did the maths, and the results were surprising. In an average eight-hour labour, a woman can expect to be "in pain" for only around 23 per cent of the time. The other 77 per cent is "pain free".
And even in "the nightmare labour from hell" - 36 hours of contractions coming thick and fast - she can still expect to be without pain for around 60 per cent of the time.
Why does nobody talk to pregnant women about "the 77 per cent"? Imagine you were about to run a marathon, but that everyone you told looked worried and asked you, "I've heard the pain is terrible", or "Did you know people sometimes die running marathons?".
Is the pain heightened by expectation?
When it comes to sport, we all seem to understand just how much negative thoughts can affect your performance physically and mentally. We know how powerful a confident attitude can be. Perhaps it's time to consider that with birth, things are no different.
"A wide range of research shows that our experience can be altered by our expectation," explains Sophie Fletcher, author of Mindful Hypnobirthing. "Sometimes we are unaware of the power we have to change our expectations thereby changing our actual experiences.
"In labour, the mind can be so powerful, for example, a few anesthetists have told me that when giving an epidural, if the mother thinks the drugs have been given, even if they haven't yet, she has a better experience with the next contraction - sometimes completely pain-free."
The language we use about birth can have a similar effect. For example, when you talk to women who are prepared to break with convention and say their labour was not painful, words like "intense" and "powerful" come up again and again. It suggests that it's the way that these women talk and think about these sensations that's different, rather than the sensations themselves.
"I had a pleasurable birth and did not use pain relief," Melissa Carver from London tells me. "I don't find birth painful but I do find it all-consuming and intense at the end. I need to focus inwards and feel supported, then I can become lost in the sensations and enjoy the experience."
Pain versus suffering
The importance of words is also emphasised by childbirth expert Penny Simkin, who stresses the vital distinction between "pain" and "suffering".
"Many women 'suffer' in childbirth, and it's because they're not respected, or kindly treated, they don't have the tools to cope, or they feel unloved, or alone. If a woman crosses the line from 'pain' into 'suffering' in childbirth, we've failed her."
Or, as world-famous midwife Ina May Gaskin put it, "If a woman doesn't look like a goddess in labour, someone isn't treating her right."
The birth environment is crucial
The birth environment, and how a woman's birth partner and care-givers behave around and towards her, during labour, is another overlooked area. Women who experience extreme pain in labour - the sort that causes them to feel that epidural is the only option - often feel afterwards that they have been failed.
"Other women glowed about their natural births and I felt that somehow they were better, tougher women than me - I was simply not up to the job," Karina Price from Cambridgeshire told me.
But dig a little deeper and there's more to the story: "I had wanted a birth centre birth but it was closed at the last minute. I met several different midwives in the hospital. The room was bright and there were constant interruptions. My partner was anxious. I was told I was not dilating fast enough. I was scared but there was no one to reassure me."
The messages about birth seem clear and consistent: it will be agony, you should be scared, don't get your hopes up.
The list of the small ways in which Price was undermined in labour is seemingly endless, and may leave us wondering, did she "fail", or was she "failed"?
Women like Karina are often told the reason they feel low or even depressed about their birth experience is because their expectations were too high in the first place. The guilt and blame is laid firmly at the woman's door and everyone else involved from the medical staff to the wider culture is off the hook.
Getting the message right
The messages about birth - before and after - seem clear and consistent: it will be agony, you should be scared, don't make a plan, and don't get your hopes up, because it's all beyond your control and you will only end up disappointed.
I think it's time to challenge these attitudes. At the moment, we simply do not know what birth would be like for women if they were given more positive messages and went into labour feeling strong, confident and capable. We simply don't know what it would be like if all women were given one-to-one support from a midwife they really trusted, or if we created birth rooms, even in hospitals, that were dimly lit, homely and uninterrupted.
If all of this were in place, and birth still felt like trying to get a pineapple out of your nostril? At that point we could confidently say: take the epidural.