According to French scientists with a laser machine, Leonardo da Vinci's Mona Lisa looks like she's in a slightly odd mood because she's pregnant. They discovered that she's wearing a smock, something that women in 16th-century Italy wore before giving birth. There's been a lot of "Ah, well, that makes sense" - mainly from men.
Let's analyse this further. If you've either had a baby or lived with someone having yours, you will have noticed the following pregnancy characteristics.
1. THE VOMITING
This starts early. Almost from the minute after you've lit your fag and said: "That wasn't unpleasant," (my favourite line - and no, my husband doesn't like it much) you start to heave a little.
It's not startling at first, just a small tummy rumble. You go to a restaurant and someone orders haddock, and a tiny bit of sick shoots up the back of your throat. You put it down to prawn madras the night before and tuck into the bread.
Then the waves of nausea grow. It's two weeks in and the bunch of cells in your stomach make you feel like you're on a rollercoaster. You do a test; both the windows have a blue line. After the initial hooray, you've got your head down the loo.
Even if you're not actually following through with a whole bucket of sick, you feel like you want to hurl 24/7. This might in fact be worse because there's no let-up. Instead of old asparagus coming out of your mouth, you just need to spit all the time. No one is supposed to know you're pregnant at this point, so your friends who turn up waving bottles of gin don't understand why you keep guzzling fizzy water, eating breadsticks and dribbling on bits of tissue. The sick thing lasts about 16 weeks and by the end you can't be arsed to get to a bathroom any more. Your home is covered in small mounds of vomit.
2. THE CRYING
This mounts as the months go on but the hormone surge at the beginning really kicks it off.
There's an ad on the telly. A small boy waves goodbye to his dad, a puppy makes friends with an aloe vera plant, and a friend offers another friend a tortilla chip. It's all too much. The weeping begins and it doesn't stop for 40 weeks. Your boyfriend says you don't look chubby and you crumple on the floor in a heap, gently rocking and moaning "thank you". Someone hums the theme tune to Titanic on the bus and you cry out: "Why did Jack have to die?"
3. THE TIREDNESS
"Could you just get me a beer from the fridge, babe?" is replied to with an "ARE YOU MAD?" Brushing your teeth and choosing another pair of elasticated rayon trousers feels like you've walked up Everest. Phoning directory enquiries to get the number for Domino's ("Yes it's, um, for four people and could you just throw in some potato wedges for the morning?") is exhausting. People keep asking if you're doing pregnancy yoga like Gwyneth and you want to cry.
4. THE NEVER-ENDING BAD MOOD
You love life. You're making a tiny little baby and Louis Armstrong's "What a Wonderful World" goes round and round inside your head.
Then people start sharing their opinions. "Seriously though, you're not going to actually call it Fred, are you?" A relative enquires whether you really need that sip of red wine, and people you've never met before retell their birth stories. "I crapped myself during labour"; "Craig hasn't been able to get it up since"; or "You're going to feel such pain, you should consider a general anaesthetic."
The "isn't life good" frame of mind quickly turns into "I HATE EVERYONE". As the months drag on and more strangers come up to have a feel of your bump ("You don't mind, do you?") and every single person you meet wants to know when and where you're having it, if you're going to be going for the non-painkiller option (that'll be a no) and if you're going to let your husband film "the messy end", you start grinding your teeth with anger.
5. THE EXTRAORDINARY WEIGHT GAIN
You start the pregnancy thinking that, Posh Spice-like, you'll eat grilled fish and rocket. By week three you're making risotto for breakfast. The peanut butter talks to you all day, and large hunks of cheddar are eaten as a matter of course. You go from one stone heavier to FOUR stone heavier. You look and feel like Roseanne Barr (pre-tummy tuck) and decide that the only thing left to do for the remainder of the pregnancy is eat. You can't buy knickers in Topshop and you can't get pissed on vodka, so that only leaves family boxes of Celebrations to spend your money on.
6. THE IRRATIONAL FEAR THAT SOMETHING IS GOING TO GO WRONG
This kicks in towards the end, and it's so powerful you can't smirk - let alone smile. Magpies that you haven't even seen are saluted. Umbrellas are banned from the house (even if it's January) and wishbones are pulled with such fervour you almost break your finger. You lie in bed at night praying and praying to a god you've never believed in that your baby is going to be all right.
Boys, Mona Lisa wasn't pregnant. She isn't fat, there's no sick on her chin, she's smiling and she doesn't look like she wants to MURDER someone. She might have just bought a great new dress, she might even have had the shag of her life, but I promise you, she wasn't up the duff.