Congratulations: you're in labour. But as if waiting (at least) 40 weeks wasn't tough enough, you've now got three stages of labour to get through... and the early stage has three phases of its own. YAY!
To help you pass the time (and figure out roughly what the hell's going on) here's how the whole spectacle breaks down.
The first stage of labour is when your cervix - the neck of your womb - dilates to a rather incredible 10cm (yes, we did in fact say 10) so your baby can squeeze his or her way out.
Understandably, this can take a wee while - typically, at least 12 hours in a first pregnancy (although it can be much longer, you'll be thrilled to know).
AKA pre-labour, this is when your contractions begin, eventually causing your cervix to fully efface and dilate to three to four centimetres in width.
"Eff'ing what?" we hear you cry. Well, imagine rolling down a turtleneck jumper before pulling the neck apart so that you can shove your head through - effacement's that first bit. Except your cervix is the turtleneck (still following?).
On average, for first-time mothers this early phase lasts from six to eight hours, but everyone's different and timings can differ wildly either way.
Typically, contractions during the early phase are mild to moderate (you can talk through them); last about 30 to 40 seconds and are irregular, coming anything from five to 20 minutes apart, and possibly even stopping for a while.
It can be completely exhausting and demoralising to be in what feels like full-blown labour for ages and still only be 1cm dilated. Rest assured that if you turn up at the hospital only to be sent home for being way too early, you won't be the first.
Also called established labour, in medical terms this is when you're fully effaced and about 3-4cm dilated.
Typically, it lasts around six to seven hours if it's your first labour, and finishes when you're about 7cm dilated.
Once active labour begins, contractions typically increase in frequency, length and intensity as the uterus boosts its efforts to open your cervix. If you haven't opted for pain relief, the contractions will soon be too strong for you to talk through them - although, strangely, you may be able to yell.
If you're having a hospital birth, go once you're having regular contractions (every five minutes if this is your first birth, seven if it's not) or can't cope with the pain.
Remember - and we can't keep repeating this enough - everyone's different, so don't get stressed if things go slower than the books say.
That said, if your waters haven't already broken by this point and your labour's progressing slowly, your midwife might suggest she break them as this can help speed things up. You will also have to have this done if your baby needs internal monitoring.
The final, hardest (but, thankfully, usually shortest) chunk of the first stage of labour, this is when you dilate from about 7cm to 10cm.
Contractions will be incredibly intense and you may have very little time to rest between each one. You may feel faint, sick, wobbly, hot and sweaty or cold and chilly. Don't be surprised if you completely zone out during this phase and become unaware of your surroundings.
You may feel an intense urge to push during transition, but don't. Pushing too early, before your cervix is fully dilated, can cause complications.
Transition usually lasts between 15 minutes to a few hours - so bear with. It's more likely to be quick if this isn't your first vaginal delivery.
With a bit of luck, once you're fully dilated, your contractions may stop for a short while before you feel the need to push, giving you the chance to get your breath back.