For me its:
Periods and all the talk about who has 'started', trying to hide the rustling of my big fat sanitary towels from the other girls (who would all have been having periods anyway) in the loos.
Boobs growing and that transition from 'crop top', to 'junior bra' to 'proper bra'.
Being smaller and weaker than lots of people and becoming aware of the implications of that as I got older.
Walking along the street in my tracksuit bottoms and Gap hoodie and being catcalled by blokes hanging out of a white van. Wondering if I am supposed to be flattered by this because I just feel plain old uncomfortable.
Sexual experiences which just felt 'wrong', because I didn't say no but I wasn't really up for it either.
One particular experience where I know I said no, but they carried on anyway and afterwards I didn't really think much of it because I was drunk and I went back with him, but here I am still thinking about it 15 years later.
Marrying a great bloke who loves and respects me and is always willing to equally share the load.
Remembering to have to take a little pill each day to make sure that when said husband put his penis in my vagina and ejaculated sperm cells, the sperm didn't meet with my ova and conceive another human.
Deciding to stop taking that pill so that we could see if putting his penis in my vagina would result in the human that we decided that we would like to make.
Carrying baby in my uterus for 9 months, being sick every single day for 3 months, waving goodbye to my jeans that I have never seen since, watching my stomach expand to comic proportions, before being in labour for 3 days and finally that baby being hauled out of my vagina with barbecue tongs.
Feeling the mad rush of happiness the day after my baby was born.
Experiencing the utter shock that was breastfeeding in all its milk squirting, leaking, excruciatingly painful, huge titted glory.
Deciding that it wasn't for me and breaking open the Aptamil at 4 weeks and starting to enjoy my baby.
Doing the whole thing again 2 years later.
Going for smear tests and hoping its all OK.
Deciding that I didn't want to have to remember to take a pill each day, so going for a mirena coil because it sounded fab, but actually finding out it just makes a spotty, bitchy, bleeding, sore titted mess.
Trying to decide what to do next because we definitely don't want anymore kids, but unless DH gets the snip it's on me to sort it.
Getting older and it becoming clear that women really do get a shitty deal a lot of the time.
Christ that was long, sorry, but it felt quite cathartic! I'm sure there is more I could think of.
I genuinely fail to understand how anyone who wasn't born with a female body knows they are 'actually a woman'.