I think that 8 out of 10 oops babies arn't really oops they are just broody women that want a baby and they want to make it look like an accident! I know 3 people that have had oops babies the story goes something like this...
My friends sister 23 years old, half way through a nursing degree, getting bored of it! Her cousin was round with her baby and i overheard her say "i would have one today if i wasn't doing my degree" 2 weeks later she was pregnant!
My best mate got pregnant the other year with her second, she said it was an accident and was even upset but i asked her what bc she was using and she said nothing! i said well it wasn't really an accident then was it! and she said "i didn't think i would get pregnant again"
No disrespect shes my best mate but how dumb can you get? she has already got one child what made her think she wouldn't again?
I also know someone that was on the pill and she was forgetting to take them all the time but she even admitted she didn't care if she got pregnant and sure enough she did! she told her boyfriend it was an accident but really she planned it!
So im sorry if there are any people that have genuinly had opps babies in the past but i think that most of the time its down to planned oops to trick the husbands lol