I wouldn't say I regret any of my 4, perhaps who their father is LOL, but not them. I'm having #5 soon & I cant wait, yeh sure it's tough sometimes but more often than not it's great! When #5 comes we will be considering #6, but I'm already 34 so maybe not such a good idea, Zac's pg & this one has been really tough on me, but it is still worth all the complaining. I had my first 3 close together, about 2 years & then a big gap of 9 years between 3 & 4 which, truly was awesome! I do have great helpers in my older ones, ( ah if only they'd change a stinky bum) so i am really lucky there.
I reckon just let nature take it's course IYKWIM