It's all the demon's fault chapter 2
Naruto stared at Sasuke both not knowing what to say. Then Tsunade broke the silence.
"There's also some other news."
"What is it bad?"
"Some of it. Well you're about three months along, and you are full of female hormones so some things might happen."
"What things?" Naruto practically demanded the answer.
"Well your body may experience some changes. It could be small or …" She paused and quietly said. "You could pretty much turn into a girl who has male parts."
"I could turn into a girl!" Naruto definitely didn't want to become a girl he was very protective of his manhood.
"I'm not sure I still don't know how a baby is inside of you. You don't have a womb and neither of you have egg cells so it makes no sense at all that you could get pregnant.
Naruto's eyes started to glow with red chakra both Tsunade and Sasuke stared at Naruto worrying that part of the tailed beast was about to appear.
"I can explain everything." The voice coming from Naruto's mouth wasn't his own it had a much more demonic and grizzly tone to it. "It's quite simple really I just gave Sasuke here what he wanted."
"Then what did I want!"
"To make a new generation in your clan. But Naruto couldn't do that because he's a boy. Well I fixed that."
"You're turning him into a girl!"
"No I'm using my chakra creatively. When I heard you complaining so much about how you would love to have kids but sadly you couldn't I decided to be nice and help. I used my chakra to create a sort of artificial womb then all you needed to do was put a bit of your stuff in Naruto. After that all it took was a creative idea and before either of you knew it Naruto was pregnant.
"Still how does it work without an egg cell and why does Naruto have all the female hormones?" Tsunade was trying to figure things out.
" It's easy, you can take an x chromosome from one of the sex cells and combine it with an incoming sperm and add that to some chakra it makes a baby. As for the hormones his body is acting like a pregnant woman's body. Of course he'll have female hormones."
"So it's a partial clone?"
"Not really the kids will be like if Naruto was a girl and he had kids naturally. Well I'm tired of explaining now."
"What just happened?"
"The tailed beast inside of you just explained why you're pregnant."
"Well how am I?"
"It's kind of a long story I'll explain it tomorrow. C'mon let's get home."
"Not until I give Naruto all the prenatal vitamins he'll need and instruct him on proper dieting when you're pregnant. You can't just keep on eating nothing but ramen."
Naruto then knew it was going to be a long night.
So how very scientific and realistic was my explanation? I know chakra doesn't exist in the real world but all the other stuff makes a lot of sense. Pease review and if you want to pm me on your ideas on how mpreg works!