Summary:
Upon the brink of delivering good news, Naruto catches his lover having an affair. Leaving Konoha with a secret, Naruto stumbles into the arms of someone he thought untouchable. ItaNaru.

Pairings:
Itachi x Naruto, Sasuke x Naruto (onesided on Sasuke's part), Sasuke x Sakura (onesided on Sakura's part)

Warnings:
Mpreg (but what I consider to be plausible, that means no Kyuubi inteference, no Naruto-growing-girly-bits thanks to the Kyuubi, no terrible mood swings or complete change in character), battle violence, character death (major and minor, but will end happily), infidelity, swearing, mentions of terminal illness. Sasuke comes with his own warning in all honesty, but thoughts of causing miscarriage. Spoilers for current manga. No character bashing.

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What You Didn't Know

Chapter One

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Naruto screwed his eyes up tightly, wiping his mouth as he breathed deeply through his nose. The porcelain toilet bowl was an unwelcome addition to his morning, but it could have been worse. He hadn't eaten breakfast yet, but just the hint of toast had sent him crawling out of bed into the bathroom, retching into the toilet.

Flushing the toilet, Naruto stood and faced the bathroom mirror. His face was pale, flushed from his efforts at throwing up, and clammy. Overall he looked ill, hardly the face of someone who was a successful shinobi, and Sasuke had finally booked an apointment for him at the doctors.

Sasuke. Naruto had been with Sasuke for almost three years now, since when they were sixteen. Reluctantly, Naruto had allowed Sasuke to seduce him, secretly thrilled at the persuit, and it had been easy to accept Sasuke's love. They had both craved each other, even back when they were genin and on Kakashi's Team Seven. It just so happened that, later down the line, they turned emotions into actions, moving in together a few months into their newfound status of a couple.

Sasuke had already left, saying he had a mission to write up with his team. It wasn't as though that was uncommon, being a high jōnin was very demanding at times. Naruto understood that, after all he had been in Sasuke's position a few years ago, but it wouldn't hurt for Sasuke to leave a note from time to time.

Padding through the living area and into the kitchen, Naruto took an apple from the fruit basket, teeth tearing into the crunchy flesh. A little juice escaped his mouth and ran down the corner of his lips, being wiped away a second later by his thumb.

It had been about two weeks since the symptoms had arrived and Naruto had taken a standard absence leave from his ANBU team. He never took his holiday anyway and they had said the reason Naruto was ill was probably due to the fact that he was a work-a-holic. That much was true, but even with the rest and recovery, Naruto had failed on the latter point.

It had gotten to the point where Sasuke didn't want to sleep in the same bed anymore, pushing Naruto away with a frown.

"I don't want to catch it," he'd mumbled in the middle of the night, after coming back from a jōnin meeting. Naruto had heard his team mates dropping him off, head tucked under the pillow as the rowdy calls of Sasuke's team echoed around their home, despite their drunken shushes.

Sasuke, however, wasn't drunk. He didn't even have that excuse to fall back on in the morning and had, instead, woken Naruto up from the sofa with yet again a frown.

"I'm off for a few days, mission," it was blunt, almost brutal, and reminded Naruto of their recent sex life.

Which was a sad thing, really.

Though Sasuke meant well, and with Naruto off of his shinobi duty, they did need someone to bring in money. Not that they needed it now, per se, but it was always nice to be able to actually buy friends good gifts for their birthdays.

The appointment card was on the kitchen table, propped up against the glass fruit bowl. Naruto took it in his hands gently, running a hand over Sasuke's writing, and noting that he had half an hour before the appointment. It would be a simple check up, possibly be prescribe some kind of pills to get rid of whatever it was, and then he'd be able to go back to cuddles in the morning with Sasuke.

Alone, Naruto hummed to himself, ignoring the queasy feeling in his stomach. It was normal now, and he could adjust around it. In the mornings, though not every morning, it was the worst and he ended up hovering above the toilet pan, convinced he'd throw up his spleen or something.

It hadn't been documented, but who knows. Naruto knew he liked things that were out of the ordinary, why should his vomiting habits be any different?

Ten minutes later, Naruto left the house with a smile, in casual clothes. His appointment was with Tsunade, upon request as Naruto didn't really trust anyone else with his medical records. Even though people had accepted him, loved him even, mentioning the Kyūbi still drew cautioned glanced and worried whispers. It was best to pretend the Kyūbi no Kitsune had died a long time ago, rather than reminding anyone it was still very much alive inside of him.

The sun was weak for this time of year, but Naruto welcomed the dull warmth. He had a temperature, only slight, as of late and it was nice to be out in the air. Why Sasuke hadn't suggested a walk or something was ridiculous. Naruto could hardly be held responsible, after all he was feeling sick and hadn't been able to even book a doctor's appointment.

Well, he could have. Sasuke wanted the bug thing gone and Naruto was comfortable resting at home. Their opinions had, yet again, clashed, but Sasuke had taken the high route this time, not allowed himself to fall to the brawl of idiots they were so fond of re-inacting.

Naruto would never quite understand his relationship with Sasuke. The sex was great, their companionship was great... but something was always missing. Even lying together at night, an invisible space crept between them. Naruto had heard their friends (well, Ino boasting to TenTen) talking about how nice it was to be held at night.

Naruto had never had that.

Did he want it? He wasn't sure.

On autopilot, Naruto had entered the minor accidents unit, smiling at the nurses. Here was where consultations were situated and they nodded, recognising him at once. It wasn't that often Tsunade came in for consults, but Naruto was always able to drag out the best in their Hokage.

"Uzumaki-san please," one of them called a moment later, directing Naruto to the door where he'd be diagnosed and cured.

"Hey Baa-chan," he greeted, smiling at his close friend. Tsunade smiled back, gesturing for Naruto to sit down.

"What's the problem then? That Uchiha visited me and demanded an appointment."

Naruto shrugged, feeling the barrier Tsunade had for Sasuke. It was deserved, after all, Sasuke had tried to kill Naruto in his (failed) attempt to leave for Orochimaru. She had never forgiven Sasuke for that, even after all these years.

"Well I've felt really tired recently. Not sleepy-tired either. I've slept so much these past two weeks yet it hasn't helped." Blue eyes watched as Tsunade typed something into the computer. "I've also been peeing a bit more. I haven't really been drinking that much more." Naruto paused, thinking what else could be significant.

"Toast makes me feel ill as well. I've also started liking vegetables, and you know I hate them."

Tsunade nodded absently, bringing her free hand up to Naruto's forehead.

"Usually I'd say this was a cold or something, but because it's you and it's been around for two weeks, I'll run some basic blood tests. Just to be safe," Tsunade added, smiling as she stood. A moment later, gloves were on her hands and she had the neccessary equipment to draw a small vial of blood.

"I'll run these through to the labs now and we'll get them back shortly. Do you want to stay here?"

Naruto could see that Tsunade would prefer to simply sit and chat and he nodded, grin in place.

"Why not? It's not as if I have any missions."

Tsunade nodded. "I was wondering, when you're better, if you could go on a solo-mission. It's extremely high class."

Naruto noted the change in Tsunade's tone and knew that this was something serious. There had been plenty of under-radar activity recently, but no one bar the very high ranking people on need-to-know basis had any idea. To be considered for something that was obviously linked to that was extremely rare for a normal ANBU such as Naruto and he wondered what exactly needed to be done.

"I don't like the fact that is has to be you, but we've considered all other options. If you're willing - and only if you're willing - Konoha wishes to send you to meet with the Akatsuki."

The Akatsuki, a familiar name to Naruto. They had been quiet for years, supposedly abandoning their previous goal of collecting the Bijū. Recently, though, they had been seen talking to numerous kages, attempting to pardon their members.

The reason behind their methods was unclear, and none of the other kages seemed to understand what was going on either. There had been reports that other nations had sent out people to talk to the organisation, but none of the reports had come back conclusive. In other words, the Akatsuki were nowhere to be found.

"If anyone..." Tsunade trailed off, unsure how to condemn Naruto to such a mission.

"Can do it than it's me. I understand Tsunade," Naruto offered a smile, excited at the possibility at being the one to crack the Akatsuki's shell.

"You dont have to-"

Naruto broke her off with a fierce look. "Konoha is my home, I love her. I know the risks, I knew them when I joined the ANBU. I'm the best person for the job and it'll be nice to get such an exciting mission."

That said, Naruto also probably knew the most information compiled on the Akatsuki. Never before had anyone else needed to know the sheer amount of information Naruto had to. Years spent away from Konoha had done marvelous things to the blond, training him in general skills. He had also undergone sage training, unknown to everyone except Jiraiya and Tsunade, the former because he had been at Myōbokuzan with him and the latter because she was the Hokage.

If anyone was prepared to take on the Akatsuki, it was Uzumaki Naruto.

"Tsunade-sama?" a voice called out from the other side of the door and Tsunade responded to let the nurse in. The lady walked in with a folder, smiling gently at Naruto as she did so.

"The test results have been confirmed and retests have been performed. All the information is in the file."

Tsunade arched an eyebrow slightly, wondering what it was that needed retesting. The nurse bowed once, leaving the room a beat later. Tsunade then turned to face Naruto, shrugging her shoulder.

"Let's take a look, shall we?"

Naruto nodded, literally on the edge of his seat. Usually they only ran retests for sick people, right? And even then it was odd unless you were really ill?

"What's wrong with me Baa-chan?"

The worry was clear in Naruto's voice, but he couldn't bring himself to care. What if he really had infected Sasuke as well? What if he was going to die? What if Sasuke was going to die?

"I need you to be completely honest with me Naruto."

Tsunade's voice was serious again, a professional tone to her voice. It couldn't be good.

"Y-yeah?"

"Are you sexually active?"

Naruto blinked, not expecting the question. Did that mean it was a sexually transmitted disease? Was it curable? What if he had HIV? He nodded, unable to form complete words.

"And have you... have you..." Tsunade paused, averting her eyes and sighing deeply. "This is going to sound like an odd question and I'm sorry, but we need to know." Naruto braced himself. "Have you had sex with... Sasuke," the name was spat out, as usual, "While you were in your... Sexy no Jutsu state."

Naruto flushed instantly, wanting to say no. He couldn't though, not really. It had been Sasuke's idea, five weeks ago. They had been out in the evening with some friends and had a little too much to drink. Someone had dared them earlier to kiss while Naruto was in his 'female form', and they had.

Sasuke had liked it, jokingly asking for more as they returned home.

Naruto had obliged with a foxy grin.

And then something else hit Naruto. It was a conversation months ago (maybe even over a year), where Sakura had pointed out the obvious flaws in his technique. She had been angry, again, at him for flaunting the female form and challenged his design.

So he had studied with her, pinpointing the differences between the human male and female. Bit by bit, Naruto had worked on changing the internal structure of his technique, visualising and feeling being a woman in a woman's body, rather than a man in a woman's body.

Without noticing, he simply added that knowledge when he transformed for Sasuke. All it took was a few chemicals activated, secreted in larger quantities, and Naruto had simply 'changed' the switches for the chemicals.

"So..." Tsunade kept her gaze away, unsure how to proceed.

"You were able to change the technique to alter the levels of FSH, LH and oestrogen and progesterone?"

Before Sakura's teachings, those words would have been alien to Naruto. Now, he simply nodded, understanding that the hormones Tsunade had just listed off had played a massive role in his life.

"It's amazing... how long were you able to sustain the technique?"

Naruto closed his eyes, gritting his jaw. If it was anyone but Tsunade, he would be furious. He wasn't an experiment, he wasn't someone who could answer to a beck and call... and yet he knew that was not what Tsunade was asking of him.

"A few hours at the most. The time had been getting better as I practised more. I was hoping that it would be useful at some point in the future... rather than sending a real woman out."

Tsunade nodded sadly; there had been a sudden influx in the rate of women who had come back from seduction missions and were unable to handle it. If Naruto could have gotten the upperhand, could have been a woman, at the time it was needed, he could simply change back. A woman was still a woman at the end of the day and while someone would be deterred at the sight of a woman turning back into a man, it would buy a fraction of time in which to complete the mission.

The longer a woman was in that position (and often they waited until the morning after, when the man was asleep and an easy target), the larger a danger posed was.

"You're tired you said?"

Naruto nodded slowly. "Yeah," he submitted himself to the knowledge his thoughts were on the right track.

"Can you use the Kyūbi's chakra?"

Again, Naruto nodded. "I guess it willl act as a boost?"

Tsunade reached a hand out, holding Naruto's palm in hers. "You can't use your own chakra as much as you have. It'll be hard... but the main reason you're tired is because your body needs to sustain the internal changes you made to the Sexy no Jutsu."

Naruto withdrew his hand, standing up and beginning to pace. Tsunade allowed him; it was a lot to take in after all.

"How did it happen? How could it happen? I just boosted the hormones... there shouldn't have been time!"

Naruto's voice had begun to rise, and Tsunade let him continue. No one would bother them, understanding that whenever Tsunade saw someone it would be important. First of all it had been because Naruto was like a son to her, but now it was because he had to face something completely unexpected.

"Yes, you boosted them. But you don't know how much you bosted them by. Say you overstimulated one of the hormones, the FSH. That stimulates the overall process. While it takes a normal woman around twenty-eight days, it could have taken you twenty-eight minutes. It just so happens that the time frame allowed for conception and so your body automatically adjusted itself."

Naruto looked like he was going to be sick when he looked up. "Why didn't I reject it?"

"It, Naruto?" Tsunade hated to be blunt, cold even, with him, but Naruto recognised she was trying to tell him that this wasn't just an illness anymore. "Why don't most people reject their babies? You're not ill, Naruto. You're healthy, perfectly normal, for someone who is expecting."

Naruto sat down, his face sinking into his palms.

"Pregnant," he whispered, minutes later. "Here I always thought it was only women who could get pregnant."

Tsunade scraped her chair across the floor, wrapping her arms around Naruto.

"You're having a baby," she whispered, smiling.

It didn't matter that it was caused through an accident and one of Sasuke's apparent kinks. It didn't matter that Sasuke was the father. It didn't matter that Naruto had been unaccepting at first. Naruto was going to be a father.

"A beautiful baby, Naruto. You'll have a proper family, you, the baby and," she paused, sucking in her lips a little, "Sasuke."

Naruto's eyes flickered to her and saw the moment Tsunade realised it had finally sunk in. He smiled cautiously, smoothing a hand over his flat stomach, feeling slightly odd that something (a baby!) was growing inside of him.

"Yeah..." he muttered, the smile spreading. "Yeah," he repeated, kissing Tsunade. "Thank you!"

He was gone a moment later and Tsunade shook her head. It would be a difficult process, especially as no man had been documented to have carried a child before (somewhere though, with all the techniques out there, it had to have happened), but Naruto would be the one, out of everyone, to pull it off.

Tsunade smiled as she wrote a memo to see Naruto, confirm future appointments and assign him a midwife. He'd need someone stabilising throughout the pregnancy, someone to be there constantly who knew what was normal and could offer explanations. Sasuke would be there for the emotional support.

Tsunade returned to her official offices, smiling at her close friend.

"Shizune," she began, rembering one of the many positions Shizune had taken up. "How comfortable do you feel on returning to midwifery?"

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Naruto felt as though he was walking on air, head in the clouds and all. Sasuke would be so pleased; he had an heir. While Sasuke had never breeched the topic, Naruto could sense the fact that the Uchiha line would likely end where it was hung over them like a dark storm cloud.

Naruto had entered into the relationship with Sasuke making sure that Sasuke had no illusions about what Naruto could give him. Naruto (well, had thought) would never give Sasuke a child, would never be content to just play the obedient, doting partner. He would love with all his heart, more than his heart even, but he would never be the typical housewife.

Sasuke had said he understood, with a smile, and had kissed Naruto properly for the first time.

Naruto slipped into the house quietly, wondering absently how he would break the news to Sasuke. It wasn't as though you could prepare for something like this, and Naruto was convinced it hadn't sunk in properly to him and he was the one carrying their child.

That was a scary thing to say. Their child. His and Sasuke's. He'd always have a piece of his best friend, lover, partner...

Naruto felt the tingle down his spine the moment he stepped out of his shoes. His eyes scanned the room around him, looking for signs of an intruder. There was a shirt carelessly thrown on the sofa, next to the blanket he had wrapped around himself the previous night. Maybe Sasuke was home and sleeping?

Naruto's heart plummetted as he saw the soft cardigan strewn across the arm of the sofa. It was clear that it didn't belong to Sasuke and he knew, he knew, what was taking place.

Sasuke wasn't with his team. He had booked an appointment with Tsunade knowing that Naruto would be out for a few hours. Naruto probably would still be with Tsunade if he hadn't wanted to prepare himself to tell Sasuke the news.

And now Sasuke was fucking someone in their bed.

Naruto didn't have to look far before the noises were apparent. The bedroom door was wide open, heavy moans escaping the room. Every now and again, a woman would draw in a deep sigh, before letting her breath out, and Sasuke responded eagerly.

He didn't have to look, but he wanted to know who she was. When he noticed the colour of her hair, it made sense, it really did. It stung, like millions of wasps attacking him at once, but if it was anyone, it would be Sakura.

Naruto brought a hand up to his stomach, fingers smoothing over the fabric of his clothes. He was going to have a baby, a baby-baby that wouldn't know Sasuke as the man its father loved. He would simply be Sasuke, the dad who had fucked it all up. Literally.

What was it that had drawn Sasuke to Sakura? They were friends - just - and Naruto had never sensed a spark between them. Sakura had never held any hint of being guilty, and he knew she would be. Could Sasuke have fed her some reason? But then why was Sasuke the only one that was getting the blame? What if Sakura had tempted him into it?

A confrontation was out of the question. Naruto couldn't deal with talking to them after all the information he had received in a matter of hours. First a baby, then a family, then the family ideals being shredded before his eyes.

Naruto glanced back into the darkness of their bedroom, seeing Sasuke's chest lower onto Sakura's, the pair finished. Sasuke took Sakura's lips in a gentle kiss, Naruto watching from where he stood as the couple smiled. They were acting like newlyweds.

Naruto had never been held like Sasuke was holding Sakura and he was about to slip away, unable to deal with anything else. That was until he heard Sakura's voice.

"I nearly didn't believe it when I saw the results of the blood test." Naruto froze, his heart beating madly. Had Tsunade somehow shown Sakura? "We're going to be a proper family." Sakura kissed Sasuke tenderly and Naruto winced.

Sakura was pregnant. Sasuke would marry her, leaving Naruto alone. After all they had sworn, after the effort Sasuke had gone to to get Naruto to be with him...

As much as Naruto geniunely wished he could be happy for them, the fact that hello he was here first rang through his mind, pounding against his skull.

He had to get out of there.

Naruto turned, leaving his things behind and Sasuke with his new lover. He felt like crying, deep inside, but there was no energy to cry. Sasuke's child, rooted deep inside his oddly deformed body took all of his energy, and as much as he wanted to hate the baby inside of him, he couldn't.

With a hand still covering his belly through the t-shirt he wore, Naruto left a note, propped almost lovingly against the fruit bowl. He took a single apple, biting into the flesh and leaving their home.

He'd go back to Tsunade. He'd go on his S-classed mission, baby or no baby. Sasuke wouldn't hold him back this time. He'd become sick of sacrificing himself.

Naruto forgot that sometimes tears didn't listen to rational reasons and instead bypassed straight to that shitty feeling called love, clouding up his vision.

He didn't cry, though. He couldn't let Sasuke have that much from him.

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Notes:

This was adopted from ShortFogHornXD who has since taken it down.

A note on the mpreg here: yes it is part of the story, but it's not the entire story. Yes the pregnancy and the baby do play a big part, but it's a lot bigger than that :)

Thank you very much for reading, reviews are always appreciated.