http://archive.heinessen.com/mlp/thread/17600690#p17605507

The Festival of Fertility, it only happened once every 2 years, but it was insanely popular. Ponies from all around Equestria gathered to Canterlot to thank the Princesses for the abundance of crops, the increase of livestock and of course, the joyous pregnancies of mares and the abundant emissions of stallions.

For a week, Canterlot was in colours. Heavily pregnant mares trotted the streets, where they were treated as godesses, with offerings of free foods and tummy rubs for good luck. It wasn't rare to stumble upon mares in heat getting rutted by random stallions in the hope of being impregnated, or of mares going in labour and public and bringing their foals into the world in front of everyone else.

The Festival was nearing its end, where the Princess of the Sun herself would grace Canterlot with her presence. There had been rumours her presence at this festival would be particular, as the Princess hadn't been seen in public. Ponies were talking, and they were very excited to see what their benevolent alicorn ruler had in store for them...

...they weren't going to be disappointed.

''Your fertile Highness, is everything alright?'' asked Sunrunner, her loyal little pegasus midwife. She gave a kiss on the fertile, enormous royal tummy, making Celestia moan.

''It's... it's nothing Sunrunner. Labour has... started. And our little heirs are getting restless. They want out soon...''

As if on cue, one of the foals kicked, making Celesti'as belly ripple. She moaned loudly, and Sunrunner tried to soothe her mistress's pain with renewed kisses.

''Oh Sunrunner, you have been of great assistance these last 11 months. Soon, my foals will finally leave my womb, and I will need you once more. Are you ready?''

''Oh Princess, I expected this days for years. I am ready to assist you.''

Knowing full well her duty, she scooted under Celestia's heavily bloated tummy, going straight for the Sun princess's milking crotchboobs. Celestia gasped in both pleasure and pain as she simultaneously was hit by a hard contraction and the feeling of Sunrunner's lips on her nipples drinking milk from her.

''Ah... Sunrunner... nnnghhh... leave some for the foals would you...''

''But of course, Princess'' Celestia could detect a hint of deviousness in her tone, and she wouldn't regret what she said.

Sunrunner had the brilliant idea to switch to Celestia's marehood, carefully teasing the alicorn's plump vulva with her mouth. Nearly immediatly, Celestia's juices flowed and she gasped in pure bliss.

''Oh... oh YES. YES! Please! Keep going! And... ah... rub my tummy!''

Sunrunner wasn't one to disobey orders, especially not from the sun goddess. She stretch her hooves, trying to grab as much of the wide, royal pregnant tummy as she could while still licking the most precious part of Celestia's anatomy.

As for Celestia, the combination of her churning belly, the movement of Sunrunner's hooves and the delicate attention from her tongue soon proved too much to bear. With such sexual bliss coursing through her body, she could ride her increasingly painful contractions without any problems.

''Oh gosh she smells goooooood'' thought Sunrunner. The smell of Celestia's pregnant pussy would have driven a lesser pony feral with lust, but constant exposure to Celestia's hormones through her pregnancy had made Sunrunner slightly able to resist it, emphasis on slightly.

''F... fuck, this feels so fucking good. I'm gonna cum Sunsun... oh fuck YES!'' shouted Celestia. Her orgasm was approaching and she could feel it, but she never had the chance to experience her release. A Royal Guard had bursted into her quarters.

''Your majesty... it's the crowd. They are growing restless, they want to see their princess, you understand?''

Celestia's leg quivered from frustration and she sighed. The guard did have a point. Her contractions were becoming more and more frequent... and more and more painful. The birth was nigh, and her waters could burst at any moments.

She wanted to give birth in front of Equestria. She wanted them to gaze as her water broke and she pushed the royal foals out of her body.

Celestia trotted slowly, as fast as her enormous belly allowed her, out of her quarter and into the stage she commissioned for the occasion. Sunrunner was in tow, along with two token Royal Guards.

When the ponies of Equestria saw her, they positively burst into joy and applauses. She raised her hoof and waved back at them. Equestrian ponies were smart. They knew why their pregnant princess was on stage. And they wanted to see every second of it...

''People of Equestria! You are all incredibly privileged. Today is the closing of the Festival of Life, and you will see your beloved princess bring royal heirs into the world for the first time in centuries!''

''I want the whole of you to gaze upon my glorious plot as it births my foals. I want you to stare at my body as it is wrecked apart by contractions'' Celestia's magically amplified voice reached trough the crowd easily, and the ponies present absolutely roared with approval. They applauded madly, wanting more.

Celestia turned around and lifted her ethereal tail slightly, presenting her pregnant cunt to the world. The next contraction came, and with it, something gave inside Celestia and water rushed out of her vulva, wetting her hindlegs and falling on the floor as Celestia moaned in surprise.

''Yes... YES! My waters have broken Equestria! Ah! The birth is... gah!... imminent!''

The crowd went absolutely mad. The whole Festival had been an absolutely insane orgy of sex, impregnations, estrus and birth and now, to top it off, the sexiest mare in Equestria would push as hard as she could, in front of everyone, to get her babies out of her pussy.

It was like winning the lottery. Stallions in the crowd now sported raging erections while mares were so wet you could have sworn they had sprung a leak.

Celestia gritted her teeth. With the waters gone and her cervix fully dilated, there was nothing but the tightness of her vagina holding the foal from the outside world. Already, the first baby's head was pressing hard on her cervix. The pressure was unbearable, almost painful, and yet... slightly pleasuring.

''Sunrunner, please... rub my belly. Kiss it.''

Eager to please, the little mare rushed to the enormous sides of her mistress, smothering it with kisses and lickings. It brought pleasure to Celestia, who could now focus entirely on pushing the baby out. Already, she could feel it slowly, slowly, slowly sliding down out of her, overcoming the resistance of her flesh.

''People of... aaaah... Equestria! I can already feel the first one coming out! It's tiny body slowly sliding out of me! Gaze upon me! Watch it enter the... gaaahh... world!''

The little baby's head was already crowning, stretching Celestia's tight vulva to the breaking point. Her moist fleshy walls could barely hold the squirming baby, and the princess could feel every kicking movement of her foal, desperate to be free. The pain was hard, yes, but the pleasure was beyond her imagination. She tried to visualize her foal's head as an enormous dick giving her a good rutting.

''Oh yes! YES! PLEASE MORE!'' she moaned. The audience was beyond horny. Stallions with raging boners whinied as they felt their release. Some turned to other mares they didn't know and mounted them, with no resistance, the mares being more than happy to get a nice big dick in their wet pussies. Hundreds of stallions came at once in wet, waiting vaginas, drawing moans of pure bliss from the mares and repeating the cycle of impregnation again and again. The thought of being impregnated by complete strangers made them even more horny.

Celestia mentally prepared herself for the big, final push. Her foal's head was already fully outside, and she was beyond aroused.

''Sunrunner, prepare to catch my... aahh... my baby...''

A contraction came and she further spread her legs involuntarly. She gathered her strength and pushed, pushed as hard as she could, moaning all the while. She felt the baby move out of her then completely leave her body with a pop. Her orgasm finally came, coursing through her body, driving her mad with lust.

''OH FUCK YES THIS FEELS SO GOOD! OH FUCK OH FUCK YES!''

She raised her head and closed her eyes, gritting her teeth as she savoured the orgasm. The little cries of the foal were drowned out by the orgasmic moans of both her mother and the crowd.

''Sunsun... more... more foals are coming... prepare to grab them... and please... keep rubbing my belly''

''As you wish princess''

Sunrunner draped the little foal in a blanket, then took back her place at Celestia's side. The princess panted heavily as contractions already resumed.

Already she could feel the second foal engaging its head in her cervix as its little brothers and sisters still inside kicked a fury. She moaned to the crowd

''Equestria! This.. this isn't even over, there are... aaaah... still... more... babies inside of meeeeee! YES! OH YES! I CAN ALREADY FEEL IT COMING OUT!''

And that's how Equestria's heirs were born, in thundering, public orgasms.