"Just because you could be pregnant, doesn't mean you necessarily are."

Deb Lister's words echoed around her head. She'd never know. Dave, her male self from another universe and possible mother of her child and gone back to his own dimension. Lister watched the emptiness of space fly by as the Red Dwarf cruised along. On the other side of the universe, or under it, or above it, or inside, outside - whatever! - Dave Lister could be carrying a baby. A baby that would be in all retrospect, a clone of them. What a bizarre thought. "S'up dudes?" Hilly's new male head appeared on the wall.
"Nuthin'." Lister pushed herself away from the window and took a cigarette out of her ear and lit it. "Just thought you'd like to know that they're back."
"Who?"
"The other Red Dwarf." Lister nearly swallowed her cigarette in surprise. "Y'wat?" she squeaked. "S'only bin 4 hours since they left!" Arleen Rimmer marched into the room with the Dog in quick succession. He jumped onto her bunk and began to nibble at the fleas on his arm. "NO! Bad Dog!" Rimmer snapped. The Dog stared up at her with his biggest and saddest eyes but it was no use. He slunk off the bed and chewed his arm on the floor instead. "I think I gots me a tick!" Rimmer ignored him. "Lister, do you remember the future echoes?"
"Yeah."
"When we saw your future self with those two men and you told yourself they were your twin sons?"
"Oh yeah! Wow, Dave has twins? Poor guy." Lister scratched the back of her neck guiltily. Rimmer shook her head, "Didn't it strike you as odd? That they were 20ish and you looked the same age?"
"Clit, you're right! What the clit's going on?" Lister asked Hilly. Hilly told them he'd go and find out as soon as he could get a link with Holly again. He was looking forward to that indeed.

When Dave Lister discovered he was pregnant, and most likely with twins, he reacted as anyone would. He dug himself into deep denial and moped around in disbelief. Just not possible, he reassured himself. Utterly impossible, he reminded himself again. He'd had drunken unprotected sex before, what could be the chances of an accident happening after a 3 million year break? Apparently very high. Rimmer was thrilled. "Scum," he grinned. "It's despairing living with such a sex-fiend."
Lister groaned on the bed, "Why me? Why smegging me?"
"Because I was smart enough to run away from my parallel self, instead of getting blitzed and sleeping with her."
"Shut up." Lister turned over grumpily, his hormones already raging it seemed. Rimmer called Holly up. "Allo," she said. Rimmer rubbed his eyes. He'd never get used to a female Holly. "Holly, Arleen sent a few files through your system before we left. Link them up to voice activation and see if you can make a hologramatic version." Holly gave the files a small virus scan. "Oooh very nice," she said. "You're taking this very seriously." Her face vanished and the screen was left with two animated directories with paper flitting from one to the other as they downloaded. "Wassat?" Lister asked curiously, turning back over.
"'Dr. Watson-Smyth's Guide to a First Pregnancy: Platinum Edition'. Highly recommended." Lister groaned. Rimmer was researching pregnancy, which meant only one thing: He planned to commit to this 100%. And that, Lister knew, was a scary thing.

Rimmer read 'Dr. Watson-Smyth's Guide to a First Pregnancy: Platinum Edition' several times. He knew it like he knew his 'Risk' game logs. He wasn't sure why he couldn't put the same effort into his astronavigation exam revision. But now he was pretty confident that, when the time came, he could help Lister through any birth. He'd finally be useful. "Rimmer? What are these red notes?" Lister said as he eyed the calendar hung on their wall. Rimmer pointed at various parts and explained them to be his diet and exercise codes. "My what?"
"EXF - Extra Fibre. FA - Folic Acid. And at the bottom here; NO RAW EGGS, HOT CURRY OR ALCOHOL." Lister felt ill. "Not even a slightly hot curry?" he said, his voice a whisper with shock.
"Trust me Lister, you won't WANT one. But if you must, maybe just once a month. I think it'd be best if you avoided spicy food altogether. Or you'll get terrible heartburn and indigestion. And foods with strong smells and flavours will either send you to heaven or the vomitarium."
"Bu-"
"Not my fault. Blame Dr. Watson-Smyth. And your sex drive for getting you in this mess in the first place." Lister groaned and sank into his bed. He already felt peculiar. Like his entire body was hijacked, not just his... uterus? He didn't have a uterus! "Rimmer? Where do they grow?"
"Where does what grow?"
"The babies. Where are they?"
"In your testicles." Rimmer didn't look up from his book but he could swear he almost heard Lister's jaw smack against the hard, cold floor. "Me WHAT?!" Rimmer flicked a few pages back to the chapter on conception. "During intercourse when the man's penis enters the woman's vagina, the egg swims down to meet the sperm."
"The egg swims? I thought the sperm did."
Rimmer cleared his throat, "They both do. They fertilise inside the woman and travel down the penis to the testes where the embryo begins to develop" he grinned evilly at Lister's terrified face. "They don't STAY there, do they?" He tried to picture walking around with two fully grown babies hanging in his goolies. Rimmer snorted with laughter. "Don't be stupid, Lister. They make their way up at around the 5th week and nestle snugly on top of your bladder, causing you much discomfort," he said the last few words with great pleasure. Lister looked down at his boxers in wonder for the first time since he was 12. "But what about a womb, Rimmer? They need a womb!"
"It's actually very fascinating, Lister. It's a cross between marsupial and bird reproduction. The fertilised egg when in the woman gains a protective skin like a bird's egg before it gets a shell. It's like a thicker version of a placenta. With me?"
"Not really."
"Good good. But instead of getting a shell and being born as a bird egg, it attaches itself to the side of your stomach and eventually gets food, blood, and waste relief from you. Doesn't take too long to develop all those connecting bits and bobs. Just like a marsupial baby. But without a pouch. Understand now?"
"Y... no."
"Didn't expect you to. I don't really get it either." Rimmer put the book down. "So, we have much vomiting, stomach pains, backaches, swollen limbs and moodiness to look forward to. Excited, mum?"
"Smeg off."

Author notes;
Clit - the alternate universe form of 'smeg'. Vaginal discharge didn't have the same ring to it
The egg/marsupial theory - I went through several ideas for how a baby could survive without a womb but most of them involved going down the route of Lister not actually having the babies himself. And the testicle thing was just a late-night giggle I had over the fertilisation process and it somehow stuck.