Disclaimer: See chapter 1

Chapter 18: Sirius Black Gets a Biology Lesson

They continued to discuss the issue of having a child over the remainder of the holidays, almost to saturation point. There had been some emotional disclosures between the two men regarding their strange and abusive upbringings but by and large a decision had been reached; they were going to become parents.

They had chosen to embark on it sooner rather that later due their respective ages. Although they weren't old in wizarding years; male pregnancy had a tremendous impact on the carrier's physiology and this required the male to be in excellent physical health, which Sirius was.

He had long since recovered from his time in Azkaban and being on the run. So, they had decided to strike whilst the iron was hot.

Severus explained the ins and outs to Sirius and what the process entailed.

"The Conceptioni are extremely complex potions but the Vir Conceptionus is particular unforgiving in its use. Most potioneers who brew it have been unable to adjust its formulation, leaving many wizards pregnant despite changing their minds."

"I don't get it, why would they become pregnant if they decided not to go ahead with it?" Sirius queried.

"Well that's why there's so little room for error with it. Fertilisation is induced magically and conception is guaranteed immediately after ejaculation in male pregnancy. Therefore, all forms of contraception are useless against it, both magic and muggle. The combining process in female pregnancy does differ significantly as women are not natural depositors during lesbian sexual relations but the principle is the virtually the same."

Sirius look even more perplexed.

"Look, it's quite simple." He said, slipping into teaching mode. "In heterosexual conception you need sperm and an egg right?"

"Dah! That much I do know."

"Well, think about it. In homosexual conception, you have an egg and an egg in lesbian conception and sperm and sperm in the other and never the genetic material shall meet. Right? " He deliberately misquoted.

"Right. Gotcha so far."

"Wrong! You see, both the Vir and Femina Conceptionus potions extract the genetic material from the opposing donor, i.e. you, as you don't have any ova being male. It then combines it magically with the opposing partner's DNA, to create a blastocyst. From there on in, development of the foetus is exactly the same as in a naturally occurring pregnancy."

"But what about a womb in men?"

"Now that's where the two potions differ. Obviously women already have a womb and therefore have no need of additional one. Whereas, the Vir Conceptionus actually creates a male womb that self secretes the necessary pregnancy hormones to sustain the pregnancy within the abdomen when ingested by the intended carrier." Severus explained.

"It grows off the sigmoid colon and the rectum acts like the vagina; sealing off temporarily so that sperm transmission can occur in the newly grown womb. After, because of its location, the womb seals itself off to prevent contamination, much like the mucus plug does in a female pregnancy and then the rectum simply reverts back to normal straight after copulation." He continued.

"Merlin's hairy gonads!" Sirius exclaimed. "You turn me on when you talk so clinical. You know I never did get you to recite that speech you gave the day I proposed to you. I really could do with hearing it now, preferably with my prick in your mouth as you do it." Sirius said jokingly; his eyes reflecting the lust he was currently feeling.

"Dickhead!"

"Damn straight. This dick does want some head!" He rubbed his groin suggestively.

"Are you going to let me finish explaining or are you going to just sit there, rubbing yourself up and thinking about sex?"

"Can't I do both?" From the look in his husband's eye, he already had his answer. "Anyway, how come you know so much about it?"

"Because my darling husband, you may not be aware but in order to generate an additional income, I happen to brew privately for a select number of commercial clients. Furthermore, it just so happens that I've been brewing this particular potion for a few of years now."

"Of course you have." Sirius said matter-of-factly. "And when you said that most potioneers have been unable to modify its formulation, I take it that you didn't include yourself in that category?"

"Naturally, I registered the patent with the Ministry, along with a number of others. I modified it so that an incantation must be invoked to activate it prior to intercourse. Ergo, no incantation, no pregnancy. However, there are other risks that no amount alteration to its formula will prevent."

For the first time, Sirius' happy-go-lucky attitude about the pregnancy appeared to slip slightly.

"What risks?" He asked seriously.

"Well, the most likely is the one that we've already discussed; the impact the pregnancy will have on your physical health."

"And the others?"

"Like any other pregnancy there's always a risk of miscarriage. However, the main one in male pregnancy is that there's a one in four chance you could lose the baby due to genetic incompatibility."

"Why so high of a risk with male pregnancy?"

"The genes it receives from its parents determine its sex and as you know the sex of a child can only be male or female; XY for male and XX for female. Ordinarily this doesn't present a problem, although a lesbian couple can only create a female child, as their genetic material is inherently female. But when the parents are two males then there is a 25 percent possibility of the genetic combination of YY. There isn't a viable YY combination and therefore an embryo with this make-up will spontaneously abort."

"Oh." Sirius said unusually sombre.

"Yes, and it can take the carrier up to a year to fully recover physically and begin the process again."

"Isn't there anything that can be done to prevent it?" He enquired, a tad more hopeful.

"No, nothing. It's merely luck of the draw I'm afraid." Severus didn't miss his husband's shoulders drop in defeat at this final bit of information. "But I'm sure we won't be affected. You'll see Siri, and you're missing the most important part. There's a 50 percent chance we'll have a happy healthy son and a 25 percent one of having a daughter." He said, in a show of uncharacteristic optimism.

"Yeah, I suppose you're right."

Severus was perturbed at Sirius' reaction to the possibility of the pregnancy ending in miscarriage. Despite loving the man to distraction, he'd always thought of him as a rather shallow individual. He now felt distinctly guilty about this.

Sirius had repeatedly demonstrated to Snape since they'd been together that he was capable of deep feelings and he had continued to dismiss them, or at the very least, ignore their existence.

Not quite sure how to deal with the somewhat deflated animagus; he did the only thing at his disposal and what usually cheered him up.

Sex.

"Come on you old dog, cheer up. I'm pretty sure that I can remember that speech word for word." He cajoled.

Sirius' lips quirked upwards, as he failed to suppress his mirth.

"And you know, you only heard the abridged version; the unabridged was at least another fifteen minutes longer with all of the Ministry's statistics included." Severus added wickedly.