Anatomy

Clinical descriptions of genitalia.

Anatomy At Birth

Sex is more difficult to distinguish, people discovering a different gender at puberty is more normalized.

Sexual characteristics exist on a continuum.

Most people have a vulva and a penis.

Females usually have a small penis/enlargened clitoris at birth, but some may have full penises. No seperate clitoris and penis, both develop from the genital tubercle in our world

Males usually have a shallow vagina, and often their labia aren't fully developed, but some have full vulva and vagina

Colloquially called "true alphas", about 0.2% of males have no vulva at all, with the skin between penis and perineum being smooth, having ridges to mark where the labia major would be, or even having a slight scrotum. Testicles sitting in an external scrotum is EXTREMELY rare. These men are all betas or alphas.

Males are not born with uterus or cervix

Urethra usually in penis for males, in vulva for females, but partially up the shaft isn't uncommon

Labia major usually exist in both sexes, but labia minor may not be present in males, or only exist around the front of the vulva

The urogenital folds need to develop into both the labia minor AND the skin of the penis - in our world they get to choose one

Similarly, both the prostate (squeezes urethra to block pee during erection, and produces some parts of semen) and skene's glands (lubricate urethra so you can pee) develop in anyone with urethra outside of penis

Vas deferens (duct for sperm) and fallopian tubes (tube for eggs) usually both develop for all sexes.

The slick glands are the only organs unique to this world. They replace the bartholin's gland in lubricating the vagina, freeing that to develop into a cowper's gland (which produces pre-ejaculate in the penis) for all sexes.

Puberty and Presentation

Everyone goes through puberty, alphas and omegas also experience presentation.

Puberty almost always happens first, though some male omegas may experience them near-simultaneously.

Females grow breasts during puberty. Males' penises grow. Everyone gains body hair. Men gain more, and start growing facial hair. Menstruation MAY start, with most betas, some omegas, and a few alphas menstruating. It will usually dry up again if the person presents. Presentation tends to start earliest for male omegas, since they have to grow an entire uterus. Some start as early as 9. However, if they're dealing with food insecurity or other challenges, presentation may be delayed all the way until adulthood.

Male omegas grow pronounced uterine horns, and gestate children there, rather than in the body of the uterus. The horns aren't spacious enough for a full size human infant (a singleton), but are big enough for the smaller sized infants in litters. Male pelvises (like in our world) tend to have a narrower opening and a steeper angle than female’s. While they do become elastic in pregnancy (like humans), they’re usually still too narrow to give birth to a full-sized baby. This is another reason singleton births are dangerous.

Male omegas do not usually develop breasts, instead growing two sensitive columns of mammary tubules under the skin of their chests and stomaches. If they become pregnant, these will develop into dugs (the term for nipples if you have more than 2). (They may also develop for a variety of other reasons, like a hormone spike or being around other people’s infants, and sometimes seemingly for no reason at all.) A pregnant male omega may develop anywhere from 6 to 10 dugs, which will only protrude slightly (no bouncing boobies) but will be longer than female nipples. These dugs are permanent, though they are much less prominant when the omega isn't lactating.

Some female omegas also have these columns of tubules that may (or may not) develop into dugs. In all sexes there are considered erogenous zones when present.

Female alphas' uteruses will often wither, and even be reabsorbed, if they have them. (This can sometimes lead to medical issues, and hysterectomies are reasonably common.) Vaginas tend to become shallower leading up to presentation, and are usually too dry for penetration to be pleasant without a lot of added lubrication.

The gonads develop during both puberty and presentation, depending on orientation and sex. Female alphas' testicles don't develop during puberty. Some male omegas may get ovary development during puberty, but it's uncertain if this is actually due to early presentation. During puberty, gonads develop along similar lines to our world - singular eggs each month in ovaries (for female betas and omegas), steady sperm build up in testicles (for male alphas and betas). However, gonads may stay undeferentiated (able to become an ovary or a gonad) for much of childhood. In exceptional cases, differentiation may not happen until presentation in female alphas and male omegas.

During presentation, development changes. Ovaries (in all omegas) build up stores of eggs to release during quarterly heats. Sperm production in (all alpha) testicles starts to vary - slower in some periods, and then extremely heavy in others, allowing alphas to better match omega heat requirements. The make-up of semen during these heavy periods is different, as well. It contains hormones designed to jumpstart cellular growth. Eggs fertilized outside of heat will usually stay in the fallopian tubes/uterine horn until sex during heat allows them to soak up enough hormones to jumpstart development. (This means that a litter with multiple different sires is possible, though fertilized eggs may have decreased receptivity to seminal hormones from a different sire. Research is still ambiguous.)

For omegas, pregnancy outside of heat is unlikely, but possible. (This is not applicable for betas, who don't go into heat.) Fertilized eggs are usually lost if the next heat doesn't include sex. But singleton (one child, like our world, with the same possibilities for twins, etc) eggs may develop without seminal hormones. This usually begins immediately after conception, when the eggs continue to the uterus rather than staying put.

Male betas beget singletons. Female alphas only beget litters. Male alphas can do both, though litters are more likely with an omega partner. Female betas also only give birth to singletons (though they may have increased conception rates during the heavy part of their partner’s cycle), and while they CAN gestate only a single child from a litter, will usually have lower conception rates with female alpha partners. Male omegas can concieve singletons, but their uterus isn't designed for them and singleton pregnancies are often lethal.

Both male and female alphas' penises grow during presentation, and they develop a knot. Since male alphas experience two periods of penile growth, they usually have the largest members. Female alphas tend to have shorter penises, but may have similar girth.

Slick production starts during presentation. (Slick glands and knots are the only parts of Omegaverse genitalia not present in humans). Before presentation, all sexes produce minor lubrication from these glands - enough to keep the vagina from drying out. But during presentation, these glands proliferate in omegas, lining the entire vaginal wall to provide lubrication for multiple days of heavy friction. While male omegas tend to present first, female omegas tend to present last. Female presentation of all types tends to be in the late teens, with some females reaching early twenties before knowing their dynamic.

Male alphas don't have a 'normal' age of presentation. Presentation can occur anywhere between 12 and 22, with mid-teens being considered 'average'.