Good sex is one of the ultimate pleasures we can give to another person — and to ourselves.

Touching, licking, sucking, pounding, stroking, biting, pulling, grabbing, and finger — banging are all awesome — at least they are when our sexual equipment (and the equipment of our sex partner) is functioning correctly.

When things aren’t working right, be it a new problem (like impotence) or an issue that’s been there since birth (a micropenis, perhaps — yup, official medical term), we call it pathology, and that’s my field. I am a board — certified pathologists’ assistant with over 16 years experience working in the hospital laboratory and pathology departments. And through the years I’ve seen some shit.

Before we can understand the pathology of sex, we need to establish the baseline for what’s considered normal. Plus, knowing the male and female anatomies is one of the ultimate powers one can hold in the bedroom. The more you know, the more fun you can have.

Let’s start with a little Sex Ed 101.

Under normal circumstances, the penis is just hanging out, minding its own business until it gets stimulated (which seems to be often). We call this a hard — on, a boner, a stiffie, and so on. Mechanically, what transforms a penis into an erection is blood flow into a pair of hollow cavities called the corpus cavernosum. Distended, these cavities make the penis hard and ridged for penetration. There’s also another cavity called the corpus spongiosum. This one swells with soft spongy tissue and houses a tube called the urethra, which is the way a guy ejects pee and semen from his body.

Speaking of semen, I’ll never forget when a female classmate in my seventh — grade Sex Ed class raised her hand and asked, “What is come?” I can’t remember the teacher’s reply, but here’s how I would answer: Sperm — the little cells that look like tadpoles — are made in the testicles. Sperm travel up the vas deferens to the prostate gland where they meet the seminal vesicles and merge with vesicle fluid. Bingo, come.

During sexual climax, a man’s eyes roll to the back of his head, he has a small seizure, and we ladies get to see the big show. Or to put that more scientifically: After a man experiences orgasm, semen exits the urethra of his penis.

As for women, we don’t need stimuli (although it’s nice) to be ready for sex. Our hole is always open, as I like to say!

The female genital tract has one thought on its mind: Make a baby.

Every month the ovaries and uterus work hard to create the perfect baby — makin’ environment. The uterine lining builds up. The ovaries release an egg. That egg either becomes a baby or it doesn’t. If it’s fertilized by a sperm, pregnancy occurs. If the egg is not fertilized, it will be discarded along with the new uterine lining. This is called the menstrual period. (Women know it as hell on earth.)

During male orgasm, semen shoots up the vagina right into the cervix, a portal to the uterus for sperm and an exit hole for a baby or period blood. Once in the uterus, sperm start looking for the egg. One lucky guy might find it, whereupon the egg gets fertilized in the fallopian tube. The fertilized egg divides, travels out of the tube, and plants itself into that cozy new uterine layer. This is the spot where the growing embryo will turn into a fetus over the course of the next nine months.

As for female orgasm, it’s not a functional process as with men (their willies are sperm — shooters, orgasm the trigger) but rather a “sensational” process. It causes sensations.

(Indeed, it does.)

While we’re on the subject of female anatomy and sex, let me just say that I will not be exploring the phenomenon of big tits, big lips, and big asses. These aspects of female anatomy have a strong cultural, as opposed to purely biological, dimension. In some cultures breasts are for babies to enjoy. In others, motorboating. To each his own.

Humans are animals. As animals, our sexual anatomy is designed for baby creation. That said, we as a species have a highly evolved intelligence (even if it doesn’t always seem that way). We can think things through. We weigh actions and make decisions, even when it comes to sex and baby — making. Just because we are designed to procreate doesn’t mean we have to.

The most effective form of birth control is abstinence. Yeah, that sounds fun! Fortunately, for those of us who actually want to enjoy time in the sack without pregnancy, we have options.

Birth control — wise, surgery is highly effective. A doctor cuts the tube carrying the sperm or egg and the two can’t meet. In men, the vas deferens gets snipped. Hello, vasectomy. The vas is in the scrotal sac, easily accessed. A woman’s option is more invasive: tubal ligation, aka getting the tubes tied. A doctor enters through the woman’s belly and snips off all or part of the fallopian tube, ending egg transport.

Globally, about 20 percent of women use hormones to prevent pregnancy. Birth control pills were the first method, introduced in the sixties. “The Pill,” the patch, the ring, the injectable, and implants all work by preventing egg release. Hormones also thicken mucus around the cervix so the sperm confronts a barrier.

Implantables include IUDs — intrauterine devices — and fallopian tube clips or coils. I’m not of fan of devices unless they are 100 percent medically necessary. When the body recognizes something as foreign, it has one objective: get this thing the fuck out of me. It creates barriers to protect itself. That’s when trouble can start.

In theory, an IUD sounds awesome, but complications can be nasty, including infection, bleeding, cramping, and the device getting stuck in the uterine wall, possibly gouging it. The pill, too, can cause complications, including strokes — especially in smokers — but such outcomes are rare, and if it slightly raises the breast cancer risk, it decreases ovarian, endometrial, and colorectal cancer risks.

Condoms, the sponge, and diaphragms are non — hormonal, non — surgical, and operate as physical barriers. Sponges cover the cervix and carry a spermicide. It’s pretty effective if used properly. As for the diaphragm, it’s almost like a short, wide condom for women. It covers the cervix, blocking sperm. It’s better than nothing but not especially effective.

The pull — out method is my favorite form of birth control! Unfortunately, it’s also the least effective. But if you like to feel your partner’s skin, this one’s for you. Moreover, it makes sex a little more dangerous and exciting, don’t you think?

PSA: Even when a woman has her period or is breastfeeding she can get pregnant. When Jeff Goldblum in Jurassic Park said, “Nature will always find a way,” he was dead — on. There are documented cases of pregnancy in women using each birth control option above. It takes just one sperm and one egg to make a baby!

Humans are one of the few species that enjoy sex for pleasure. Who else? Dolphins, chimpanzees, and penguins, among others. Penguins are total WHORES. These horny birds partake in gang — banging, multiple partners, homosexuality, even rape.

“Some people are born with ambiguous genitalia. Some grow up feeling like they were born in the wrong body.”

So now you know the machinery and its basic functions. But just like ingeniously designed iPhones have glitches, our super — sophisticated sexual bits can have performance and configuration issues. We can’t all be flawless. Normal’s not fun anyway. More importantly, the abnormal is what keeps me in business!

Some people are born with ambiguous genitalia. Some grow up feeling like they were born in the wrong body. This is nothing new, but it’s more accepted and recognized now. Is it a boy? A girl? In the twenty — first century, these questions are more complicated, even if human biology hasn’t changed.

Under normal conditions, sex is determined at the time of conception. Mom’s egg meets Dad’s sperm and the result is a shared genetic makeup called the genotype. If you are a girl your genotype is XX, and if you are a boy your genotype is XY.

In early fetal development, males and females look alike. But males have a gene that causes testicles to grow. Testicles release hormones, which turn a male into a male anatomically. Without these hormones, a female starts forming female sex organs. This is called the phenotype. A phenotype is when we look at a person and determine their sex based on anatomy — a penis and scrotum for a male, a vulva and vagina for a female.

But some of us humans aren’t clearly male or female. Our term for this is “intersex.” It can be a genotype issue (the fetus not neatly XX or XY), a phenotype issue (both male and female sex organs present at birth), or a combination. Nature hasn’t decided the sex. At some point the parents, child, and/or doctors must make the call.

Klinefelter syndrome and Turner syndrome are two of the conditions that can alter the genotype. Klinefelter occurs in males, and it’s when a man has an extra X chromosome. He looks like or has the phenotype of a normal male, but after puberty he won’t have sex characteristics like body hair. His semen contains no sperm. Turner’s only occurs in females, when a woman is missing an X chromosome. Phenotypically, she looks female, but she is short in stature and can’t have children.

It’s human nature to identify with male and female phenotypes. Some conditions in which phenotypes are abnormal or don’t match the genotype include aphallia (male born without a penis), clitoromegaly (female with an enlarged clitoris), micropenis (male born with a small penis), partial or complete AIS (androgen insensitivity syndrome), and CAH (congenital adrenal hyperplasia).

Complete AIS is usually inherited. It blocks a body’s cells from responding to hormones. In the AIS fetus, testicles grow, but the male sex organs (penis, scrotum) do not. And since testosterone prevents a fetus from growing female sex organs and the AIS fetus does not respond to this hormone, the organs differentiate into a female. AIS babies look like females, but have male DNA and internal testicles. These people cannot have children.

CAH or congenital adrenal hyperplasia causes unusually high levels of hormones. A female with normal chromosomes develops male sex characteristics such as body hair, a deep voice, and a clitoris that is enlarged or resembles a small penis. Men can have this disorder, too, but it does not cause ambiguous genitalia.

The term “hermaphrodite” has now been changed to “intersex” because a hermaphrodite in any species can act as both a male and female AND has the ability to self — procreate. Since this is impossible in humans, we changed the term.

In the past, parents of intersex children picked a gender for their child and surgeries and hormone treatment followed accordingly. Today it is advised to let the child accept their body and allow them to make their own decision as they get older. This way, the individual can chose the gender they most identify with.

We hear the word “transgender” a lot these days. It’s a broad term describing individuals who feel their gender identity differs from what they were assigned at birth. These patients can undergo treatment such as hormone therapy and have plastic and sexual reassignment surgeries to look more like the sex they most identify with.

These surgeries are pretty hard — core but the results are amazing: things like surgical reconstruction that inverts the penis into the body to make a vagina, or non — penile inversion techniques where the penis and testicles are amputated and plastic surgery shapes female — looking genitals. (See? Amazing.)

Surgery can also give these patients a more feminine appearance by shaving thyroid cartilage (the Adam’s apple) and embedding breast implants.

Can you go from female to male? Yes, you can. Phalloplasty or metoidioplasty can create a penis. In phalloplasty, tissue grafted from another site (an arm or leg, say) fashions a penis and extends the urethra for urination. An implant is added for penile firmness. It’s expensive surgery and has a long list of complications, but these patients are usually capable of sexual penetration with their partner.

Metoidioplasty involves testosterone therapy. Since the clitoris and penis are the same kind of tissue, hormones cause the clit to grow in size. Surgery moves the enlarged clitoris to normal penis position. An implant is not needed because a clitoris is erectile tissue and should work the same as a penis. This procedure is simpler with fewer complications than a phalloplasty, but the end result may not be as desirable. The clitoris does enlarge but is still very small (1.5 — 2”) and penetrative sex may be difficult. Female to male transgender patients may also undergo a hysterectomy to remove their uterus, fallopian tubes, and ovaries, a mastectomy to remove their breasts, and vaginoplasty to close their vagina.

The penis has so much to live up to. It’s hard, it’s soft, it urinates, it ejaculates, it rules the world! But even this powerful being fails from time to time.

Erectile dysfunction occurs when blood flow to the corpus cavernosum gets disrupted. Treatment includes injections, a penis prosthesis, and medication. Erectile assistance drugs are one of the best things that ever hit the market. But when ED commercials say, “If you have an erection lasting four hours, seek medical attention,” trust me, they ain’t lying. The condition is called priapism. Priapism occurs for all sorts of reasons, including diabetes, cardiovascular disease, and hormonal imbalance. It can also follow medication use, including ED drugs. Unfortunately the treatment for a prolonged erection is not to keep stroking it until it goes away. It requires medical attention. The patient may be given cold compresses or get a needle inserted into their penis to physically remove the blood.

In America, when a male baby is born, the hot topic of circumcision comes up. To me, circumcision is like a fashion trend — one minute it’s in, the next minute it’s out. I tend to think that if you are born with it, you need it (unless it’s diseased). Why cut off perfectly healthy foreskin? Foreskin adds width to the penis and has a function! It has lubricating properties. It also protects the penis and vagina from chaffing during sex. Foreskin also makes jerking off a hell of a lot easier, too.

One of the pro — circumcision arguments involves hygiene. Foreskin allows smegma to accumulate. Yes, smegma is an actual thing. It’s a white, cheeselike substance that forms between the penis and foreskin. It’s made of dead skin cells and oils secreted from glands in the penis skin. When it builds up, it can irritate and inflame the penis, making the skin more prone to infections, including STDs. Phimosis occurs when inflammation causes the foreskin to cover the head of the penis. Paraphimosis involves foreskin stuck behind the penile head. It becomes an emergency if stuck like that for hours, as it could actually strangle the penis.

Did you know you can break your wang? It’s called penile fracture. Think of a hard cock hitting a brick wall, or impacting a vagina at 40mph during pneumatic sex. The penis bends and one or both of the blood — filled corpus cavernosa ruptures or bursts. There’s a cracking sound and you get a large purple bruise the length of your shaft. It hurts like a bitch and you need medical help. Surgery can repair the damage. Ignoring it can lead to erectile dysfunction, urethral scarring, and a bent penis.

On the female side of things, there’s nothing so dramatic as penile fracture, but there is such thing as prolapse, a condition most commonly associated with age and childbirth. The pelvic floor muscles are strong and almost woven like a basket to hold the organs in. During childbirth, a woman vigorously pushes a large object out of her vag and the strain and pressure can damage pelvic muscles. The uterus droops into the vagina, pulling the bladder and rectum along for the ride. Extreme prolapse requires surgery.

“The penis has so much to live up to. It’s hard, it’s soft, it urinates, it ejaculates, it rules the world! But even this powerful being fails from time to time.”

Risks come with everything in life. You eat cake for breakfast, lunch, and dinner, you get fat. You drink vodka all day, you get cirrhosis. You smoke cigarettes, you get lung cancer. You have sex, you get syphilis. (Okay, to contract syphilis, you’d have to be pretty unlucky, but of course it does happen.)

In general it’s better to get a bacterial STD than a viral one because antibiotics kill bacteria. If you have a bacterial infection and take meds, it should clear up nicely and your beautiful genitals will return to normal. Antiviral drugs are a little different. These drugs can be very effective and slow down or stop the virus from replicating, but it does not eradicate the virus. It’s always hiding there. In short, there are good STDs to get, and bad ones.

Bacterial STDs include chlamydia, gonorrhea, and syphilis. They cause odors, burning, lumps, bumps, and drip on the tip. Untreated, they can cause serious problems, including pelvic inflammatory disease (which scars the fallopian tubes, leading to infertility), brain damage, and death.

Viral STDs include herpes (genital and oral), HPV (human papillomavirus), HIV, and hepatitis C. If your partner has a cold sore and wants to go down on you, run! “Cold sores” are a nice way of saying “mouth herpes.” Which can become vagina or penis herpes. Herpes spreads mouth to mouth, mouth to penis, penis to vagina, penis to anus, mouth to anus, vagina to vagina. Catch my drift?

HIV and Hepatitis C may act differently but have the same mode of entry. Though not present in saliva, they are present in semen and blood. If you are a person that likes to partake in facials, HIV/Hep C can gain entry via semen getting in your eyes, nose, or mouth. Vigorous intercourse also causes tears in both the anus and the vagina, opening up an entryway for blood to make contact with semen.

HPV causes genital warts. It can also cause abnormal cells in the uterine cervix to grow, potentially leading to cancer. HPV can also cause changes in throat cells, which can lead to throat cancer, and in the penis, which can lead to penile cancer. The best way to avoid infection and disease is by using a condom. Condoms, however, are not a 100 percent guarantee.

But let’s end on a different note. Some people, bored with the old in and out, turn to things like genital piercings, subdermal implants, cock rings, and surgical modifications (like penis and tongue splitting).

The insertion of foreign bodies is another avenue for exploration. For example, people love sticking things up their butt. This is anecdotal, but in my professional experience, every single foreign body I have ever received in pathology that came out of a rectum has been from a man.

Why? The magical prostate gland. It’s located directly beneath the bladder and can be accessed in two ways: through the skin between the penis or anus (the perineum, “taint,” or “gooch”) or direct access through the anus. When a man is aroused, the prostate enlarges and the seminal vesicles get all juicy. When it is rubbed, the super sensitive nerves can cause intense, prolonged orgasms, orgasms without penis stimulation, even multiple orgasms! Squeezing the butt cheeks (like holding in a fart) at the time of orgasm heightens the sensation. Granted, the topic of anal stimulation makes heterosexual men uncomfortable. Most men think touching or sticking something up their butt makes them gay and therefore the area is off — limits. As Ali Wong says in her stand — up, if they only knew they had a clit up their ass, they might change their mind!

Butthole pleasures are nice, but keep one thing in mind: suction. You know when you have that feeling you have to poop but you can’t go because you are in an important meeting…or at Target? If you hold it in, the feeling goes away — it gets sucked back up! And I’ve seen some impressive things sucked up into rectums, including a baseball, giant dildos/vibrators, hair spray bottles, shaving cream cans, travel toothbrush holders, and a variety of fruits and vegetables including a half — eaten pear. The pear was my favorite until I recently heard of a pathologist’s assistant who extracted lizards from someone’s rectum.

Treatment for these things is either manual or surgical removal. Not fun.

The point of all this? Protect yo self before you wreck yo self. If you do get an infection, get treatment STAT. And don’t spread that shit — it ain’t cool. If you don’t want a baby, use birth control correctly. And don’t judge! I like being choked during sex and some girls like having their feet stimulated. Whatever floats your boat.

Men, let your lady play with your ass. You can thank me later. But if you decide to stick something up your butt, be careful — it could get lost up there forever!

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