It’s in so many romance novels. Mine included. But what is that sexy groove that runs from the hips across the pelvis, disappearing beneath the waistband and directing so many eyes to the groin?

I’m going to dive into the anatomy… and end up talking about embryonic development and hernias. So if you’d rather not take an in-depth look “behind the scenes”, take another moment or two to gaze at the photo, appreciate the surface appeal, then move on with your day 🙂

But maybe you just have to know…

That groove? That’s where his inguinal ligament runs.  

It’s not a muscle, but the crease does become more prominent and well-defined when the lower abdominal muscles are toned, hip flexors are strong, and body fat is low.

The inguinal ligament runs from the anterior superior iliac spine (the crest of your front hip) to the pubic tubercle. I’ve drawn it onto the male pelvis for you. It’s connective tissue (an aponeurosis) that forms part of the anterior (front) abdominal wall.

And this is where I ruin all the fun.

That package the V is drawing your eyes to? Developmentally, the testes didn’t start out there. 

In the undifferentiated embryo, ovaries and testes both originate from the same clump of gonadal tissue. Ovaries* are more or less going to stay put, but the testes have a trip to take. They can’t stay inside the abdominal cavity as sperm need a lower temperature to develop and function.**

So the testes pack up and leave the abdominal cavity. They push through a membrane that surrounds the abdomen called the peritoneum and slide into the inguinal canal via the deep inguinal ring. As they move toward the scrotum, the spermatic cord trails behind them (containing the vas deferens along with associated blood vessels and nerves). The testes then exit the inguinal canal via the superficial inguinal ring to drop into the scrotal sac.

If you have a willing male partner (informed consent is a must!), you can locate this superficial inguinal ring near the spermatic cord’s exit point by tracing the ligament’s path downward, then hooking your finger against the opening (probe gently!)

When sperm exit the testes, they travel back along this inguinal canal, upward and into the abdomen, traveling around the bladder as they course past/through various glands to, at last, reach the urethra. 

Still with me?

So, about inguinal hernias. Yeah, it’s cringe time.

Inguinal hernias happen when a portion of the visceral peritoneum or small intestine bulges from the abdominal cavity into and/or through the inguinal canal. There are two ways this can happen. 

A direct hernia occurs when the bulge passes through a weakness in the connective tissue (posterior fascia) to enter the inguinal canal. Such a hernia is usually related to increasing age (>50 years). 

An indirect hernia develops when the bulge passes through the deep inguinal ring and into the inguinal canal. At younger ages (20s and 30s), this is most likely to be the scenario.

Bulges/hernias of both kinds can then move along the inguinal canal to varying degrees, going so far as to exit the superficial inguinal ring and bulge into the testes. Coughing, straining and other activities (e.g. exercise) can cause the protrusion to grow. Lying down will often relieve these symptoms as well as reduce the bulge.

I can’t imagine that feels any better than it sounds. 

Do you need to surgically treat inguinal hernias? That’s something to be determined by a physician. But it’s certainly not something to ignore. If enough tissue/intestine passes through the canal, “strangulation” can occur, a situation whereby the blood supply is cut off resulting in tissue death. That’s serious business. If not addressed, strangulation can and does result in death.

So that inguinal groove many of us were admiring in that first image? It has everything to do with sex. Your dropping gaze traces the path once taken by two-thirds of the package you’re admiring.

Hey, eyes up here!

*While women also have an inguinal ligament, the associated canal is much, much smaller. The round ligament that supports the uterus does pass through it. However, women are less likely to develop an inguinal hernia as the internal inguinal ring normally closes.

**As a side note, cryptorchidism is a condition where testes do not descend, at all or in part. This is usually addressed surgically to ensure fertility. Additionally, undescended testes carry a much higher risk of developing cancer.

About Anne

Though USA TODAY bestselling author Anne Renwick holds a Ph.D. in biology and greatly enjoyed tormenting the overburdened undergraduates who were her students, fiction has always been her first love. Today, she writes steampunk romance, placing a new kind of biotech in the hands of mad scientists, proper young ladies and determined villains.

Anne brings an unusual perspective to steampunk. A number of years spent locked inside the bowels of a biological research facility left her permanently altered. In her steampunk world, the Victorian fascination with all things anatomical led to a number of alarming biotechnological advances. Ones that the enemies of Britain would dearly love to possess.

To chat with Anne, stop by on Facebook or join the Department of Cryptobiology Facebook group. You can also join her newsletter list to have cover reveals, sneak peaks, sales and giveaways delivered straight to your inbox.