It's a common concern for mothers-to-be: how can something the size of a small watermelon pass through my vagina without wrecking the place? How could sex possibly feel the same? Will my partner be disappointed with the changes?

Without a doubt, life shifts drastically when you have a baby. And yes, your body changes in a multitude of ways. But when it comes to getting stretched out or becoming incontinent due to giving birth, there's one very important thing you can do to prevent and even repair problems: Kegels.

Kegels are exercises that strengthen the pelvic floor, which not only keeps you tight down there but also keeps you from peeing your pants every time you sneeze. Unfortunately, Kegels are also extremely boring to do.

You've probably heard your OB suggest Kegels as a good way to prepare for a coming baby or recover afterward, and you may have even tried to do them for a period of time. But it's hard to know if you're doing them right and it's even harder to know if you're making progress.

So many women give up on Kegels after a short amount of time. That's where technology comes in.

We now have these cool little devices called Kegel trainers. There are several different kinds on the market, but the general idea is that you stick this little computer into your vagina and it tells you whether you're doing your Kegels right, and how much progress you're making. Vaginal fitness trackers, if you will.

I tried a few of these, and here are my thoughts.

1. KegelSmart (Intimina, $99.95)

OVERALL RATING: 4.5/5 stars

KegelSmart, by Intimina, is the easiest-to-understand design that I tried. While the other two rely on a connected phone app, KegelSmart is a standalone product. You push a button on the side, stick it inside you, and squeeze when you feel it vibrate. It has an attached loop you pull to get it back out, and it lets you know how you're progressing via a flashing light on the side (indicating what level you've achieved).

The nice thing about the KegelSmart is that it's super-subtle. You could, conceivably, use it at work without anyone knowing. The loop is no more obtrusive than a tampon string, and the rest sits comfortably inside you. Aside from the glazed-over look of concentration on your face, nothing would seem out of the ordinary to standers-by.

I liked the feedback KegelSmart gave me, but it bored me almost as quickly as regular Kegels. I could see how some people would prefer this lower-tech option, but it found its way to the back of the drawer pretty quickly for me.

Photo: intimina

2. KGoal ($149, Minna Life)

RATING: 5/5 stars

Of the three I tried, KGoal is my favorite. Minna Life's Kegel trainer is super-comfortable. The part you insert actually inflates for the perfect fit, and it has a little arm that wraps up the front, over the labia. KGoal buzzes much like the KegelSmart, but it vibrates inside of you as well as in the arm, which happens to land squarely on a rather sensitive spot.

Yep, immediate gratification when you do your Kegels with KGoal. It also connects to an app which gives you real-time feedback. As you squeeze, a line moves on your screen, and each level feels more like a game than a workout. It's fun, it feels good, and I actually made progress. Woo!

Photo: Minna Life

3. Elvie ($199, Elvie.com)

RATING: 4/5 stars

I have to admit, Elvie is just cool. Instead of just measuring the pressure of your squeezes, Elvie actually uses multiple sensors to monitor your muscles, so there's no fooling her. Elvie offers an app similar to the KGoal, but Elvie's seems a bit more intuitive, offering different training "tracks" depending on your starting pelvic floor fitness.

It comes in a really cool case that doubles as a charger. I appreciated that the case's design is very subtle. Your kids probably won't fish it out of the drawer and pretend it's a telephone ... not that I'd know anything about that. For me, the downside is the fit.

Elvie comes with an additional cover to personalize the size, but neither size worked well for me. It kept sliding further into my vagina with every squeeze until it wasn't reading my contractions well and the arm in front settled into what felt like a horrible front-wedgie. That being said, no two vaginas are the same and my experience as far as the fit may very well be unique.

Photo: Elvie.com

Yeah, these are a little pricey. But think of all the money you'll save when you're not having to buy Depends in bulk later in life.

I use these off and on, and I do see some progress in the app, but no major changes elsewhere in my life. However, after two kids I'm not a gaping cavern down there, and I only pee when I intend to, so maybe the little bit I do is making a difference.