A few months ago, I was planning Sara's birthday weekend in New York City and consulted with her about which hotel would serve as home base. As Sara and I sorted through a half-dozen websites, looking at pictures and reading reviews, she noted which hotels were close to the theater district and the room rates. My reply? "Marty from London said the king-size beds at the Westin Times Square were huge." We booked it.

A week later, while arranging our family trip to Miami for February break, it happened again. "This place is great," Sara decided. "They have a kiddie pool for Teddy, and a playground, and arts-and-crafts activities for Hazel . . ."

"And the suites have Jacuzzi tubs in the master bedrooms!" I interjected. Again, a reservation was made within minutes.

Many people will tell you that a hotel room is just a place to sleep while on a trip, but I beg to differ. That's because I'm a big believer in the virtues of "hotel sex," and while I can't put my finger on exactly why, I know it's a phenomenon that exists for many, if not most, couples. I've talked to friends and relatives who agree with the idea that regardless of why you're in a hotel for a night, whether it's business or pleasure, visiting family or getting away for an anniversary, the chances of a married couple making love goes up exponentially when there's a mint on the pillow.

So why is check-in a turn-on? Do hotel chains put pheromones in their air-conditioning units? Is there something in the newness of the location, giving couples a risk-free opportunity to "take their act on the road"? Or is it as simple as the fact that hotels are places where someone else will replenish the linens and even deliver overpriced club sandwiches to your door, creating an atmosphere of freedom that encourages friskiness?

The first time Sara and I ever stayed in a hotel together was toward the end of college, when an older friend from Brandeis got married in New Jersey. We drove down and arrived at an offramp-adjacent Sheraton, knowing that between the ceremony, reception, and our need to drive home first thing in the morning, we might spend less than an hour in the hotel awake. But I remember checking into the hotel, opening the door of our "deluxe" room with a view of the Garden State Parkway, and feeling like carrying Sara over the threshold. It was our honeymoon suite, even though we weren't the ones getting hitched. It also set a precedent that would be upheld for more than 16 years and counting.

In that time, I've tried to figure out what's behind the "hotel sex" mind-set. When possible to do so without incurring dirty looks or harassment suits, I've talked to other couples to see if it was a cultural thing or age specific, but it seems nearly universal. My buddy Matt had a hypothesis that since many couples meet at a time when they are living with roommates or, worse, their families, hotel rooms, with their steel doors and deadbolts, offer a level of privacy they can get nowhere else. After all, there's no such thing as a "Do not disturb" sign when you're cohabitating with a bunch of roomies who are privy to every creak of your bedsprings.

The seclusion theory certainly holds water when one realizes there is a real difference between "hotel sex" and "bed-and-breakfast sex," which requires more restraint and subtlety. That's because at a B&B, there's a good chance you'll end up sharing a breakfast table with your neighbors the next morning.

Maybe time will change our "hotel sex" drive. It could be that in 15 years, when Sara and I fly off to see Hazel graduate from college, or in 25 years when we take a trip to watch Teddy help the Patriots win their 14th Super Bowl, we'll check into a hotel, put our bags down, take a nap, and that's as far as things will go. But for now, and the foreseeable future, I'll treat every check-in as an opportunity for some suite lovin' . . . with no reservations.

Shawn Peters writes about sports, domesticity, and more at shawnpeters.net. Send comments to coupling@globe.com.

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