With a crippled economy forcing millions of cash-strapped Americans to entertain themselves at home, it's not surprising that one particular product is seeing a sales increase — condoms.

While car purchases plummeted and designer clothes mostly stayed on the racks, sales of condoms in the U.S. rose 5 percent in the fourth quarter of 2008, and 6 percent in January versus the same time periods the previous year, The Nielsen Co reports.

The sales bump squares solidly with one of the nation's most common trends during any recession: nesting. At the same time, condoms make for a relatively inexpensive form of birth control at a time many cash-strapped families are hesitant to grow.

"If people don't have the money to go out to a fancy dinner or are looking to cut back, Trojan gives them some real affordable ways to stay in and make some great memories together," says Jim Daniels, vice president of marketing for Trojan, the nation's biggest condom maker.

Contraception may also be more popular during a time when families are stretching dollars and want to avoid having more mouths to feed. "Obviously people in general want to avoid ... unintended pregnancies," Daniels says. "But in a down economy, those costs are even more burdensome to bear."

Pam Piligian, of Fitzgerald+CO, the ad agency for Durex condoms, says that condoms are "recession resistant."

Still, condom sales increased at a slower rate in 2008, going up 2.3 percent over the previous year compared with a 5.5 percent increase just three years ago, according to research firm Information Resources. Marketers say they are aware of the need to continue reminding consumers that condoms are an inexpensive and healthy way to have fun.

Piligian says that in a nod to the poor economy, Durex placed coupons in newspapers and is making more coupon offers on its Web site, www.trydurex.com.

Carol Carrozza, vice president of marketing for Ansell Healthcare, maker of LifeStyles Condoms, says her company may incorporate the idea of nesting into future campaigns. "We're ... trying to determine what kind of products and marketing strategies we can come out with that will help people during these recessionary times," she says.

Trojan says the message that it's good to cocoon is already part of its promotions, and it will spend more on advertising this year than last as it launches a multimedia campaign to promote two new products.

Trojan 2Go, a thin plastic case with a condom inside, hits store shelves this month while a new condom, Trojan Ecstasy, is scheduled for sale in the spring.