“Whether you wear a bra at night is really a comfort preference,” explains Jené Luciani Sena, bra expert and author of The Bra Book. “Some women are just more comfortable wearing them.” Wearing a bra, in general, can feel, well, unnecessary. In fact, there’s even a study that suggests wearing a bra too often can lead to sagging. However, Luciani Sena encourages you to take that short-lived study with a grain of salt. If you’re small breasted and have little breast tissue, you might be able to get away with not wearing a bra. But since the average bra size in America is 34DD, it’s in most people’s best interest to wear one during the day. Designed to fight gravity, a high-quality, well-fitting bra can prevent sagging, keep your posture intact, and make you feel more comfortable and confident. So why not bring all those perks to your bedtime routine? RELATED: How to Find the Best Bra for Your Breast Shape What you’ll definitely want to avoid sleeping in is a tight, compression sports bra or anything with underwire. When worn for extended periods of time, a compression bra can press down on your lymphatic system, which doesn’t do your boobs or your body any favors. As for underwire styles, one wrong move and you could be dealing with some major discomfort (and why sabotage your own sleep like that?). Beyond factors related to breast comfort and support, wearing any tight-fitting garment for a long time can also up the likelihood of skin irritations such as rashes, body breakouts, or fungal infection, warns John Paul Tutela, MD, a board certified plastic surgeon. All the more reason to steer clear of anything too small or too constricting. Technically, there’s no downside to wearing a looser, less restricting sports bra overnight, again, as long as it’s not super tight. Wearing the extra layer while sleeping won’t make your boobs perkier or keep them from sagging—but it also won’t stunt growth (a common misconception). The one downside, if any, would be that keeping a bra on overnight could result in physical discomfort, but there are lounge-worthy workarounds if you still prefer the added support. RELATED: Is It Bad to Wear a Sports Bra All Day, Every Day? We Asked the Experts When it comes to wearing a bra to bed, comfort is key. Luciani Sena says to look for a garment that’s more designed for relaxing and sleeping. While nursing and maternity styles used to be the gold standard of overnight bras, there’s an entire category—the beautiful world of lounge bras—designed purely with comfort in mind: simple silhouettes, minimal support, soft, breathable fabric, and no hardware. “If you pick something that’s stretchy, seamless, and all one piece, you can find something alpha-sized,” Luciani Sena says. “It’ll fit you even if it’s that time of the month.” You’re being pleasantly hugged—not trapped—so they’re the perfect match for your sleeping needs. RELATED: 9 Million Women Helped This Brand Design Its Undeniably Comfortable Bras Something that fits properly No matter what type of bra you wear overnight, Luciani Sena says it’s important to master the fit. Any bra that’s tight in the chest, ribcage, or shows some indentation marks on the shoulders shouldn’t be worn for extended periods of time—especially as you’re (hopefully) clocking in eight precious hours of sleep. To ensure you’re wearing a comfortable layer during your waking and sleeping hours, Luciani Sena recommends getting a bra fitting once a year to reassess your assets. Something squeaky clean If you’re going to sleep in a bra, there’s one big thing you have to do before climbing into bed, turning off the lights, and sailing off to dreamland: Put on a fresh bra. Wearing a dirty bra—especially one that’s covered in a day’s worth of sweat—can lead to rashes, irritation, and a fungal infection. The bra you wear to bed should be clean, and not the one you’ve been wearing all day. Do your skin a favor and slip on a clean bra before bed, then change into a fresh one when you wake up.