Your p.m. pose can affect a lot more than just your slumber.

Your sleeping pose can have a major impact on your slumber—as well as your overall health. Poor p.m. posture could potentially cause back and neck pain, fatigue, sleep apnea, muscle cramping, impaired circulation, headaches, heartburn, tummy troubles, and even premature wrinkles.

Wondering which sleep spot is best? Check out the rankings, below, from best to worst.

1. On Your Back

Though it’s not the most popular position—only eight percent of people sleep on their backs—it’s still the best. By far the healthiest option for most people, sleeping on your back allows your head, neck, and spine to rest in a neutral position. This means that there’s no extra pressure on those areas, so you're less likely to experience pain. Sleeping facing the ceiling also ideal for warding off acid reflux. Just be sure to use a pillow that elevates and supports your head enough—you want your stomach to be below your esophagus to prevent food or acid from coming up your digestive tract. However, snoozing on your back can cause the tongue to block the breathing tube, making it a dangerous position for those who suffer from sleep apnea (a condition that causes periods of breathlessness). This position can also make snoring more severe.

2. On Your Side

This position (where your torso and legs are relatively straight) also helps decrease acid reflux, and since your spine is elongated, it wards off back and neck pain. Plus, you're less likely to snore in this snooze posture, because it keeps airways open. For that reason, it’s also the best choice for those with sleep apnea. Fifteen percent of adult choose to sleep on their side, but there’s one downside: It can lead to wrinkles, because half of your face pushes against a pillow.

3. In the Fetal Position

With 41 percent of adults choosing this option, it’s the most popular sleep position. A loose, fetal position (where you're on your side and your torso is hunched and your knees are bent)—especially on your left side—is great if you're pregnant. That's because it improves circulation in your body and in the fetus, and it prevents your uterus from pressing against your liver, which is on your right side. This pose is also good for snorers. But resting in a fetal position that's curled up too tightly can restrict breathing in your diaphragm. And it can leave you feeling a bit sore in the morning, particularly if you have arthritis in your joints or back. Prevent these woes by straightening out your body as much as you can, instead of tucking your chin into your chest and pulling your knees up high. You can also reduce strain on your hips by placing a pillow between your knees.

4. On Your Stomach

While this is good for easing snoring, it’s bad for practically everything else. Seven percent of adults pick this pose, but it can lead to back and neck pain, since it’s hard to keep your spine in a neutral position. Plus, stomach sleepers put pressure on their muscles and joints, possibly leading to numbness, tingling, aches, and irritated nerves. It’s best to try to choose another position, but if you must sleep on your stomach, try lying facedown to keep upper airways open—instead of with your head turned to one side—with your forehead propped up on a pillow to allow room to breathe.