Sharing a bed with your partner is usually seen as a given in a relationship, especially if you and your partner live together.
Sharing your bed with someone else can impact the quality of your sleep, both positively and negatively. But it all depends on your regular sleep patterns, and those of the person you're sharing with.
So, if you're sharing a bed with someone else, consider the conditions that sharing a bed creates for you, including what time you both normally go to bed, and what you do before sleeping.