Why does my period blood smell, as a gynecologist, I have been answering similar questions like this every day, especially young female patients. Menstrual blood itself actually has no smell, but when it mixes with other bacteria in our body then period blood can start to smell quite noticeably. This doesn’t always mean there are bad bacteria present or it’s anything to worry about, but sometimes it can be a sign of something bigger. It does just naturally happen from time to time though, and everyone is likely to notice this on occasion. It’s important to just stay clean and pay attention to your body. Most likely you’re the only person that can even smell it because you’re thinking about it and worried someone else might notice.