Musnad Ahmad Hadith 22702

It is narrated from Ubadah (may Allah be pleased with him) that once I was ill, the Noble Prophet (ﷺ) came to visit me along with some Ansari people. He asked the people present there, "Do you know who is a martyr (shaheed)?" The people remained silent. The Noble Prophet (ﷺ) asked again, and the people remained silent again. The Noble Prophet (ﷺ) asked the same question a third time, so I said to my wife, "Support me and make me sit up." She did so, and I submitted, "The person who accepts Islam, migrates, and then is martyred in the path of Allah, he is a martyr." The Noble Prophet (ﷺ) said, "In that case, the martyrs of my Ummah will be very few. Being killed in the path of Allah is also martyrdom, dying from a stomach illness is also martyrdom, drowning and dying is also martyrdom, and a woman dying in the state of childbirth is also martyrdom."