It is reported supposedly from Ja'far as-Sadiq and Imam 'Ali (as) that Imam Hasan divorced a lot, and had up to 90 wives. (Suyuti) [This report has no isnāds]
Abu Talib Makki (d. 386 AH/996 AD), author of Qut al-Qulub, repeated the allegation that Imam Hasan (as) divorced a lot.
‘After a thorough study of these reports, I have found that the first man known to accuse Imam Hasan of "marrying and divorcing" was the 2nd Abbasid Khalifa, Mansur, who because of his dynastic policies was bent upon belittling Amir al-Mu'minin `Ali and his descendants. […] For this purpose, he gave a public address after that mass arrest, in which he shamelessly said: "By God, we left the descendants of Abu Talib and the Khilafat; we did not interfere at all. `Ali ibn Abi Talib became Khalifa. After him Hasan ibn `Ali became Khalifa. By God, he did not deserve it. He was offered money, which he accepted; Mu'awiya sent him a message that he would make him his successor. So, Hasan abdicated the Khilafat and left the government and power. He left everything to Mu'awiya, and turned his attention, to women, marrying one woman today, divorcing another one tomorrow. He remained like this till he died in his bed."
(AI-Mas'udi; in Muruj al-Dhahab, Vol.3, p.226).’ (Sayyed Saeed Akhtar Rizvi, Imam Hasan 'The Myth of his Divorces', Al-Serat, Vol 4 (1978), No 3).
He actually only had three wives, the last of which poisoned him, at the request of Yazid ibn Mu’awiya (See Suyuti again)