Scholars disagree on the maximum duration of pregnancy. Ibn Juraij related from Jamilah bint Sa’d, from ‘Aishah, who said: Pregnancy is not be more than two years as the shadow of the spindle turns [i.e. it may seem brief]. This was mentioned by Al-Daraqutni. Jamilah bint Sa’d – the sister of ‘Ubaid ibn Sa’d – said, and Al-Laith ibn Sa’d related as well, that its maximum duration can be three years; Al-Shafi’i said four years. It is narrated from Malik from one of his two accounts – his more well-known one – five years. It is also narrated from him that there is no limit, even if it exceeds ten years, this being the third account of his. Al-Zuhri gives six or seven. Abu ‘Umar said: Some of the Companions made it up to seven years. Al-Shafi’i said: The maximum duration for it is four years. Those of Kufa say two years, nothing more. Muhammad ibn ‘Abd Al-Hakam says no more than one year. Dawud says nine months; he knows of no pregnancy longer than this. Abu ‘Umar said: This is an issue that has no basis other than scholarly opinion [ijtihad, independent legal reasoning], and the reponse to what was known about the matter concerning women. But Allah brings successful reconciliation of the matter.
… It is narrated as well that one day while Malik ibn Dinar was seated [in an assembly], behold a certain man came to him and said: Oh Abu Yayha! Make supplication for a certain woman who has been pregnant for four years, as she is in severe distress. Malik became angered, closed the Qur’an, then said: These people think we’re prophets! Then he recited, made supplication, and said: Oh Allah! If there is wind in this woman’s womb, expel it from her within the hour, and if there is a girl in her womb, replace it with a boy, for indeed you wipe out or affirm what you wish, and with you is Umm Al-Kitab [foundation of the Qur’an]. And Malik raised his hand, and the people raised their hands, and the messenger came to the man and said: Go and find your woman. The man left, and Malik did not put down his hand until the man had emerged from the door of the mosque, carrying on his neck a four-year-old boy with very curly hair, straight teeth, and whose secrets had not been asserted.
It is also narrated that a certain man came to ‘Umar ibn Al-Khattab and said: Oh Leader of the Believers! Indeed I was absent from my women for two years, then I returned and found her pregnant. And ‘Umar counseled with the people about stoning her. But Mu’adh ibn Jabal said: Oh Leader of the Believers! If you have reason for action against her, you have no reason for action against what is in her womb, so leave her alone until she gives birth. And the woman gave birth to a boy whose two front teeth had already come in, and the man recognized the resemblance. He said: It is my son; I swear by the Lord of the Ka’ba. And ‘Umar said: Women are unable to bear children like Mu’adh; if it were not for Mu’adh, ‘Umar would have perished.
… And Al-Dahhak said: My mother gave birth to me after having carried me in her womb for two years. She gave birth to me and my teeth had already come in. It is mentioned from Malik that he was carried in his mother’s womb for two years; some say for three years. It is said that Muhammad ibn ‘Ajlan remained in his mother’s womb for three years, then she died when he began to become greatly agitated, and her womb split open and he was forced out, and his teeth had already grown out. Hammad ibn Salama said: Indeed Harim ibn Hayyan was called “Harim” [“old man”] because he was in his mother’s womb for four years.