Ibn Majah

Commentary:
(1)
From this it is understood that the Noble Prophet sallallahu alayhi wa sallam used to perform the Fajr prayer at its earliest time.

(2)
Women also used to participate in the prayers along with men.
The wisdom in this is that when the Prophet sallallahu alayhi wa sallam would deliver admonitions or issues would be asked from him, women would also listen and acquire knowledge of the religion.
Sometimes, a woman herself would ask a question regarding a religious issue.
Even now, if women, while observing proper etiquette, wish to come to the mosque for prayer, they should not be prevented, although performing prayer at home is more virtuous for women than praying in the mosque.

(3)
From the clarification of the Mother of the Believers, it is understood that the reason women were not recognized was that at the time of finishing the prayer, there was not enough light to know which woman, covered in her cloak, was leaving. In greater light, even while observing hijab, a woman who is from among relatives and whom a man knows could be recognized.

(4)
Despite the recitation being lengthy in Fajr, the fact that the prayer would finish so quickly shows that the prayer would be established very soon and performed at its earliest time.

(5)
Women, after concluding the prayer with salam, would not sit for remembrance and supplications, but would immediately get up and leave, whereas the men would not stand up until all the women had left the mosque.
As is explicitly mentioned in other ahadith.