Musnad Ahmad 962:83

Yazid ibn Harun narrated to us, Sharik narrated to us, from Mansur, from Salim ibn Abi al-Ja'd, from Abu Umamah, who said: A woman came to the Prophet, may Allah bless him and grant him peace, and with her was a young boy she was carrying, and in her hand was another, and I do not know him to say anything except that he said: "And she was pregnant." She did not ask the Messenger of Allah, may Allah bless him and grant him peace, for anything that day except that he gave it to her. Then he said: "They are the pregnant, the child-bearing, the merciful to their children. Were it not for what they do to their husbands, the praying ones among them would enter Paradise."