Umar consulted the people regarding a woman who miscarries due to being struck.Mughira bin Shuba said, "I witnessed the Messenger of Allah ﷺ rule in such a case that compensation of a male or female slave be paid."Umar said, "Bring me someone who can testify along with you."So he brought Muhammad bin Maslama to him. Harun added in his version that he then testified along with him, meaning regarding a man striking his wife's belly.
حدثنا عثمان بن أبي شيبة وهارون بن عباد الأزدي المعنى قالا حدثنا وكيع عن هشام عن عروة
أن عمر استشار الناس في إملاص المرأة فقال المغيرة بن شعبة شهدت رسول الله ﷺ قضى فيها بغرة عبد أو أمة فقال ائتني بمن يشهد معك فأتاه بمحمد بن مسلمة زاد هارون فشهد له يعني ضرب الرجل بطن امرأته
[Sahih] Narrated by Muslim, Al-Qasamah, chapter on the blood money for a fetus, etc., no. 1683, from the hadith of Waki narrated in the same manner, but he did not mention what Harun bin Abbad Al-Azdi, the teacher of Abu Dawud, added, and Abu Dawud only transmits from someone he considers reliable.