Language:
كتاب الصلاة
8
Prayers (Salat)
(108)
Chapter: Is it permissible to touch or push one's wife in prostration in order to prostrate properly?
(108)
باب هَلْ يَغْمِزُ الرَّجُلُ امْرَأَتَهُ عِنْدَ السُّجُودِ لِكَىْ يَسْجُدَ

Narrated `Aisha:

It is not good that you people have made us (women) equal to dogs and donkeys. No doubt I saw Allah's Messenger (ﷺ) praying while I used to lie between him and the Qibla and when he wanted to prostrate, he pushed my legs and I withdrew them.

حَدَّثَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا عُبَيْدُ اللَّهِ، قَالَ حَدَّثَنَا الْقَاسِمُ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ بِئْسَمَا عَدَلْتُمُونَا بِالْكَلْبِ وَالْحِمَارِ، لَقَدْ رَأَيْتُنِي وَرَسُولُ اللَّهِ صلى الله عليه وسلم يُصَلِّي، وَأَنَا مُضْطَجِعَةٌ بَيْنَهُ وَبَيْنَ الْقِبْلَةِ، فَإِذَا أَرَادَ أَنْ يَسْجُدَ غَمَزَ رِجْلَىَّ فَقَبَضْتُهُمَا‏.‏
Reference : Sahih al-Bukhari 519
In-book reference : Book 8, Hadith 166
USC-MSA web (English) reference : Vol. 1, Book 9, Hadith 498
  (deprecated numbering scheme)