The Prophet ﷺ said, "If any of you, when he intends to approach his wife, says, 'In the name of Allah. O Allah, keep Satan away from us and keep Satan away from what You have provided for us,' and a child is destined to be born to them from that union, no devil will ever harm that child."
حدثنا محمد بن عيسى حدثنا جرير عن منصور عن سالم بن أبي الجعد عن كريب
قال النبي ﷺ لو أن أحدكم إذا أراد أن يأتي أهله قال بسم الله اللهم جنبنا الشيطان وجنب الشيطان ما رزقتنا ثم قدر أن يكون بينهما ولد في ذلك لم يضره شيطان أبدا
Reported by Muslim, Marriage, chapter on what should be said at intercourse, no. 1434, from the hadith of Jareer, and Bukhari, Marriage, chapter on what a man says when he comes to his wife, no. 5165, from the hadith of Mansur, similarly.