From Sahih Bukhari (Hadith 5165):
Narrated Ibn `Abbas:The Prophet (ﷺ) said, "If anyone of you, when having sexual intercourse with his wife, says: Bismillah, Allahumma jannibni-Sh-Shaitan wa jannib-ish-Shaitan ma razaqtana, and if it is destined that they should have a child, then Satan will never be able to harm him
Reference: Bukhari 5165