Narrated Ibn `Abbas:
The Prophet (ﷺ) said, "If anyone of you, when intending to have a sexual intercourse with his wife, says:
'Bismillah, Allahumma jannibna-sh-shaitan, wa jannibi-sh-shaitan ma razaqtana,'
and if the couple are destined to have a child (out of that very sexual relation), then Satan will never be able to harm that child."
https://sunnah.com/bukhari:6388
Reference : Sahih al-Bukhari 6388 In-book reference : Book 80, Hadith 83