A question that was asked to Ash Shaykh Saalih Al-Fouzaan may Allah preserve him:
Question: Oh noble Shaykh, is it true that the Shaytaan has intercourse with the women if the man doesn't seek refuge with Allah from him?
Answer: I don't know about this, however he harms and negatively affects the child. Because in the hadeeth the Messenger sallahu 'alayhi wasallam says: So if it is decreed between them to have a child then the Shaytaan will not harm him. So the danger lies in leaving off the (Du'a) or saying the Basmalah(In the name of Allah) and that is when the Shaytaan abuses the child (when they are left off). As for him having intercourse with the women Allah knows best I donıt know.
Footnote:# Hadith of ibn ıAbbas in Sahih Bukhari(397) and Muslim(2591).