What is the expiation for adultery and abortion after two pregnancies and two miscarriages before less than forty days, along with repentance and proposing to the fiancée?

Committing adultery is a grave sin. One must frequently seek forgiveness (Istighfar), engage in remembrance (Dhikr), perform expiatory good deeds, and weep in regret over the sin. There are signs for the acceptance of repentance, and an abortion performed before forty days has no expiation other than repentance. It is not permissible for an adulterer to marry the woman with whom he committed adultery unless she has repented and her womb has been cleared by one menstrual period if she is not pregnant, or by giving birth if she is pregnant.