What is the expiation for aborting a fetus at 40 days old due to poor financial circumstances?

Aborting a fetus is, according to the preponderant opinion, forbidden unless there is a legitimate Sharia-compliant excuse. Poor financial conditions are not a legitimate excuse, for Allah is the Provider. If the abortion occurred before forty days, the wife must repent and seek forgiveness. If it occurred after forty days, she is also liable for the blood money (diyya), which is a ghurrah (a male or female slave), and is currently estimated at one-tenth of the mother's blood money. It is to be handed over to the fetus's heirs unless they waive it, and the mother inherits nothing from it. The husband must also repent and seek forgiveness because he permitted it and assisted in it.