What is the ruling on a husband divorcing his wife three separate times during her pregnancies, and does divorce during pregnancy count, and what is its expiation?

If the anger was so severe that you lost consciousness of what you were saying, then nothing is incumbent upon you. However, if you were conscious, then your divorce is effective. Your intention behind repeating the word of divorce will be considered: if you intended emphasis or had no intention at all, then it counts as one divorce. But if you intended to initiate divorce with all three pronouncements, then you are bound by three. The last two pronouncements do not take effect if your wife has become irrevocably divorced from you by the first pronouncement. As for divorce during pregnancy, it is effective by the consensus of the jurists. It is advisable to consult a Sharia (definition) court to examine the details of the matter.