Assalamu Alaikum
If the woman is not pregnant and she menstruates (is of child-bearing age), then her ‘iddah is three complete menstrual cycles after the divorce, i.e., her period comes then she becomes pure, then her period comes again and she becomes pure, then her period comes again and she becomes pure. That is three complete menstrual cycles, regardless of whether the time between them is long or short. Based on this, if he divorces her and she is breastfeeding and does not menstruate until two years later, then she remains in ‘iddah until she has had three menstrual cycles, so she may stay in this state for two years or more. The point is that she should go through three complete menstrual cycles whether the time involved is long or short, because Allaah says (interpretation of the meaning):
“And divorced women shall wait (as regards their marriage) for three menstrual periods”
[al-Baqarah 2:228]
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