Is a waiting period (iddah) incumbent upon a woman who has been separated from her husband due to suckling (rada'ah)? And if not, what is the wisdom behind that, given that the wisdom of the waiting period is to ascertain the emptiness of the womb?

A woman with whom consummation has occurred and who has been separated from her husband due to prohibitive suckling must observe the 'iddah (waiting period). Most scholars hold that her 'iddah is the same as that of a divorced woman. Every separation between spouses necessitates an 'iddah similar to that of divorce, whether it is due to khul' (divorce at the wife's instance), li'an (oath of condemnation), suckling, annulment due to a defect, destitution, manumission, difference in religion, or other reasons, according to the majority of scholars.