Hazrat Saeed bin Musayyib (may Allah have mercy on him) narrates that Hazrat Umar (may Allah be pleased with him) consulted Hazrat Ali (may Allah be pleased with him) bin Abi Talib (may Allah be pleased with him) and Hazrat Zaid bin Thabit (may Allah be pleased with him) regarding this matter. Hazrat Zaid (may Allah be pleased with him) said that as soon as a woman gives birth to a child, her waiting period (iddah) is completed. Hazrat Ali (may Allah be pleased with him) said that her waiting period is four months and ten days. Hazrat Zaid said that if a woman has reached such an age in which pregnancy and childbirth are not conceivable, then what will be her waiting period? Hazrat Ali (may Allah be pleased with him) said that the longer of the two periods will be the waiting period. Hazrat Umar (may Allah be pleased with him) said that if the body of the pregnant woman's husband has not yet been lowered into the grave and she gives birth to the child, then her waiting period is completed.