First of all, it should be clear that Hajj is obligatory once in a lifetime. If a person has the means to offer Hajj, he should carry it out as soon as possible. One is not advised to delay offering Hajj, keeping in mind the fact that Hajj is one of the pillars of Islam. The Prophet (peace and blessings be upon him) said, “Islam is built upon five pillars: testifying that there is no true god except Allah and that Muhammad is the Messenger of Allah, performing Prayer, paying the Zakah, making the pilgrimage to the Sacred House (Hajj), and fasting the month of Ramadan.” (Reported by Al-Bukhari).
Dr. Rif`at Fawzi, former professor of Shari`ah at Cairo Univ., states: “It is permissible to delay Hajj until next year based on the opinion of the followers of the Shafi`i School of Fiqh that Hajj may be performed at any time during one’s lifetime, and there is nothing wrong if one who is obliged to perform Hajj delays it until a later date. So, a nursing mother is permitted to delay Hajj until the following year when she will be rest assured of her children’s well-being. Also, she is permitted to perform Hajj in the current year with a group of Muslim men and women if her security is guaranteed and she can find someone to take care of the children at home.”
Allah Almighty knows best.