Stipulating a condition [about exiting ihram] in Hajj and ‘Umrah for one who is afraid that her menses may come
Question

                A woman wants to do ‘Umrah but there is the possibility that her period may come after she enters ihram and before she does tawaaf. Can she stipulate a condition [about exiting ihram] because she is afraid that she may hold her family up?.
Praise be to Allah.
    If a woman wants to do ‘Umrah but is afraid her menses may 
    come before she completes it, she may stipulate a condition [about exiting 
    ihram], then if she gets her menses she can exit ihram and will not have to 
    do anything. 

    The basic principle about it being permissible to stipulate 
    such a condition is the report narrated by al-Bukhaari (5089) and Muslim 
    (1207) from ‘Aa’ishah (may Allah be pleased with her) who said: The 
    Messenger of Allah (blessings and peace of Allah be upon him) entered upon 
    Dubaa‘ah bint az-Zubayr and said to her: “Perhaps you want to do Hajj?” She 
    said: By Allah, I am always in pain. He said to her: “Go for Hajj but 
    stipulate a condition and say: O Allaah, I will exit ihram from the point 
    where You have prevented me (from continuing, if some problem should 
    arise).” 

    If a person is afraid of illness or if a woman fears that her 
    menses may come, she may stipulate this condition. 

    Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) was 
    asked: With regard to stipulating a condition [about exiting ihram] in Hajj, 
    are there any specific cases in which the pilgrim should stipulate this 
    condition and say: “If something prevents me (from continuing), I will exit 
    ihram from the point where You have prevented me (from continuing)”? 

    He replied: Stipulating a condition in Hajj means saying, 
    when entering ihram: “If something prevents me (from continuing), I will 
    exit ihram from the point where You have prevented me (from continuing).” 

    Stipulating this condition is not prescribed unless there is 
    some fear of sickness, or if a woman fears that her menses may come, or if a 
    person is delayed and fears that he may miss Hajj. In these cases he or she 
    should stipulate this condition. If he stipulates this condition and 
    something happens that prevents him from completing the rituals, then he may 
    exit ihram and leave, and does not have to do anything. 

    But if he is not afraid (of any of these things happening), 
    the Sunnah is not to stipulate a condition; rather he should be firm in his 
    resolve, put his trust in Allah and think positively of Allah, may He be 
    glorified and exalted. 

    End quote from Liqa’ al-Baab al-Maftooh, 25/18 

    And Allah knows best.