All jurisprudence agree that the blood which a woman sees after the age of 60 years[1] is not classified as Hayd, though it might bear the signs of menstrual blood.  Likewise, if blood is discharged before completion of 50 lunar years,[2] it is treated as Hayd even if it does not bear the characteristics or signs of menstrual blood.
 
As for the blood which women see after completion of 50 lunar years until 60, the rules are as follows:
 
1. Sayyida women reach menopause [Ya’isa][3] after completion of 50 lunar years.  That is to say, she does not see Hayd blood.  As for those women who are not Sayyida, they reach menopause after completion of 50 lunar years.  This is the verdict of Imam Khomeini, Grand Ayatollah Araki, Gulpaigani and Fazel Lankarani (may Allah bless their souls).
 
2. Women who are not Sayyida reach menopause after completion of fifty lunar years and women who are Sayyida reach menopause after the age of 50 until completion of 60 lunar years.  However, if Sayyida women see blood with the signs of menses or on the days of their regular menstrual habit, they should, as an obligatory precaution, combine the 'dos' of mustahadah and 'don'ts' of haaed.  This is the verdict of grand Ayatollah Khoei (may Allah bless his soul).
 
3. The blood seen by [Sayyida or non-Sayyida] women after the age of 60 years is not classified as Hayd.   Per recommended precaution, women who are not from the clan of Quraish, if they see blood between the age of 50 and 60 years, having the same signs as those of Hayd, they should combine the 'dos' of mustahadah and 'don'ts' of haaed.  This is the verdict of Grand Ayatollah Sistani.
 
4. The Sayyeda and non-Sayyeda women reach menopause after the age of 50 years.  That is to say, if blood is discharged from them, it is not treated as Hayd, except for the women from the clan of Quraish who reach menopause after the age of 60 years.  This is the view of Grand Ayatollah Makarem Shirazi.[4]   The difference between Quraishi and non-Quraishi women in this issue is perhaps, the physical strength and ability of the former from other women.  The metabolism of their body is different from that of other women as is the case with different tribes and races that are different in terms of color, physical features, and physical power.  For example, women who live in Siberia, their age of adulthood (puberty) is different from those Arab and African women who live in a temperature that reaches 50 centigrade.  Apart from these, the position is the same even today with womens age of menopause increasing.  Many women do not reach menopause at the age of 50.  As some experts have announced, it is because of improved hygiene, nutritious and healthy food which has led to an increase in the age of menopause.[5] [6]  As we have already mentioned, 50 lunar years of age is equal to 40 eight solar years and one hundred and seventy nine days.  Given the supposition made in the questions, the same rules concerning menstruating woman is applied for you at the age of 49 years old of age.  This means, you have to act as a mustahadah.[7]
 
The following are some rules concerning mustahadah:
 
1. Those things which are haram for a mustahadah
2. Those things which are obligatory on a mustahadah
3. Those things which the Istihadah void them
4. Those things which Istihadah has no effect on
 
Those things which are haram for a menstruating woman:
 
1. It is not permissible for a medium and abundant mustahadah to enter masque and stay there, according to some scholars like Ayatollah Araki, Golpayegani and Fazel Lankarani.  According to Ayatollah Makarem and Sistani, performing ghusl for an abundant mustahadah is obligatory, but making wudu is sufficient for a medium mustahadah (those actions which making wudu is required for doing them).  According to Ayatollah Khoei and Imam Khomeini, the woman, according to the mustahabb (recommended) precaution, shouldn’t enter mosque and stay there.
2. Is it permissible for an abundant and medium Mustahadah to perform ghusl before reciting those surahs containing Sajdah?  The same previous mentioned rules are applied here.
3. According to some scholars like grand Ayatollah Golpayegani, although a mustahadah, according to the obligatory precaution, has made wudu, but she mustn’t touch the written words of the Holy Qur'an.  Ayatollah Makarem has said, “It is impermissible for a mustahadah to touch the written words of the Holy Qur'an at other times of prayers.”  Other scholars have said, they can touch it if they have already performed ghusl and wudu, however according to the mustahabb precaution, they don’t have to touch the written words of the Holy Qur'an at all.
4. It is impermissible for a mustahadah to have intercourse before performing ghusl.  She can do it after ghusl.  The ghusl she has performed for prayer is sufficient if the intercourse has done at the time of prayer, otherwise if she had intercourse before prayer time she is supposed to perform another ghusl.[8]
 
Second:  Those thing which are obligatory on a Mustahadah:
 
1. Examination: a mustahadah must examine herself before offering each prayer in order to make sure which type of istihadah she is, according to the obligatory precaution.[9]
2. Cleaning herself and changing or cleaning the pad before offering each prayer: a musthadah must change the pad before offering each prayer, according to most of scholars.  If blood has reached the outside of the farj she must purify it with water, according to all scholars.  According to Ayatollah Sistani and Makaram Shirazi, there is no need to change the pad.[10]
3. Making wudu to offer prayer or to do anything which is required wudu: A mustahadah must make wudu for each prayer in case she sees blood and also for doing anything which making wudu is required.[11]
4. Performing ghusl for medium and abundant Istihadah: it is obligatory on a medium Istihadah to perform a ghusl every day before morning prayer and before the first prayer she saw blood[12].  As for the abundant Istihadah, it is obligatory on her to perform ghusl before each prayer, but if she wants to offer her Zuhr and Asr prayers or Maghrib and Isha prayer together it would be sufficient for her to perform one ghusl for each both prayers.[13]
5. Preventing from bleeding: a menstruating woman must prevent from discharging blood before making wudu and ghusl and after the both and when she wants to offer prayer and on the day she is fasting, in case it doesn’t harm her.[14] [15]
6. When performing wudu and ghusl has been done she must offer her prayers immediately: a menstruating woman must offer her prayers immediately after she has performed wudu and ghusl if she guesses that would see blood during prayers of before offering prayers.  Note: this issue has no contradiction with saying adhan and iqamah, reciting mustahabb duas and doing the recommended acts of prayers.  Therefore, if she has performed wudu and ghusl but didn’t offer her prayer immediately her prayers are void, unless she makes sure the blood has stopped from discharging during prayer. [16]
7. Delaying offering prayers until she may become tahir: if a mustahadah has performed wudu and ghusl and after that the blood apparently stopped from discharging and she knows that if she delays offering her prayers, as long as she can perform wudu and ghusl and offer prayers, she will become completely pure then she must delay it and offer her prayers after performing wudu and ghusl.[17]
8. Final ghusl: an abundant mustahadah must perform ghusl when she becomes completely pure.  If she knows that after performing ghusl didn’t see any blood there would be no need to do another ghusl.  As per the medium Istihadah, the same rules concerning abundant mustahadah is applied here, according to all scholars, however according to Ayatollah Makarem, the same rule concerning qalilah (minor) mustahadah is applied for the medium.  Ayatollah Sistani has said, “As per the medium mustahadah, she doesn’t need to perform ghusl after she becomes tahir.”[18]
 
Third:  Things that Istihadah void them:
 
1. The menstrual blood void wudu.  This means it is one of the thing that void wudu.[19]
2. If a mustahadah doesn’t prevent from discharging blood, as she is supposed to do, and the blood has discharged, she must perform her wudu and ghusl and offer her prayers again.[20]
3. What is the ruing of fasting on a menstruating woman who neglected performing her ghusls?
According to some scholars like Ayatollah Sistani, her fast is absolutely valid, however she is supposed to compensate her fast, according to the mustahabb precaution.  According to other scholars like Imam Khomeini, Ayatollah Khoei, Fazel and Makarem, the daily ghusl is required and, according to the obligatory precaution, she must perform ghusl the night before fasting, however doing ghusl for the next night is not necessary.[21]
 
Fourth:  Things that Istihadah has no effect on:
 
1. According to most of scholars, it is permissible for a mustahadah to offer her Qada prayers.  If she wants to do so she must follow the same rules concerning Ada prayers.  According to the mustahabb precaution, she is not supposed to offer her Qada prayers while she is mustahadah.  According to others, she can offer her Qada prayers just in case she dreads to die if she doesn’t offer it.[22]
2. Offering Salat al-Ayãt (prayers for eclipse or frightening acts of God) is obligatory on a mustahadah.  The same rules concerning daily prayers are applied here.  She can’t offer both prayers with one ghusl, though the 'ayat' has been coincided with daily prayers.
3. Divorcing mustahadah is valid and there is no need to perform ghusl in order to do so.[23] [24]

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