Islamic Fiqh > Marriage and family > Iddah (the waiting period) > The iddah according to whether the qur' means menstruation or purity, and the menstruation of the divorce
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Updated on 25 September 2026 at 3:23 PM
This part belongs to the full section: All sections of this part.
On the view that the qur' is the menstruation, the view of the Hanafis and the Hanbalis, the husband retains the right to take his wife back until she washes from her third menstruation; when she washes, the revocation ceases, for washing grants her a ruling of the pure, the lawfulness of prayer. On the view that the qur' is the purity, the view of the Malikis and the Shafi'is and one narration of the Hanbalis, the iddah ends as soon as she enters the blood of the third menstruation and remarriage becomes lawful for her, as detailed in the previous question.
Does the menstruation during which the divorce takes place count in the iddah? The scholars agreed: if the woman is divorced during her menses, that menstruation does not count in her iddah. Imam Ibn Qudamah said: the menstruation of the divorce does not count in her iddah, without disagreement among the scholars; Allah ordained three complete quru', and the one of the divorce cannot be completed together with two others; moreover, divorce was forbidden during menses only to avoid lengthening the iddah, whereas counting it would shorten it, which would not make divorce a forbidden act. Whoever says "the quru' are the purities" counts for her the purity of the divorce, even if only a moment of it remained. All the holders of that view, except al-Zuhri alone, hold that she counts three quru' besides the purity of the divorce; it is related from Abu Ubayd that if the husband consummated the marriage in that purity, the remainder does not count, for it is a time in which divorce was forbidden, like the time of menses.
Ibn Qudamah answers: divorce was forbidden during menses to avert the harm of lengthening the iddah; if the remainder of the purity did not count, divorce in purity would harm the woman and lengthen it. What is related from Abu Ubayd is not sound, for the prohibition of divorce during menses rests precisely on the fact that she does not count its remainder; one cannot therefore make that prohibition the cause of the non-counting, the cause becoming the effect. If the woman is divorced in purity, the prohibition bears rather on the doubt and the fear of regret upon the appearance of signs of pregnancy. Then: if the letters of the divorce end with the purity, the divorce falls at the beginning of the menstruation, which is forbidden, and that menstruation does not count: she owes three menstruations, or three purities according to the second narration. And if the man says "you are divorced at the end of your purity" or "at the end of a part of your purity," and the letters of the formula end leaving only the moment of intercourse, that purity does not count, for the iddah exists only after the divorce, and neither what precedes it nor what approaches it may be counted (al-Mughni).
When the woman accustomed to menstruating sees her menses stop, the case divides according to whether she has already menstruated once or twice since the divorce, and according to whether the cause of the stoppage is known or unknown.
First case: she has menstruated once or twice, then her menses stopped
The jurists differed over the divorced woman who menstruates once or twice and then sees her menses stop: does she wait for the menstruation however long the span may be? Does she enter the age of menopause? Or does she remain nine months, the duration of pregnancy, then three months? The Hanafis, the Shafi'is in the school, as well as Ashhab and Ibn al-Arabi among the Malikis, hold that she remains one of the women with quru': her iddah ends, in divorce as in the other cases of separation, only with three menstruations, however long they may be, or by entering the age of menopause, the age at which women like her no longer menstruate, and then she counts three months like the woman who has despaired. If her habit in her youth was one menstruation a year, she is not in doubt of menopause and can be certain she belongs to the women who menstruate; the long interval between two menstruations does not remove her from this category, and whoever imposed the months iddah on her would contradict the Book, Allah having made no distinction between a long and a short habit (Bada'i al-Sana'i 3/195; Ahkam al-Quran 5/352-353; al-Jawharah al-nirah 5/16; Ikhtilaf al-'ulama' of al-Marwazi, p. 170; Ahkam al-Quran of Ibn al-Arabi 4/285).
It is related, through al-A'mash and Mansur, from Ibrahim, from Alqamah ibn Qays, that a man divorced his wife once or twice; she menstruated once or twice, then her menses stopped for seventeen or eighteen months, and then she died. He came to ask Ibn Mas'ud, who said: "May Allah withhold her inheritance from you: it is you who inherit from her" (reported by al-Bayhaqi in as-Sunan al-Kubra, 7/419).
The Malikis in the school, the Hanbalis and the Shafi'is in one view hold that the woman who menstruated once or twice and then sees her menses stop without knowing the cause sees her iddah end only after a year from the stoppage: nine months of waiting, the most frequent duration of pregnancy, to establish that she is not pregnant, then three months of iddah. Ibn Qudamah relates that al-Shafi'i said: "This is the judgment Umar pronounced between the Muhajirun and the Ansar; whoever knew it did not deny it, and so it became a consensus."
If she menstruates before the year is complete, even for a moment, she returns to the quru', which are the original rule, like the man with an incapacity who prays with tayammum and then sees water. If the menses return after the year and she has married, she does not return to the quru', for her iddah has been judged complete and her marriage valid, like the young girl who menstruates after her iddah and her marriage. Imam Malik relates in al-Muwatta, from Yahya ibn Sa'id and from Yazid ibn Abd Allah ibn Qusayt al-Laythi, from Sa'id ibn al-Musayyib, that Umar ibn al-Khattab said: "Any divorced woman who menstruated once or twice and whose menses then stopped: she waits nine months; if a pregnancy appears, that is it; otherwise she counts three months after the nine, and then she becomes free" (al-Muwatta 2/582, no. 1212).
Imam Malik said: our position on the divorced woman whose menses stop when her husband divorces her is that she waits nine months; if she does not menstruate, she counts three months; if she menstruates before completing the three months, she takes up the menstruation; if nine months pass without menstruation, she counts three months; likewise for the second menstruation, then the third, after which she has completed the iddah of menstruations; if she does not menstruate, she counts three months and then becomes free, her husband retaining the right of revocation until she becomes free, unless he has pronounced a definitive divorce (al-Muwatta 2/583; al-Mudawwanah al-kubrah 5/427; al-Istidhkar 6/174-175; al-Ishraf 'ala nakt al-masa'il al-khilaf 4/10-11, no. 1364; al-Qawanin al-fiqhiyyah, p. 156; Sharh al-Zurqani 3/273).
Malik's proof is that the woman in doubt counts by months because within that span the pregnancy appears in every case, no pregnancy being able to persist into the ninth month; once it is established that there is neither pregnancy nor menstruation, she is told: "resume three months, as Allah said of those who are not among the women with quru'," by analogy with the minor whose months iddah is interrupted by menstruation: the quru' are made to be resumed. Ibn Qudamah said: we know of no opponent of Umar; Ibn al-Mundhir relates that Umar judged thus between the Muhajirun and the Ansar and that no one denied it. Al-Athram said: I heard Abu Abd Allah (Ahmad) asked about the man who divorces his wife, who menstruates and then sees her menses stop; he said: "I hold to the hadith of Umar: if her menses stop without her knowing the cause, she waits a year." He was told: and if she menstruates before the year? He said: "She returns to the menstruation." He was told: and if her menses stop again without a known cause? He said: "She stays another year." This is the view of all who share our position in the first question: when her menses stopped she became a woman in doubt, and she must move to a full year, for one iddah is not built upon another iddah; likewise, if she menstruated once or twice and then despaired, she moves to three months (al-Mughni 8/90; al-Kafi 3/308; al-Ishraf 'ala madhahib al-'ulama' 5/355-356; Sharh al-Zarkashi 2/535-536).
Ibn Qudamah had also said: if she menstruates after the year and before her marriage, two views exist: either no iddah is owed by her, or the iddah is owed because she is one of the women with quru' and she was able to count before the husband's right attached to her, like the one who menstruates during the year (al-Kafi 3/308).
Second case: her menses stop at the very moment her husband divorces her, for a known or an unknown cause. As for the known cause, such as an illness, breastfeeding or other, the Hanafis, the Shafi'is and the Hanbalis hold that she bears patience until her menses return, then counts the quru', however long the span may be, or reaches the age of menopause, then counts the months; the length of the waiting is not considered. Imam al-Shafi'i relates through his chain that Habban ibn Munqidh divorced his wife once, by whom he had a daughter whom she was nursing; her menses became spaced out, and then Habban fell ill. He was told: if you die, she will inherit from you. He went to Uthman, in the presence of Ali and Zayd ibn Thabit, and asked him. Uthman asked them what they thought; they answered: "We judge that if she dies, she inherits from him, and if he dies, he inherits from her, for she is neither of the women who have despaired of their menses nor of the virgins who have not yet menstruated." Habban returned home, weaned his daughter, and the menses returned: she menstruated twice, and Habban died before the end of the third; Uthman made the wife inherit (reported by al-Bayhaqi in as-Sunan al-Kubra, 7/419). No one opposed them, which establishes a consensus.
Al-Athram relates, through his chain, from Muhammad ibn Yahya ibn Habban, that there were with his grandfather two wives, a Hashemite and an Ansari woman; he divorced the Ansari while she was nursing, a year passed and then he died, and she had not menstruated. She said: I have not had my menses. They brought the dispute before Uthman, who judged the inheritance in her favor; the Hashemite blamed him, and he said: "This is the work of your cousin: it is he who pointed us to this," meaning Ali ibn Abi Talib. This account is weak: it is reported by Ibn Abi Shaybah in al-Musannaf (7/129/1) and by Malik (2/572/43).
The Malikis say: if her menses stopped on account of breastfeeding, she counts the quru' as long as she nurses, whether it be long or short; if the nursing stops, she counts the quru'; if she does not menstruate until a year has elapsed from the end of the nursing, she becomes free. If the time of her menstruation passes without her menstruating and without an excuse preventing it, such as an illness or nursing, the well-known view of the school is that she does not become free until she menstruates or nine months of fulfillment elapse, for the stoppage of the menses without cause is an object of doubt. If they stopped on account of an illness, Ibn al-Qasim relates from Malik that it is a doubt like that of the healthy woman: nine months in the case of death, and in the case of divorce a year, nine months of istibra' and three months of iddah, unlike nursing. Ashhab said: its stoppage through illness is like its stoppage through nursing, with no object of doubt: she becomes free in the case of death after four months and ten days, and in the case of divorce she counts the quru' even if they become spaced out (al-Taj wa-l-iklil 3/172; Mawahib al-jalil 5/381-382; Sharh Mukhtasar Khalil 4/138; Hashiyat al-Dasuqi with al-Sharh al-Kabir 3/413-414; al-Bayan wa-l-tahsil 5/332-333; al-Qawanin al-fiqhiyyah, p. 156).
The Shaykh of Islam Ibn Taymiyyah said: if her menses stopped through illness or nursing, she waits until the cause passes and she menstruates, by the agreement of the scholars; if they stopped without a known cause, then according to the soundest view of the scholars, conforming to what Umar judged, she remains a year and then marries: this is the well-known school of Ahmad and an opinion of al-Shafi'i (Majmu' al-fatawa 34/23). Al-Mirdawi adds: it is related from Ahmad that she counts a year, like the woman whose menses stopped without her knowing the cause (al-Insaf 9/287; Manar al-sabil 3/164).
Second type: the woman who does not know the cause of the stoppage of her menses. The Hanafis and the Shafi'is in the school hold that she waits to menstruate and then counts the quru', or to reach the age of menopause and then counts the months; for Allah only established the months iddah for the woman who has despaired of menses and for the one who has never menstruated, by His words: "And those of your women who have despaired of menstruation: if you doubt, their waiting period is three months, and so for the one who has not yet menstruated" (Surah At-Talaq, 4); now this woman is neither the one nor the other before the span of menopause has elapsed (Bada'i al-Sana'i 3/195; Mukhtasar ikhtilaf al-'ulama' 5/352-353; al-Jawharah al-nirah 5/16; al-Bahr al-ra'iq 4/150; Ikhtilaf al-'ulama' of al-Marwazi, p. 170; al-Umm 5/312; al-Bayan 11/22-23; Rawdat al-talibin 5/706-707; al-Najm al-wahhaj 8/131-132; Mughni al-muhtaj 5/87-88; Tuhfat al-muhtaj 10/19-20; Nihayat al-muhtaj 7/154-156; al-Dibaj 3/555-556).
The Malikis, al-Shafi'i in the earlier position, and the Hanbalis, the choice of the Shaykh of Islam Ibn Taymiyyah, hold that she remains until she knows the purity of her womb and then counts the months: a year, of which nine months, the most frequent duration of pregnancy, to establish the emptiness of the womb, then three months. For the iddah is intended for the purity of the womb: once known, the waiting has no further point; and to say "she waits until menopause" would harm the woman by barring her from marriage, and harm the husband by keeping maintenance and housing upon him: it must therefore be removed. She then counts three months according to all of them, except for a view of some Shafi'is, followed in fatwa by al-Barzali: the three months are included within the nine, to spare women harm, especially the young; al-Azraq said it is permitted to follow him in view of the great hardship of waiting until menopause and the predominance of the presumption of the womb's purity (al-Dibaj 5/556).
This is what the hadith of Umar reported by Malik in al-Muwatta (2/582, no. 1212) expresses: "Any divorced woman who menstruated once or twice and whose menses then stopped: she waits nine months; if a pregnancy appears, that is it; otherwise she counts three months after the nine, and then she becomes free." Imam Malik adds the detail already cited: nine months then three months, and if she menstruates before completing the three months she takes up the menstruation, with the husband's right of revocation until she becomes free, unless there is a definitive divorce (al-Muwatta 2/583; al-Mudawwanah al-kubrah 5/427). Imam al-Bayhaqi said: al-Shafi'i, in the earlier position, criticized those who opposed him and said: "The Commander of the Believers Umar judged thus between the Muhajirun and the Ansar, may Allah be pleased with them, and it was not denied of him; how then can opposing him be permitted?" A third opinion among the Shafi'is says that she waits four years, the maximum duration of pregnancy, and then counts the months as a purely devotional act (al-Hawi al-kabir 11/187-188; al-Bayan 11/22-23; Rawdat al-talibin 5/706-707; al-Najm al-wahhaj 8/131-132; Mughni al-muhtaj 5/87-88; Tuhfat al-muhtaj 10/19-20; Nihayat al-muhtaj 7/154-156; al-Dibaj 3/555-556; see also al-Mughni 8/89-90; al-Kafi 3/308; al-Ishraf 'ala madhahib al-'ulama' 5/355-356; Sharh al-Zarkashi 2/535-536; al-Mubdi' 8/124; al-Insaf 9/285; Kashshaf al-qina' 5/491).
The Shaykh of Islam Ibn Taymiyyah was asked about a young woman who had not reached the age of menopause and whose habit was to menstruate, who drank a medicine by which the blood stopped continuously, and who was then divorced in that state: is her iddah counted by months from the divorce, or does she wait for the age of the women who have despaired? He answered: if she knows the blood will not return, her iddah is three months; if the blood may return as it may not, she waits a year and then marries, as Umar ibn al-Khattab judged for the woman whose menses stop without a known cause; this is the school of the majority, such as Malik and al-Shafi'i. As for whoever says she enters the age of the despairing women, it is a very weak view given the harm it contains: the Law contains nothing of the kind, barring her from marriage at the time she needs it and permitting it to her when she no longer needs it (Majmu' al-fatawa 34/24). He adds: what we have mentioned is the best and the easiest of the jurists' views, and it is on it that Umar and others judged; according to the other view, this woman in doubt would remain in iddah until the age of menopause, staying fifty or sixty full years without marrying: hardship and constraint in religion, and a loss of the interests of the Muslims (Majmu' al-fatawa 34/20).
Third case: her menses become spaced out without an incidental cause. The jurists of the four schools, Hanafis, Malikis, Shafi'is and Hanbalis, agreed: the woman who menstruates but whose menses become spaced out without a cause such as illness or nursing sees her iddah end only with three menstruations, however long they may be; her menses have neither stopped nor been delayed from her habit, and she remains one of the women with quru'. Ibn Qudamah said: we know of no opponent in this case (al-Mughni 8/90-91; Kashshaf al-qina' 5/491; see also Bada'i al-Sana'i 3/195; Ahkam al-Quran 5/352-353; al-Jawharah al-nirah 5/16; al-Bayan 11/22).
To the point that the Malikis say: if the woman's habit is that the qur' only comes to her once a year or more, she counts only the quru' and does not leave the category of the women with cycles; she waits for the menstruation according to her habit, contrary to Tawus, who judged that three months suffice her without waiting for the menstruation. Thus the one whose habit is a menstruation every five years waits: if the time of its coming arrives and it does not come, she becomes free; if it comes, she waits for the time of the second, then of the third; if it does not come, she becomes free. They differed if her habit is a menstruation every ten years: some say she is like the one who waits one or five years; others that she counts a blank year from the day of her divorce, by analogy with the one who menstruates once in her life; others that she counts three months like the despairing woman (al-Taj wa-l-iklil 3/172; Mawahib al-jalil 5/381-382; Sharh Mukhtasar Khalil 4/138; Hashiyat al-Dasuqi with al-Sharh al-Kabir 3/413-414).
Imam Ibn Rushd said: as for the divorced woman who does not menstruate although she is of the age of menstruation, with no doubt of pregnancy and no cause such as nursing or illness, Malik judges that she waits nine months; if she does not menstruate, she counts three months; if she menstruates before completing the three months, she takes up the menstruation and waits; if nine months pass before the second menstruation, she counts three months; if she menstruates before completing the three months of the second year, she waits for the third menstruation; if nine months pass, she counts three months; if she menstruates the third within the three months, she has completed the iddah of menstruations and her iddah is complete, her husband retaining the right of revocation until she becomes free. They differed over the starting point of the nine months in Malik's teaching: some say from the day of the divorce, which is what appears in al-Muwatta; Ibn al-Qasim relates from him: from the day her menses stopped (Bidayat al-Mujtahid 2/68-70).
Abu Hanifah, al-Shafi'i and the majority, regarding the woman whose menses stopped while she has not yet despaired, in the case of revocation, judge that she remains waiting until she enters the age at which one despairs of menses, and then counts the months. Malik's view is narrated from Umar ibn al-Khattab and Ibn Abbas; the majority's view is that of Ibn Mas'ud and Zayd. Malik's support, by way of meaning, is that the iddah only aims at that by which the purity of the womb is established presumptively, as shown by the fact that the pregnant woman may menstruate; the iddah of pregnancy therefore suffices to know the purity of the womb, and then she counts three months, the iddah of the despairing woman. If she menstruates before the end of the year, she receives the ruling of the women who menstruate and counts that qur', then waits for the second qur' or the year until three quru' are complete. The majority, for their part, hold to the apparent meaning of the verse: "And those of your women who have despaired of menstruation: their waiting period is three months" (Surah At-Talaq, 4), whereas the woman of the age of menstruation has not despaired; this view involves hardship and constraint. To say that she counts three months would be good if the despairing woman were understood as the one whose cessation of menses is not certain. The words "if you doubt" refer, according to Malik's interpretation, to the ruling and not to the menstruation: he understood by the despairing woman the one about whom it is definitively judged that she is no longer among the women who menstruate, which happens only through age. Isma'il and Ibn Bukayr, of his companions, hold that the doubt is in the menstruation, the despairing one in the Arabic language being what has not been definitively ruled: they thus matched the interpretation of the verse to Malik's school. As for the difference between what precedes the nine months and what follows them, it is istihsan. And for the woman whose menses stopped for a known cause, such as nursing or illness, Malik's well-known view is that she waits for the menstruation, whether the time be short or long; it is also said that the sick woman is like the one whose menses stopped without cause.
As for the woman with continuous bleeding, her iddah is, according to Malik, one year if she does not distinguish the two bloods; if she distinguishes them, two narrations from him: her iddah is the year, or she acts upon the distinction and counts the quru'. Abu Hanifah said: her iddah is the quru' if she distinguishes, otherwise three months. Al-Shafi'i said: her iddah is by distinction, when the blood separates: the thick red belongs to the menstruation and the yellow to the days of purity; if the blood covers her continuously, she counts the number of the days of her usual menstruation in good health. Malik kept the year because he likened her to the one who does not menstruate while belonging to the women who menstruate; al-Shafi'i kept the distinction on the basis of the Prophet's words to the woman with continuous bleeding: "Leave the prayer the days of your cycles, and when its term has passed, wash the blood," and his words to Fatimah bint Abi Hubaysh: "If it is the blood of menses, it is a black, recognizable blood: refrain from prayer; if it is the other, perform ablution and pray, it is only a vein," reported by Abu Dawud. Those who rule her iddah by months when the bloods are mixed rely on the fact that she most often menstruates every month, and that Allah established the months iddah when the menstruation ceases, its disappearance being like its stoppage.
As for the woman in doubt of pregnancy, the one who perceives in her belly a sensation she takes to be a pregnancy, she waits longer than the maximum duration of pregnancy, and they differed: according to the school four years, according to others five years, and the Zahiris say nine months (Bidayat al-Mujtahid 2/68, 70). As for taking a medicine to bring on the menses, most of the jurists stated explicitly that it is permitted for the woman to take a medicine to bring on her menses and that the iddah ends with the menstruation thus obtained.
The Hanafis stated explicitly that if the woman drinks a medicine and the blood descends within the days of her menstruation, it is a menstruation and the iddah ends with it. Ibn Abidin said: the nursing woman who sees no blood during the span of her nursing sees her iddah end only with menstruation. And in as-Siraj: some masters were asked about a nursing woman who saw no menses and treated herself until she saw a yellow color within the days of menstruation; they answered: it is a menstruation, the iddah ends with it (Hashiyat Ibn Abidin 1/502-503, 3/505, 510; Tanqih al-fatawa al-Hamidiyyah 1/397).
Imam Malik, for his part, disapproved of the woman drinking a medicine to delay her menses. Ibn Rushd said: he disapproved of it for fear that she would do harm to her body. If the woman drinks a medicine to hasten purity out of the menstruation, as when her habit was to see the blood eight days and she uses it after three days and the blood stops, a state of purity is ruled for her. If she drinks a medicine to hasten the coming of the menses before their time, the Malikis stated explicitly that what descends is not a menstruation: she is pure, the iddah does not end thereby and marriage does not become lawful again; she prays and fasts, and makes up the fast without the prayer as a precaution (Mawahib al-jalil 1/365-366; Hashiyat al-Dasuqi 1/268-270; Minh al-jalil 1/166).
Among the Shafi'is, the apparent view is permission, and Allah knows best: al-Nawawi said: if she drinks a medicine for the menses and she menstruates, no make-up is owed by her, that is, the making up of the prayers; likewise if she drinks a medicine and expels a fetus that had breathed, the make-up is not owed according to the sound view, for the suspension of prayer for the menstruating woman or the woman in lochia is a firm duty. His words therefore show that it is not forbidden for her to drink a medicine to bring on the menses (al-Majmu' 2/479; Rawdat al-talibin 1/358).
The Hanbalis stated explicitly that it is permitted for the woman to drink a lawful medicine to cut off the menstruation, in absolute terms, with safety from harm. The judge said: it is only permitted with the husband's permission, like azl (withdrawal), for he has a right in the child; and in al-Insaf: it is the correct view; and in al-Furu': it is supported by Ahmad's word in one of his answers: "The wife asks her husband's permission." It is also said that a man doing this to his wife, making her drink a lawful medicine that cuts off the menses, without her knowledge, tends to prohibition, for it strips her of her absolute right to the intended offspring. It is likewise permitted for the woman to drink a lawful medicine to bring on the menstruation, unless she pursues in it a forbidden aim such as breaking the fast of Ramadan: then it is not permitted (Kashshaf al-qina' 1/218; al-Ikhtiyarat al-'ilmiyyah 1/47; al-Insaf 1/383; Manar al-sabil 1/77).
The Shaykh of Islam Ibn Taymiyyah was asked about a nursing woman whose menses were late, who treated herself for their coming and menstruated three times while she was divorced: does her iddah end? He answered: yes; when the known menstruation comes, she counts by it, just as if she had drunk a medicine that cuts off the menses or spaces them out: that is a state of purity, and just as if she had been hungry, or tired, or if other causes had warmed her nature and stirred the blood, and she menstruated thereby; and Allah knows best (Majmu' al-fatawa 34/23-24).
The scholars agreed: when the wife loses her husband without being pregnant, her iddah is four months and ten days; by the words of Allah, the Most High:
"Those of you who die and leave behind wives: they shall wait by themselves for four months and ten days."
Surah al-Baqarah, 234
Imam Ibn al-Mundhir said: the scholars agreed that the iddah of the free Muslim woman who is not pregnant at her husband's death is four months and ten days, whether the marriage was consummated or not, whether she is a minor who has not reached puberty or an adult woman (al-Ijma' 441; al-Ishraf 5/341). Imam Ibn Rushd said: the Muslims agreed that the iddah of the free woman for her free husband is four months and ten days, by His words: "they shall wait by themselves for four months and ten days" (Surah al-Baqarah, 234) (Bidayat al-Mujtahid 2/72). Imam Ibn Qudamah said: the scholars agreed on this point, whether she is an adult or a minor; and the Prophet said:
It is not permitted for a woman who believes in Allah and the Last Day to mourn a deceased person more than three nights, except for her husband: four months and ten days.Reported by Bukhari and Muslim (muttafaq 'alayh)
This being established, the occurrence of menstruation is not taken into account in the iddah of death according to the generality of the scholars. It is related from Malik that if the marriage was consummated, four months and ten days are owed to her including one menstruation; but following the Book and the Sunnah is sounder, and if the menstruation were counted, she would owe three quru' like the divorced woman: this disagreement belongs specifically to the woman with cycles, for the despairing woman and the minor there is no disagreement.
The ten days counted in the iddah are ten nights with their days: ten days are thus owed together with the nights, according to Malik, al-Shafi'i, Abu Ubayd, Ibn al-Mundhir and the people of opinion. Al-Awza'i said: ten nights and nine days are owed, for the ten serves for the nights, and the days within them enter only as an appendage. The answer: the Arabs give predominance to the feminine noun in numbering, especially over the masculine: they say "three nights" intending the days, as Allah says: "Your sign is that you shall not speak to the people for three whole nights" (Surah Maryam, 10), intending their days, as His words elsewhere show: "Your sign is that you shall not speak to the people for three days except by gesture" (Surah Al Imran, 41), intending the nights with their days. If someone made a vow of retreat for the last ten nights of Ramadan, the nights and the days would be owed by him; and whoever says "we traveled ten days" intends the nights with their days. The ten therefore cannot be moved from the iddah to the permission on the basis of mere doubt (al-Mughni 8/93-94).