1. It is permissible to start the fast when one is junub. i.e. One had a wet dream or had sexual relation before sehri. So one may take ghusl after sehri provided he or she don`t swallow water. So it is advisable to gargle and wet the mouth and nostrils before end of sehri. And then take the full shower before perfoming Fajr salaah.
2. Know that menstruation or regular monthly discharge of blood in women break the fast. It is incumbent upon a menstruating woman to eat or drink and break her fast immediately after she is sure that she is menstruating.
If she is in doubt, then she may wait until sure that it is her menstruation.
NOTES: A haiz is a minimum of 3 days bleeding. It has a maximum of 10 days bleeding. After 10 days bleeding, one should shower and pray and live normally. She will have a minimum of 15 days of praying days.
If she doesn’t have a minimum of 15 days before her next bleeding she should consult a scholar
Also Women who missed fasts because of menstruation should replace her fasts later on after Ramadhaan and better before other Ramadhaan. Salaah missed during menstruation should not be replaced.
3. If haiz comes any time after sehri, then this fast is broken and one should replace this fast later on. It is haraam to persist on niyah of fasting when haiz comes, even 5 minute before Iftaar. One should eat and leave fasting.
4. A woman who was in haiz and now she becomes paak and take her shower during the day or any time after sehri, then it is wajib for her not to eat or drink the rest of the day. Note that this day will not be counted as a fast and hence should be replaced later on. Note that even if she becomes paak after Sehri any time, she still need to replace that fast later on.
5. In any case, one cannot have intention to keep fast during haiz or nifaas(post natal bleeding).
6. It is better for a menstruating woman or a sickly person to eat in private and not in public during Ramadhaan.
7. What solution for those who fasts qadas for years and have not been able to replace them?
First of all know that it is farz for a lady or a girl to replace her missed fast during menstruation or nifaas(post natal bleeding). Fidyah is not applicable for them. Fidyah is applicable only to those sick people who does not have hope to be healthy so as to replace their fasts. It is important to replace fasts missed during menses.
The sunnah teaches us to replace them as soon as possible. But one may postpone replacement until before next Ramadhaan.
Reported in Bukhari from our mother Hazrat Aisha r.a. was to replace her fasts but could not due to her khidmat to the beloved prophet SAW until Sha`baan comes and she would accompany Him replacing her missed fasts.
But we are aware that some ladies have not been able to replace their fasts for years now. And that their qadahs have been numbered in hundreds now.
The first solution is that these ladies should not fast nafil during the year and rather should replace their farzs fasts that they missed from years.
If you have forgot the number of fasts missed, then do your qadah niyah from the night as such: O Allah, I would fast tomorrow my first fast that I missed during my life. Then do niyah of 2nd…..Note that it is important to do niyah before Sehri time for all qadas fasts.
Thirdly, if you can fast only in Ramadhaan and that you don`t fast at all outside Ramadhaan, and that your missed fasts have accumulated for years now, then it is permissible for you to consult a gynaecologist so that she may prescribe medicine to retard menses or postpone it. And like that, you may fast whole Ramadhaan. But still know that there are hormonal side effects of these medicines and hence it is better to opt A and B options. And still know that in any case, you would still need to replace past missed fasts. Wallahou A`lam bissawaab.