Do the secretions from a woman’s uterus become najis (impure) when mixed with madhiy (prostatic fluid)?
Question

Do the secretions from a woman’s vagina become najis (impure) when mixed with madhiy (prostatic fluid)?
Praise be to Allah.Firstly:
We have previously explained that the secretions that come from a woman’s uterus are pure (taahir), in the answer to question no. 50404 .
Secondly:
The textual evidence proves that madhiy is impure (najis) and we are instructed to cleanse ourselves of it.
It was narrated that ‘Ali (may Allah be pleased with him) said: I was a man who frequently emitted madhiy, so I told a man to ask the Prophet about that (blessings and peace of Allah be upon him), because his daughter was married to me. So he asked him, and he said: “Do wudoo’, and wash your penis.” Narrated by al-Bukhaari (269) and Muslim (303).
‘Abd ar-Razzaaq narrated in al-Musannaf (1/159) from ath-Thawri, from Mansoor, from Mujaahid, that Ibn ‘Abbaas said regarding madhiy (prostatic fluid), wadiy (a thick white fluid which is emitted after passing urine) and maniy (semen): Ghusl is required for maniy, and wudoo’ is required for madhiy and wadiy; the man should wash the tip of his penis and do wudoo’.
This is the view of the majority of scholars, to the extent that some of them said that there is consensus on this matter.
Ibn ‘Abd al-Barr (may Allah have mercy on him) said:
Regarding the madhiy which is well known…
It is a matter on which there is consensus, and there is no difference of opinion among the Muslims that it is obligatory to do wudoo’ for it, and it is obligatory to wash it off, because it is impure (najis). "At-Tamheed (21/207)"
Thirdly:
Any liquid other than water is to be regarded as being like water when something impure (najis) is mixed with it, so it becomes impure if the impure substance remains there and its effects are visible in it. And the liquid is deemed to be pure if no change occurs in it and no trace of the impurity is visible.
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:
The correct view regarding water is that it is not deemed to be impure unless it changes completely or is mostly changed – this ruling is also correct with regard to other liquids.
Generally speaking, regarding water and other liquids as being the same is possible in these two scenarios [mentioned above]. This is what may be understood from the religious texts and may be worked out on the basis of analogy with regard to the issue of removing impure substances, and with regard to the issue of them being mixed with water and other liquids.
Whoever examines the principles [regarding impurity] on which there is consensus, and the shar‘i considerations that form the basis of shar‘i rulings, it will become clear to him that this is the soundest view, because deeming water and other liquids to be impure (najis) without them having been changed by the impurity is far removed from the apparent meaning of the text and from conclusions based on analogy. "Majmoo‘ al-Fataawa (21/508)"
Based on that, and based on the fact that the madhiy and the secretions come from the same place, madhiy makes the secretions impure, especially if there is a great deal of madhiy and the secretions are not of a great amount that would let the madhiy be absorbed in them and make its characteristics disappear.
Ar-Ruhaybaani (may Allah have mercy on him) said:
If the impurity is mixed with something else, and it is not limited, then the whole thing becomes haraam and impure. The same applies if it is mixed with a liquid, because of the report.
End quote from Mataalib Ooli an-Nuha (1/239); see also: Kashshaaf al-QInaa‘ (1/188) and al-Insaaf by al-Mirdaawi (1/344).
Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him) said:
A very small amount of water will be affected by impurity (najaasah) in most cases, so it should be poured away and one should be cautious with it. Hence it is proven that the Prophet (blessings and peace of Allah be upon him) said: “If a dog licks the vessel of one of you, let him pour out its contents, then wash it seven times.” Narrated by Muslim in his Saheeh. That is only because the vessels that people use are usually small, so the contents will be affected by a dog licking them, and by other impurities, even if they are small. So it is obligatory to pour out the contents if any impurity falls into the vessel, so as to be on the safe side and to avoid dubious matters, because the Prophet (blessings and peace of Allah be upon him) said: “Leave that which makes you doubt for that which does not make you doubt”; and he (blessings and peace of Allah be upon him) said: “The one who avoids dubious matters has taken precautions to protect his faith and his honour.” "Majmoo‘ Fataawa wa Maqaalaat ash-Shaykh Ibn Baaz (10/16-17)"
And Allah knows best.