In the name of Allah, the Most Merciful, Bestower of Mercy.
Answer: The waters that exit from the private parts of a woman are of three types. The first type is maniyy (منيّ), and it is the sudden discharge of fluid that is experienced by men and by women as a product of sexual intimacy, that gives them a pleasure that encompasses the whole body as it exits it. This fluid (maniyy) is pure according to the most correct saying of the scholars, but it does require that the woman performs a complete ghusl (i.e. bathes) due to its occurrence. The second type is madhī (مذْي), and this is discharge that exits during foreplay, and while thinking of sexual intimacy or desiring it. Madhī is impure by the agreement of the scholars―its discharge necessitates that wuḍū is renewed―and the washing of the private parts from madhī is required before the wuḍū is performed, and also to trickle or sprinkle water onto whatever of the madhī falls onto the garments.
The third type is ruṭūbah (رطوبة), which is the wetness and dampness of the private part of a woman. Concerning this, there is differing among the scholars concerning whether is pure or impure (najisah). Those who hold that it is impure give the reason that this discharge exits from the same place as the urine, madhī and menstrual blood therefore it is likewise impure. Shaikh Muhammad Ibn ‘Uthaymīn stated: “I seek Allah’s guidance―and I say that the wetness (ruṭūbah discharge) of the private part of a woman is pure (ṭāhirah).” Therefore, if this wet discharge is not due to foreplay, and without thoughts of intimacy or desire for it―instead it is similar to sweat, then this is not harmful according to the correct view of the scholars, because it is pure, and therefore does not require washing the private area [or the garment], nor does it require renewing the wuḍū (ablution). And with Allah is success and guidance.
Source: Fath Ar-Rabb Al-Wudūd Fī Fatāwā war-Rasā’il war-Rudūd 1/180, of Shaikh Ahmad Ibn Yahyā An-Najmī (may Allah’s mercy be upon him).