Thank you for reaching out to us.
Halachic sources describe three possible definitions of hargashah: a sensation of the uterus opening, or of the whole body shaking, or of liquid flowing inside the vaginal canal (not of liquid exiting the body).
Establishing a chazakah is relevant when a woman commonly experiences either of the first two sensations–of the uterus opening, or of the whole body shaking–as a potential precursor to bleeding. The sensation of internal flow is debated, and this halacha does not apply to it.
Since women are not usually aware of having these two sensations, it is rare for us to recommend attempting to establish a chazakah as described to you.
Please let us know if we can be of further assistance.
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