The question below was submitted to www.yoatzot.org, Nishmat's Women's Health and Halacha (Jewish Law) website for the lay public.
"I recently had a mastectomy with immediate reconstruction and have not been able to go to the mikveh because of the wound. I saw the surgeon again yesterday and asked about this and she is still very worried about infection and implied it could be a few months until I could immerse. I asked her - what about a lake, ocean, etc and she still did not agree. I assume these things come up all the time - what can I do?"
When dealing with mikveh observant women, this very important question is best dealt with as part of routine discharge instructions. In order to answer the question, it is important to understand mikveh construction and maintenance. The actual water in which women immerse is tap water from the local water supply. The immersion pool is made halachically valid by linkage to enclosed collections of rain water. There are two general methods by which the water in the immersion pool is kept sanitary. The first is by adding chlorine (or bromine) and periodic changing of the water. The second is by ultrafiltration mechanisms. The water in the mikveh is thus much cleaner than that of any natural body of water.
A modern mikveh will meet all standards of the local health department for public bathing facilities. For women at higher risk, special arrangements can be made. The pool can be drained of all the water and wiped down with a disinfectant solution. For halachic reasons, it has to be carefully dried prior to refilling and thus a thorough job will always be done. The pool is then refilled with fresh clean tap water. The high risk woman will be the first to immerse in the pool before others do so. [On the other hand, if a woman has a potentially infectious condition, special arrangements can be made for her to be the last to immerse before the pool is drained and disinfected].
Many women prepare for mikveh immersion in preparation rooms provided at the facility. While these are kept clean, the fact that they are used by many women does increase the chance of infection for women at high risk. However, a woman may do all her preparations at home and high risk woman should do so. The custom for women who prepare at home is to take a quick shower again at the mikveh. For the high risk woman, this custom can be put aside as long as her hair is still damp.
There are various widespread customs regarding the number of times a woman dunks under the water of the mikveh. Halachically, a single immersion for even a few seconds is sufficient. A woman at high risk can be instructed to limit herself to this minimum and thus further decrease her exposure to the water.
It is therefore hard to imagine a situation where a woman who is allowed to shower at home would not be allowed to immerse in the mikveh. Every mikveh has a person who is responsible for maintenance. A member of the health care team can speak to this person directly to assure that all precautions are taken for a given situation. If a particular mikveh is unable to accommodate all the needed adjustments, they should be able to suggest other facilities that can. The importance of allowing a woman undergoing oncological treatment the physical closeness of her husband should justify the effort needed to make the arrangements.
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