Brief Answer:
The risk of breast cancer and fennel seeds is not demonstrated

Detailed Answer:
Hi Pxxxxxxxxxxxxxxxx,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. The form of estrogen in fennel seeds is mixed with many other chemicals and is not a pure estrogen.

2. Cancer causing effects of fennel seeds has not been proven after research.

3. Researchers have concluded that "In humans estragole usually enters the body as a component of fennel tea, or as a food that has been seasoned with herb that contains many other substance like nevadensin, epigallocatechine, other flavonoids, and anethole, that have a protective role and so counterbalance to the possible effect of pure estragole. In this context estragole occurs in the form of an extremely complex phytochemical mixture. If data about single constituent in vivo can be used as basis for statements about a herb, then data about other constituents should also be fully considered, because we think it is the only way to establish definitively if a substance is dangerous or not; and if it is a substance used from many years and in particular subsets of consumers or patients epidemiological data, when available, can help in establishing, together with the real mode of use, the effective risk for consumers."

Therefore it is wrong to believe that fennel seeds has put you at risk of breast cancer. However with a previous history of lumpectomy, it is suggested that you get your annual breast screening done regularly.

Hope your query is answered.
Please do write back if you have any doubts.

Regards,

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