After getting a cone biopsy, my cervix has nearly closed itself.
Because of this, during every menstruation, the blood accumulates in the uterus.
ご質問ありがとうございます。
"After getting a cone biopsy,"=「円錐切除をした後、」
"my cervix has nearly closed itself."=「私の子宮口はほぼ閉じてしまいました。」
"Because of this, during every menstruation,"=「それにより、生理ごとに」
"the blood accumulates in the uterus."=「子宮に血が溜まります。」
ご参考になると幸いです。