Is a woman's prayer considered valid if she says the opening takbir (Allahu Akbar) more than twice or thrice in a fard (obligatory) prayer?

If a woman intentionally repeats Al-Fatihah in prayer, she has fallen into innovation (bid'ah), and she should be advised that her action is contrary to Islamic law. Her prayer is valid. However, if her action is due to excessive whispering (waswas), then there is no sin upon her, and she should be advised not to pay attention to the whisperings and to increase in seeking refuge (with Allah).