http://revach.net/article.php?id=3990

Section: Halacha   Category: Tefila
Rav Shlomo Zalman Auerbach - When A Woman Misses Zman Tefila
Zman Tefilas Shmoneh Esrei in the morning is until 4 hours after the day starts (subject to the machlokes Gra and Mogen Avrohom whether that is Netz HaChamah or Alos HaShachar).  If someone doesn't daven before four hours he may daven until Chatzos bidieved.  Some poskim hold that if he intentionally did not daven before four hours he may not daven afterward until chatzos.  What happens when a woman doesn't have a chance to daven before four hours, should she daven until Chatzos?

Rav Shlomo Zalman Auerbach (Halichos Shlomo 8:42) says that while the minhag of the world is that a woman does daven after four hours until chatzos, nevertheless he says that it is preferable that she does not do so.  His reasoning is that the Chiyuv Tefila Min Hatorah is to daven once a day and the Rabbanan were Misaken Tefila three times a day.  The Mishna Brura (106:4) says that women should daven twice a day, both Shacharis and Mincha, while the Mogen Avrohom holds that women only need to say a short tefila once a day.

Therefore says Rav Shlomo Zalman since she only really needs to daven once a day according to the Mogen Avrohom, it is better not to daven during a questionable time.  Better to wait for Zman Mincha and daven then, even though given the chance, Shacharis is preferable to Mincha.  
 
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