Q. Can a woman listening to Kerias Hatorah in shul, when needed by the necessities of her children or similar exit in the middle of the reading, especially in the Shabbosim with a double parsha, when the aliyos are long.
A. Shulchan Aruch (O,H. 146:1) and Mishna Berura rule that it is prohibited for men to leave the shul from the time the Sefer Torah was opened for the reading, until the aliya ends and it is closed.
Kovetz Teshuvos (3: 48) writes that in our days, when many women understand the Kerias Hatora, if they are then in shul, they should remain there as men do.
However, in need Kaf Hachaim (146: 2) and others rule that they can exit even in the middle of the reading or when the Sefer Torah is still open.
Horav Shlomo Miller's Shlit'a opinion is similar.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a