הלכה על בכורות 45:32

Women, who do not pray in the synagogue, do not hear the ḥazan, and therefore must practice one would when praying individually. That is, according to Ashkenazic custom, before beginning Shema she says, “Kel Melekh ne’eman” (“God, faithful King”). Even though women have 252 limbs, as the womb has two doors and two hinges (Bekhorot 45a), since all people have 248 limbs, perhaps it is most important to direct the blessings toward them, and the blessing will then continue to the limbs unique to women (Minḥat Elazar 2:28; Ha-elef Lekha Shlomo OḤ 120).