The children have come to the birth, and there is no strength to bring forth; come to the birth
Figuratively, by extension: a crisis has been reached. They have reached distress and no longer have the strength to continue (mashber means the situation right before birth or the emergence of the baby from its mother's womb).
(“And they said to him, Thus says Hezekiah: This day is a day of trouble, and of rebuke, and of disgrace; for the children have come to the birth, and there is no strength to bring forth.” - Isaiah 37:3 (the king Hezekiah’s messengers to the prophet Isaiah); and also: “And a time of trouble as of a woman in labor and children/ have come to the birth and there is no strength to give birth/ and if I lack food and drink/ your name is pleasant in my mouth as provision.” - Yehuda Halevi, ‘To You, My Soul’)
Translation
Expression (Hebrew)
בָּאוּ בָּנִים עַד מַשְׁבֵּר וְכֹחַ אֵין לָלֶדֶת, בָּא עַד מַשְׁבֵּר
Definition (Hebrew)
בִּמְלִיצָה בְּהַשְׁאָלָה: הִגִּיעַ מַצָּב מַשְׁבֵּר. הִגִּיעוּ לִמְצוּקָה וְאֵין לָהֶם יוֹתֵר כֹּחַ לְהַמְשִׁיךְ ("מַשְׁבֵּר" בַּמִּקְרָא= מַצָּב הַסָּמוּךְ לְלֵדָה אוֹ יְצִיאַת הַתִּינוֹק מִבֶּטֶן אִמּוֹ).
("וַיֹּאמְרוּ אֵלָיו כֹּה אָמַר חִזְקִיָּהוּ יוֹם צָרָה וְתוֹכֵחָה וּנְאָצָה הַיּוֹם הַזֶּה כִּי בָּאוּ בָנִים עַד מַשְׁבֵּר וְכֹחַ אַיִן לְלֵדָה"- יְשַׁעְיָהוּ לֵז ג (שְׁלִיחֵי הַמֶּלֶךְ חִזְקִיָּה לַנָּבִיא יְשַׁעְיָהוּ), וְכֵן: "וְעֵת צָרָה כְּמַבְכִּירָה וּבָנִים/ עֲדֵי מַשְׁבֵּר וְאֵין כֹּחַ לְלֵדָה/ וְאִלּוּ אֶחְסָר מַאֲכָל וּמִשְׁתֶּה/נָעִים שִׁמְךָ בְּפִי אָשִׂים לְצִדָּהּ"- יְהוּדָה הַלֵּוִי/ לְךָ נַפְשִׁי)