Matthew 24:19-22
How terrible it will be for pregnant women and for mothers nursing their babies in those days.
And pray that your flight will not be in winter or on
the Sabbath.
For that will be a time of greater horror than anything the world has ever seen or will ever see again.
In fact, unless that time of calamity is shortened, the entire human race will be destroyed. But it will be shortened for the sake of God's chosen ones.   

"Pray ye that your flight be not in the winter; neither on the Sabbath day," Christ said. He who made the Sabbath did not abolish it, nailing it to His cross. The Sabbath was not rendered null and void by His death. Forty years after His crucifixion it was still to be held sacred. For forty years the disciples were to pray that their flight might not be on the Sabbath day.

Jeremiah 30:5-7
    "This is what the Lord says: I have heard the people crying; there is only fear and trembling.
Now let me ask you a question: Do men give birth to babies? Then why do they stand there, ashen-faced, hands pressed against their sides like women about to give birth?
In all history there has never been such a time of terror. It will be a time of trouble for my people Israel. Yet in the end, they will be saved!