Surah At-Talaq, Verse 4

وَٱلَّٰٓـِٔي يَئِسۡنَ مِنَ ٱلۡمَحِيضِ مِن نِّسَآئِكُمۡ إِنِ ٱرۡتَبۡتُمۡ فَعِدَّتُهُنَّ ثَلَٰثَةُ أَشۡهُرٖ وَٱلَّٰٓـِٔي لَمۡ يَحِضۡنَۚ وَأُوْلَٰتُ ٱلۡأَحۡمَالِ أَجَلُهُنَّ أَن يَضَعۡنَ حَمۡلَهُنَّۚ وَمَن يَتَّقِ ٱللَّهَ يَجۡعَل لَّهُۥ مِنۡ أَمۡرِهِۦ يُسۡرٗا٤

wa-allāī ya-is'na mina l-maḥīḍi min nisāikum ini ir'tabtum faʿiddatuhunna thalāthatu ashhurin wa-allāī lam yaḥiḍ'na wa-ulātu l-aḥmāli ajaluhunna an yaḍaʿna ḥamlahunna waman yattaqi l-laha yajʿal lahu min amrihi yus'ran

And those who no longer expect menstruation among your women - if you doubt, then their period is three months, and [also for] those who have not menstruated. And for those who are pregnant, their term is until they give birth. And whoever fears Allāh - He will make for him of his matter ease.