Is the ablution of a pregnant woman who feels like vomiting when rinsing her mouth and sometimes omits it accepted?

Vomiting does not invalidate ablution (wudu’). Rinsing the mouth (madmadah) and sniffing water into the nose (istinshaq) are two sunnah acts in ablution, according to the more preponderant opinion. Therefore, omitting them does not invalidate ablution, and prayer performed with such ablution is valid, although it is more cautious to perform them.