The subways are crowded and it's often difficult to find a seat.
For pregnant women, it can be a matter of safety and health.
Christine Serdjenian Yearwood created UP-STAND to promote the cause.
She commuted from Queens during her pregnancy and started the campaign in November 2015. She hopes the MTA will work with her to distribute buttons which also can be worn by those who are volunteering to give up their seats.
Other transit systems have piloted some programs that set off sensors when women with a beacon enter the train.