Pregnant lady considered as 2 pax for ride sharing?

My family and I were recently told off by Gojek driver in our recent trip. Me, my mom, my brother and his girlfriend boarded a Gojek car, and the driver asked if I’m pregnant. As soon as I said yes, he said we exceeded the 4 passengers cap. I was confused initially and he then said pregnant lady considered as 2 pax. My bro and the gf have to alight the car and book a separate car instead. I couldn’t find any information online and the Gojek customer support was not very helpful in clarifying. Anyone has similar experience and is it true that pregnant lady considered as 2 pax?