Honestly, I'd ask your OB about this one kasi bawat pregnancy is different, pero personally I'd be extra cautious with ankgas or joyrides at 18 weeks, ang bumps and sudden stops talaga ay risky for the baby, and if may accident man kahit minor lang, mas vulnerable ka pa. A few of us moms sa circle namin, some switched to safer transport during pregnancy or nag-adjust ng schedule to minimize risk, kaya best talaga if you can explore other options or at least confirm with your doctor na okay lang talaga for your specific situation!