Hindi mandatory, pero highly recommended talaga ng doctors, lalo na ngayon with all the variants around! A few of my pregnant mum friends got the flu shot kaya safe sila at ng babies nila, dahil nakakaapekto talaga ang flu pag buntis. Best talaga na konsultahin mo ang OB mo directly since every pregnancy is different, pero sa majority ng cases, pinapayagan nila at mas encouraged pa talaga