1、Intrauterine vaccination refers to the administration of a vaccine to a fetus through the transplacental route.
子宫内免疫是指通过胎盘路线向胎儿接种疫苗。

2、Transplacental transmission of infection can occur during pregnancy, potentially affecting the health of the fetus.
感染的通过胎盘传播可能发生在妊娠期间，可能影响胎儿的健康。