Can stress affect the zygote?

This may sound nuts but we’re ttc #2 and I’m ovulating today or tomorrow but at the same time I’ve been navigating a serious crisis with a family member. I don’t really want to put our plans to ttc on hold but I wonder if this high level of stress and anxiety I’m feeling and will probably continue to feel over the next week could affect the pregnancy from fertilization, or if that’s really too early for stress to take a toll on the soon-to-be fetus?