Two vessel cord??

Grace. • 👼🏼💕💙 // Keagan 1/31/2020 🌈❤️ // Ethan 9/14/2021 ☀️💚

My doctor called and said that I have a two vessel cord and a low placenta so I have to get another ultrasound done tomorrow to make sure baby is getting enough nutrients. Anybody get diagnosed with this? What does it mean?