It may mean your placenta will deteriorate the farther along you get, it's the food source for your baby in the womb so it's very important it's working properly. Are they monitoring it? Scans more often, more often appts? It may mean an earlier delivery depending on how fast it's aging and how well baby is growing.
I had it late in pregnancy and ended up having to be induced almost a month before my due date because the baby wasn't being fed and needed nutrition. I ended up with a 4.7 lbs little girl who was completely healthy by C section after 24 hr Labour. I would make sure u ask the doctor about it and make sure the baby is growing properly. Good luck I hope this helped.