CANADA - 2016/01/21: Prescription pills in a yellow bottle over a wooden table with selective depth of field. (Photo by Roberto Machado Noa/LightRocket via Getty Images) The agency warns that women who are 20-weeks pregnant or later risk serious health problems if they use nonsteroidal anti-inflammatory drugs, otherwise known as NSAIDs.The drugs are used to relieve pain and include medicines such as aspirin, ibuprofen, naproxen, diclofenac, and celecoxib.Doctors said using the drugs can cause unborn babies to produce low levels of amniotic fluid in their kidneys.