How can Voltarol Ampoules containing diclofenac sodium affect amniotic fluid levels from the 20th week of pregnancy?

From week 20, Voltarol Ampoules (diclofenac sodium) may reduce amniotic fluid through foetal renal dysfunction, sometimes shortly after starting and usually reversibly after stopping; consider antenatal monitoring after several days, discontinue if oligohydramnios occurs, and use only if clearly necessary in the second trimester, with use contraindicated in the third trimester.