Print Overview Polyhydramnios Enlarge image Close Polyhydramnios Polyhydramnios In polyhydramnios, excessive amniotic fluid accumulates in the uterus during pregnancy. Mild cases of polyhydramnios may go away on their own. Severe cases may require treatment. Polyhydramnios (pol-e-hi-DRAM-nee-os) is the excessive accumulation of amniotic fluid — the fluid that surrounds the baby in the uterus during pregnancy. Polyhydramnios occurs in about 1 to 2 percent of pregnancies. Most cases of polyhydramnios are mild and result from a gradual buildup of amniotic fluid during the second half of pregnancy. Severe polyhydramnios may cause shortness of breath, preterm labor, or other signs and symptoms. If you're diagnosed with polyhydramnios, your health care provider will carefully monitor your pregnancy to help prevent complications. Treatment depends on the severity of the condition. Mild polyhydramnios may go away on its own. Severe polyhydramnios may require closer monitoring.Products & ServicesA Book: Mayo Clinic Family Health Book, 5th EditionA Book: Mayo Clinic Guide to a Healthy PregnancyNewsletter: Mayo Clinic Health Letter — Digital EditionShow more products from Mayo Clinic SymptomsPolyhydramnios symptoms result from pressure being exerted within the uterus and on nearby organs. Mild polyhydramnios may cause few — if any — signs or symptoms. Severe polyhydramnios may cause: Shortness of breath or the inability to breathe Swelling in the lower extremities and abdominal wall Uterine discomfort or contractions Fetal malposition, such as breech presentation Your health care provider may also suspect polyhydramnios if your uterus is excessively enlarged and he or she has trouble feeling the baby. Request an appointment CausesSome of the known causes of polyhydramnios include: A birth defect that affects the baby's gastrointestinal tract or central nervous system Maternal diabetes Twin-twin transfusion — a possible complication of identical twin pregnancies in which one twin receives too much blood and the other too little A lack of red blood cells in the baby (fetal anemia) Blood incompatibilities between mother and baby Infection during pregnancy Often, however, the cause of polyhydramnios isn't clear. ComplicationsPolyhydramnios is associated with: Premature birth Premature rupture of membranes — when your water breaks early Placental abruption — when the placenta peels away from the inner wall of the uterus before delivery Umbilical cord prolapse — when the umbilical cord drops into the vagina ahead of the baby C-section delivery Stillbirth Heavy bleeding due to lack of uterine muscle tone after delivery The earlier that polyhydramnios occurs in pregnancy and the greater the amount of excess amniotic fluid, the higher the risk of complications. By Mayo Clinic Staff Request an appointment Diagnosis & treatment April 06, 2023 Print Show references Beloosesky R, et al. Polyhydramnios. https://www.uptodate.com/contents/search. Accessed Sept. 30, 2017. Polyhydramnios. Merck Manual Professional Version. http://www.merckmanuals.com/professional/gynecology-and-obstetrics/abnormalities-of-pregnancy/polyhydramnios. Accessed Sept. 30, 2017. Gabbe SG, et al. Amniotic fluid disorders. In: Obstetrics: Normal and Problem Pregnancies. 7th ed. Philadelphia, Pa.: Saunders Elsevier; 2017. https://www.clinicalkey.com. Accessed Sept. 30, 2017. Polyhydramnios (too much amniotic fluid). National Health Service. http://www.nhs.uk/conditions/polyhydramnios/Pages/polyhydramnios.aspx. Accessed Oct. 1, 2017. Butler Tobah YS (expert opinion). Mayo Clinic, Rochester, Minn. Oct. 11, 2017. Related Polyhydramnios Associated Procedures Amniocentesis Glucose challenge test Products & Services A Book: Mayo Clinic Family Health Book, 5th Edition A Book: Mayo Clinic Guide to a Healthy Pregnancy Newsletter: Mayo Clinic Health Letter — Digital Edition Show more products and services from Mayo Clinic PolyhydramniosSymptoms&causesDiagnosis&treatment Advertisement Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. Advertising & Sponsorship Policy Opportunities Ad Choices Mayo Clinic Press Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. Mayo Clinic on Incontinence - Mayo Clinic PressMayo Clinic on IncontinenceThe Essential Diabetes Book - Mayo Clinic PressThe Essential Diabetes BookMayo Clinic on Hearing and Balance - Mayo Clinic PressMayo Clinic on Hearing and BalanceFREE Mayo Clinic Diet Assessment - Mayo Clinic PressFREE Mayo Clinic Diet AssessmentMayo Clinic Health Letter - FREE book - Mayo Clinic PressMayo Clinic Health Letter - FREE book CON-20339036 Patient Care & Health Information Diseases & Conditions Polyhydramnios