Close
New

Medscape is available in 5 Language Editions – Choose your Edition here.

 

Polyhydramnios and Oligohydramnios

  • Author: Brian S Carter, MD, FAAP; Chief Editor: Ted Rosenkrantz, MD  more...
 
Updated: Jan 07, 2015
 

Background

The amniotic fluid that bathes the fetus is necessary for its proper growth and development. It cushions the fetus from physical trauma, permits fetal lung growth, and provides a barrier against infection. Normal amniotic fluid volume varies. The average volume increases with gestational age, peaking at 800-1000 mL, which coincides with 36-37 weeks' gestation. An abnormally high level of amniotic fluid, polyhydramnios, alerts the clinician to possible fetal anomalies. Inadequate volume of amniotic fluid, oligohydramnios , results in poor development of the lung tissue and can lead to fetal death.

In pregnancies affected by polyhydramnios, approximately 20% of neonates are born with a congenital anomaly of some type; therefore, the delivery of these newborns in a tertiary care setting is preferred. This article presents the causes, outcomes, and treatments of polyhydramnios and oligohydramnios, as well as their effects on the developing fetus and neonate.

Next

Pathophysiology

Rupture of the membranes is the most common cause of oligohydramnios. However, because the amniotic fluid is primarily fetal urine in the latter half of the pregnancy, the absence of fetal urine production or a blockage in the fetus' urinary tract can also result in oligohydramnios. Fetal swallowing, which occurs physiologically, reduces the amount of fluid, and an absence of swallowing or a blockage of the fetus' GI tract can lead to polyhydramnios.

Previous
Next

Epidemiology

Frequency

United States

Oligohydramnios occurs in 4% of pregnancies, and polyhydramnios occurs in 1% of pregnancies.

Mortality/Morbidity

See the list below:

  • Chamberlin used ultrasonography to evaluate the perinatal mortality rate (PMR) in 7562 patients with high-risk pregnancies.[1] The PMR of patients with normal fluid volumes was 1.97 deaths per 1000 patients. The PMR increased to 4.12 deaths per 1000 patients with polyhydramnios and 56.5 deaths per 1000 patients with oligohydramnios.
  • Preterm labor and delivery occurs in approximately 26% of mothers with polyhydramnios. Other complications include premature rupture of the membranes (PROM), abruptio placenta, malpresentation, cesarean delivery, and postpartum hemorrhage.[2]
  • Studies show an increased risk of associated fetal anomalies in more severe forms of polyhydramnios. In a series in 1990, 20% of cases of polyhydramnios involved associated fetal anomalies, including problems of the GI system (40%), CNS (26%), cardiovascular system (22%), or genitourinary system (13%).[3] Among these cases of polyhydramnios, multiple gestations occurred in 7.5%, 5% were due to maternal diabetes, and the remaining 8.5% were due to other causes. However, at least 50% of the patients had no associated risk factors.
  • The mortality rate in oligohydramnios is high. The lack of amniotic fluid allows compression of the fetal abdomen, which limits movement of its diaphragm. In addition to chest wall fixation, the lack of amniotic fluid flowing in and out of the fetal lung leads to pulmonary hypoplasia. Oligohydramnios is also associated with meconium staining of the amniotic fluid, fetal heart conduction abnormalities, umbilical cord compression, poor tolerance of labor, lower Apgar scores, and fetal acidosis. In cases of intrauterine growth restriction (IUGR), the degree of oligohydramnios is often proportional to growth restriction, is frequently reflective of the extent of placental dysfunction, and is associated with a corresponding increase in the PMR.
  • In twin gestation with twin-to-twin transfusion, polyhydramnios may occur in the recipient twin, and oligohydramnios may occur in the donor. This complication is associated with high morbidity and mortality rates.

Age

No age variables are recognized.

Previous
 
 
Contributor Information and Disclosures
Author

Brian S Carter, MD, FAAP Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Attending Physician, Division of Neonatology, Children's Mercy Hospital and Clinics; Faculty, Children's Mercy Bioethics Center

Brian S Carter, MD, FAAP is a member of the following medical societies: Alpha Omega Alpha, American Academy of Hospice and Palliative Medicine, American Academy of Pediatrics, American Pediatric Society, American Society for Bioethics and Humanities, American Society of Law, Medicine & Ethics, Society for Pediatric Research, National Hospice and Palliative Care Organization

Disclosure: Nothing to disclose.

Coauthor(s)

Roland L Boyd, DO Neonatologist, Section of Neonatology, Neonatal Services, Ltd

Roland L Boyd, DO is a member of the following medical societies: American Academy of Osteopathy, American Academy of Pediatrics, American College of Osteopathic Pediatricians

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

David A Clark, MD Chairman, Professor, Department of Pediatrics, Albany Medical College

David A Clark, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Pediatrics, American Pediatric Society, Christian Medical and Dental Associations, Medical Society of the State of New York, New York Academy of Sciences, Society for Pediatric Research

Disclosure: Nothing to disclose.

Chief Editor

Ted Rosenkrantz, MD Professor, Departments of Pediatrics and Obstetrics/Gynecology, Division of Neonatal-Perinatal Medicine, University of Connecticut School of Medicine

Ted Rosenkrantz, MD is a member of the following medical societies: American Academy of Pediatrics, American Pediatric Society, Eastern Society for Pediatric Research, American Medical Association, Connecticut State Medical Society, Society for Pediatric Research

Disclosure: Nothing to disclose.

Additional Contributors

Ted Rosenkrantz, MD Professor, Departments of Pediatrics and Obstetrics/Gynecology, Division of Neonatal-Perinatal Medicine, University of Connecticut School of Medicine

Ted Rosenkrantz, MD is a member of the following medical societies: American Academy of Pediatrics, American Pediatric Society, Eastern Society for Pediatric Research, American Medical Association, Connecticut State Medical Society, Society for Pediatric Research

Disclosure: Nothing to disclose.

References
  1. Chamberlain PF, Manning FA, Morrison I, et al. Ultrasound evaluation of amniotic fluid volume. II. The relationship of increased amniotic fluid volume to perinatal outcome. Am J Obstet Gynecol. 1984 Oct 1. 150(3):250-4. [Medline].

  2. Rosenberg VA, Buhimschi IA, Dulay AT, Abdel-Razeq SS, Oliver EA, Duzyj CM, et al. Modulation of Amniotic Fluid Activin-A and Inhibin-A in Women With Preterm Premature Rupture of the Membranes and Infection-Induced Preterm Birth. Am J Reprod Immunol. 2011 Oct 13. [Medline].

  3. Ben-Chetrit A, Hochner-Celnikier D, Ron M, Yagel S. Hydramnios in the third trimester of pregnancy: a change in the distribution of accompanying fetal anomalies as a result of early ultrasonographic prenatal diagnosis. Am J Obstet Gynecol. 1990 May. 162(5):1344-5. [Medline].

  4. Pri-Paz S, Khalek N, Fuchs KM, Simpson LL. Maximal Amniotic Fluid Index as a Prognostic Factor in Pregnancies Complicated by Polyhydramnios. Ultrasound Obstet Gynecol. 2011 Sep 5. [Medline].

  5. Magann EF, Haas DM, Hill JB, Chauhan SP, Watson EM, Learman LA. Oligohydramnios, Small for Gestational Age and Pregnancy Outcomes: An Analysis Using Precise Measures. Gynecol Obstet Invest. 2011 Oct 26. [Medline].

  6. Kollmann M, Voetsch J, Koidl C, et al. Etiology and perinatal outcome of polyhydramnios. Ultraschall Med. 2014 Aug. 35(4):350-6. [Medline].

  7. Abdel-Fattah SA, Carroll SG, Kyle PM, Soothill PW. Amnioreduction: how much to drain?. Fetal Diagn Ther. 1999 Sep-Oct. 14(5):279-82. [Medline].

  8. Patrelli TS, Gizzo S, Cosmi E, Carpano MG, Di Gangi S, Pedrazzi G, et al. Maternal hydration therapy improves the quantity of amniotic fluid and the pregnancy outcome in third-trimester isolated oligohydramnios: a controlled randomized institutional trial. J Ultrasound Med. 2012 Feb. 31(2):239-44. [Medline].

  9. Cabrol D, Jannet D, Pannier E. Treatment of symptomatic polyhydramnios with indomethacin. Eur J Obstet Gynecol Reprod Biol. 1996 May. 66(1):11-5. [Medline].

  10. Kramer WB, Van den Veyver IB, Kirshon B. Treatment of polyhydramnios with indomethacin. Clin Perinatol. 1994 Sep. 21(3):615-30. [Medline].

  11. Mamopoulos M, Assimakopoulos E, Reece EA, et al. Maternal indomethacin therapy in the treatment of polyhydramnios. Am J Obstet Gynecol. 1990 May. 162(5):1225-9. [Medline].

  12. Desmedt EJ, Henry OA, Beischer NA. Polyhydramnios and associated maternal and fetal complications in singleton pregnancies. Br J Obstet Gynaecol. 1990 Dec. 97(12):1115-22. [Medline].

  13. Biggio JR Jr, Wenstrom KD, Dubard MB, Cliver SP. Hydramnios prediction of adverse perinatal outcome. Obstet Gynecol. 1999 Nov. 94(5 Pt 1):773-7. [Medline].

  14. Brace RA, Resnik R. Dynamics and disorders of amniotic fluid. Creasy RK, Resnik R, eds. Maternal-Fetal Medicine. 4th ed. 1999. 632-43.

  15. Fanaroff AA, Martin RJ. Diseases of the fetus and infant. Neonatal-Perinatal Medicine. 6th ed. 1997. 315-9.

  16. Harrison MR, Golbus MS, Filly RA. Prenatal diagnosis and treatment. The Unborn Patient. 2nd ed. 1990. 139-49.

  17. Hill LM, Breckle R, Thomas ML, Fries JK. Polyhydramnios: ultrasonically detected prevalence and neonatal outcome. Obstet Gynecol. 1987 Jan. 69(1):21-5. [Medline].

  18. Jones KL. Oligohydramnios sequence. Smith's Recognizable Patterns of Human Malformation. 5th ed. 1997.

  19. Kilpatrick SE. Histologic prognostication in soft tissue sarcomas: grading versus subtyping or both? A comprehensive review of the literature with proposed practical guidelines. Ann Diagn Pathol. 1999 Feb. 3(1):48-61. [Medline].

  20. Macri CJ, Schrimmer DB, Leung A, et al. Prophylactic amnioinfusion improves outcome of pregnancy complicated by thick meconium and oligohydramnios. Am J Obstet Gynecol. 1992 Jul. 167(1):117-21. [Medline].

  21. Morales WJ, Talley T. Premature rupture of membranes at 11111Am J Obstet Gynecol</i>. 1993 Feb. 168(2):503-7. [Medline].

  22. Phelan JP, Ahn MO, Smith CV, et al. Amniotic fluid index measurements during pregnancy. J Reprod Med. 1987 Aug. 32(8):601-4. [Medline].

  23. Pitt C, Sanchez-Ramos L, Kaunitz AM, Gaudier F. Prophylactic amnioinfusion for intrapartum oligohydramnios: a meta- analysis of randomized controlled trials. Obstet Gynecol. 2000 Nov. 96(5 Pt 2):861-6. [Medline].

  24. Rib DM, Sherer DM, Woods JR Jr. Maternal and neonatal outcome associated with prolonged premature rupture of membranes below 26 weeks' gestation. Am J Perinatol. 1993 Sep. 10(5):369-73. [Medline].

  25. Schumacher B, Moise KJ Jr. Fetal transfusion for red blood cell alloimmunization in pregnancy. Obstet Gynecol. 1996 Jul. 88(1):137-50. [Medline].

  26. Vergani P, Ghidini A, Locatelli A, et al. Risk factors for pulmonary hypoplasia in second-trimester premature rupture of membranes. Am J Obstet Gynecol. 1994 May. 170(5 Pt 1):1359-64. [Medline].

  27. Xiao ZH, Andre P, Lacaze-Masmonteil T, et al. Outcome of premature infants delivered after prolonged premature rupture of membranes before 25 weeks of gestation. Eur J Obstet Gynecol Reprod Biol. 2000 May. 90(1):67-71. [Medline].

Previous
Next
 
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.