今日の臨床サポート

羊水過多、過少

著者: 坂井 昌人 東京ベイ・浦安市川医療センター 産婦人科

監修: 金山尚裕 静岡医療科学専門大学校

著者校正/監修レビュー済:2017/04/27

概要・推奨   

ポイント:
  1. 羊水過多・過少の診断は超音波断層法で行うのがよい。羊水量の測定は(amniotic fluid index、AFI)、または、羊水ポケット(maximum vertical pocket、MVP)の計測によるのが一般的。正常値は8cm≦AFI≦20cm,2cm≦MVP<8cmである。
  1. 羊水過多も羊水過少も原因、発症時期により治療方針や児の予後に大きな違いがあるため、過多・過少が診断されたら、まず、原因の検索を行う。
 
羊水過多の原因の評価:
  1. 羊水過多の6割は原因不明という。羊水過多の大部分を占める軽度~中等度過多では自然軽快もあり得る。原因不明の軽度~中等度羊水過多には、胎児が大きめだが妊娠糖尿病ではない例が多く、それらの児の多くは予後良好である。しかし原因不明とされる羊水過多には、原因が超音波検査等では診断できないものが含まれるため、児転帰は不良のことがある。
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となり
閲覧にはご契
閲覧にはご契約が必要と
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります
  1. 閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要となります。閲覧にはご契約が必要
薬剤監修について:
オーダー内の薬剤用量は日本医科大学付属病院 薬剤部 部長 伊勢雄也 以下、林太祐、渡邉裕次、井ノ口岳洋、梅田将光による疑義照会のプロセスを実施、疑義照会の対象については著者の方による再確認を実施しております。
※薬剤中分類、用法、同効薬、診療報酬は、エルゼビアが独自に作成した薬剤情報であり、
著者により作成された情報ではありません。
尚、用法は添付文書より、同効薬は、薬剤師監修のもとで作成しております。
※薬剤情報の(適外/適内/⽤量内/⽤量外/㊜)等の表記は、エルゼビアジャパン編集部によって記載日時にレセプトチェックソフトなどで確認し作成しております。ただし、これらの記載は、実際の保険適用の査定において保険適用及び保険適用外と判断されることを保証するものではありません。また、検査薬、輸液、血液製剤、全身麻酔薬、抗癌剤等の薬剤は保険適用の記載の一部を割愛させていただいています。
(詳細はこちらを参照)
著者のCOI(Conflicts of Interest)開示:
坂井 昌人 : 特に申告事項無し[2021年]
監修:金山尚裕 : 特に申告事項無し[2021年]

病態・疫学・診察

疾患(疫学・病態)のまとめ  
  1. 羊水量は産生(胎児尿がほとんど)と吸収(主に胎児燕下→消化管吸収、または破水により失う)のバランスにより決まる。
  1. 羊水過多・過少は産生から吸収までのどこかの異常を表している。母体・胎児・付属物のいずれかの異常を示唆している。
  1. 羊水過多では、軽度のもの、程度が軽快していくものは原因不明で児予後が良好なことが多いが、高度なものほど原因は判明しやすく、児の予後不良な可能性が上昇する。
  1. 羊水過少では、一般に発症が早期であるほど児予後が不良である(胎児異常、肺低形成など)。
  1. 羊水過多では子宮増大による早産や破水のリスク、過少では子宮収縮時の臍帯圧迫、早期からの過少では児の肺低形成などのリスクがある。
問診、診察のポイント  
  1. 羊水量の異常、すなわち過多・過少は、定期的な妊婦健診を行うなかで疑診とされ、診断基準に当てはめて診断されることが多い。妊婦は妊婦健診という定期的な受診をしているため診断の遅れを起こしにくくしている。しかし、妊娠中期までは健診は4週ごとなので、急性発症の場合はやや診断が遅れることもある。

これより先の閲覧には個人契約のトライアルまたはお申込みが必要です。

最新のエビデンスに基づいた二次文献データベース「今日の臨床サポート」。
常時アップデートされており、最新のエビデンスを各分野のエキスパートが豊富な図表や処方・検査例を交えて分かりやすく解説。日常臨床で遭遇するほぼ全ての症状・疾患から薬剤・検査情報まで瞬時に検索可能です。

まずは15日間無料トライアル
本サイトの知的財産権は全てエルゼビアまたはコンテンツのライセンサーに帰属します。私的利用及び別途規定されている場合を除き、本サイトの利用はいかなる許諾を与えるものでもありません。 本サイト、そのコンテンツ、製品およびサービスのご利用は、お客様ご自身の責任において行ってください。本サイトの利用に基づくいかなる損害についても、エルゼビアは一切の責任及び賠償義務を負いません。 また、本サイトの利用を以て、本サイト利用者は、本サイトの利用に基づき第三者に生じるいかなる損害についても、エルゼビアを免責することに合意したことになります。  本サイトを利用される医学・医療提供者は、独自の臨床的判断を行使するべきです。本サイト利用者の判断においてリスクを正当なものとして受け入れる用意がない限り、コンテンツにおいて提案されている検査または処置がなされるべきではありません。 医学の急速な進歩に鑑み、エルゼビアは、本サイト利用者が診断方法および投与量について、独自に検証を行うことを推奨いたします。

文献 

著者: J P Phelan, C V Smith, P Broussard, M Small
雑誌名: J Reprod Med. 1987 Jul;32(7):540-2.
Abstract/Text An ultrasound approach was developed to identify normal amniotic fluid volume. The uterine cavity was divided into four quadrants. With the use of linear-array, real-time B-scanning, the vertical diameter of the largest pocket in each quadrant was measured. The sum of these four quadrants was used to provide a single number for the amniotic fluid volume and termed the amniotic fluid index. This approach is simple, requires little time and gives a semiquantitative estimate of amniotic fluid volume. Based on our observations, the normal amniotic fluid index in term gestation is 12.9 +/- 4.6 cm. Evaluation of the relationship between amniotic fluid volume and fetal outcome is under investigation.

PMID 3305930  J Reprod Med. 1987 Jul;32(7):540-2.
著者: P F Chamberlain, F A Manning, I Morrison, C R Harman, I R Lange
雑誌名: Am J Obstet Gynecol. 1984 Oct 1;150(3):250-4.
Abstract/Text Qualitative amniotic fluid volume determination is a routine part of fetal biophysical profile score testing. The relationship between polyhydramnios and poor perinatal outcome has been previously documented. We have undertaken a retrospective chart review which relates qualitative amniotic fluid volume as determined at the time of last biophysical profile score assessment to perinatal outcome in 7562 referred high-risk obstetric patients. Gross and corrected perinatal mortality in association with normal qualitative amniotic fluid volume ranged from 4.65/1000 and 1.97/1000, respectively, to 32.9/1000 and 4.12/1000 in association with increased qualitative amniotic fluid volume, respectively. The incidences of major congenital anomaly and fetal macrosomia were significantly related to qualitative amniotic fluid volume.

PMID 6385714  Am J Obstet Gynecol. 1984 Oct 1;150(3):250-4.
著者: Everett F Magann, Dorota A Doherty, Suneet P Chauhan, Friedrich W J Busch, Federico Mecacci, John C Morrison
雑誌名: Am J Obstet Gynecol. 2004 Jan;190(1):164-9.
Abstract/Text OBJECTIVE: This study was undertaken to determine whether the amniotic fluid index (AFI) and single deepest pocket percentiles can reliably identify a dye-determined amniotic fluid volume.
STUDY DESIGN: Ultrasound measurements and dye-determined volumes were prospectively collected. Oligohydramnios predictors included AFI and single deepest pocket below the 3rd and 5th percentiles, and hydramnios predictors were based on AFI and single deepest pocket above the 95th and 97th percentiles.
RESULTS: Two hundred ninety-one women with singleton pregnancies participated, including 75 pregnancies (26%) with oligohydramnios and 31 pregnancies (10%) with hydramnios. The predictive ability of the AFI and single deepest pocket indices (<3rd and 5th percentiles) to identify oligohydramnios was between 11% and 27% and to identify hydramnios (>95th and 97th percentiles) ranged between 33% and 46%. The best prediction was for normal fluid volume with an accuracy of 83% to 94%.
CONCLUSION: Amniotic fluid indices perform best for the identifying normal AF volumes, whereas the identification of oligohydramnios or hydramnios is poor.

PMID 14749654  Am J Obstet Gynecol. 2004 Jan;190(1):164-9.
著者: D E Carlson, L D Platt, A L Medearis, J Horenstein
雑誌名: Obstet Gynecol. 1990 Jun;75(6):989-93.
Abstract/Text Little has been written regarding the ultrasonographic quantification of polyhydramnios or its subsequent management. Therefore, we designed this study to define polyhydramnios using the amniotic fluid index of greater than 2 SDs above the mean for late second- to third-trimester pregnancies, or 24 cm or greater. One hundred twelve nondiabetic women referred to Women's Hospital, Los Angeles County/University of Southern California Medical Center with the descriptive diagnosis of polyhydramnios made by experienced ultrasonographers were included in the study. There was poor correlation between these descriptions and fetal outcome. Twenty-six were qualitatively described as having severe, 29 as moderate, and 57 as mild polyhydramnios. Forty-nine of the 112 patients met our definition of significant polyhydramnios by having an amniotic fluid index of 24 cm or more. This particular definition allowed the inclusion of all fetuses with serious structural defects and/or death. Seven patients had an amniotic fluid index less than 24 cm, but with the traditional quantitative definition of one pocket of 8 cm or more; none of these patients had poor fetal outcome. These data appear to suggest that the use of descriptive definitions of polyhydramnios or a single fluid pocket of 8 cm or greater should be discarded in favor of using an amniotic fluid index of 24 cm or more. Once the diagnosis of polyhydramnios is made, the patient should have a detailed sonographic evaluation, be offered cytogenetic studies, and have antepartum surveillance.

PMID 2188185  Obstet Gynecol. 1990 Jun;75(6):989-93.
著者: R Sohaey, D A Nyberg, G K Sickler, M A Williams
雑誌名: Radiology. 1994 Feb;190(2):393-6. doi: 10.1148/radiology.190.2.8284386.
Abstract/Text PURPOSE: To determine the relationship between idiopathic polyhydramnios and fetal macrosomia in the absence of maternal diabetes.
MATERIALS AND METHODS: Idiopathic polyhydramnios was studied with ultrasound (US) in 99 consecutive normal fetuses of nondiabetic women. Birth weights and estimated fetal weights were compared with those of postnatal and prenatal control groups, respectively.
RESULTS: The mean birth weight for the study (polyhydramnios) group was 3,771 g +/- 572 (standard deviation) compared with 3,476 g +/- 444 for the postnatal control group (P < .001). Birth weights in the 90th percentile or greater occurred in 28.2% of the study group versus 9.3% of the postnatal control group (P < .001) with a relative risk of 3.0 and a 95% confidence interval of 1.9, 4.9. The mean percentile of estimated fetal weight obtained with US was also significantly greater for the study group (79.3 +/- 23.7) than for the prenatal control group (51.5 +/- 32.7) (P < .001).
CONCLUSION: Idiopathic polyhydramnios is associated with large-for-gestational-age fetuses and macrosomia independent of maternal diabetes.

PMID 8284386  Radiology. 1994 Feb;190(2):393-6. doi: 10.1148/radiolog・・・
著者: Desirée M J Dorleijn, Titia E Cohen-Overbeek, Floris Groenendaal, Hein W Bruinse, Philip Stoutenbeek
雑誌名: J Matern Fetal Neonatal Med. 2009 Apr;22(4):315-20. doi: 10.1080/14767050802531870.
Abstract/Text OBJECTIVE: Our objective was to investigate the outcome of neonates with idiopathic polyhydramnios in the first year after birth.
METHODS: All patients diagnosed in the Erasmus Medical Centre Rotterdam and the University Medical Centre Utrecht between January 2000 and April 2005 with idiopathic polyhydramnios were studied. The outcome variables included mode of delivery, pre-term delivery, birth weight, macrosomia, large-for-gestational-age (weight > p90), neonatal or infant mortality and infant morbidity at 1 year after delivery. These were related to antenatal findings, including the onset of polyhydramnios and ultrasonographic evidence of macrosomia (estimated fetal weight > p90).
RESULTS: Polyhydramnios was diagnosed at a mean gestational age (+/- s.d.) of 31.0 +/- 4.9 weeks. The mean gestational age at birth (+/- s.d.) was 37.9 +/- 3.7 weeks. Macrosomia at birth was present in 25.3% (22/88). Sixty-three of 88 infants were in good health 1 year after birth; 20 infants had an abnormality and 5 children had died. Macrosomia and detection of polyhydramnios in the third trimester was associated significantly with a good outcome.
CONCLUSION: In neonates with idiopathic polyhydramnios, abnormalities were detected during the first year of life in 28.4%. Detection of polyhydramnios in the second trimester and low or normal birth weight are risk factors for associated abnormalities.

PMID 19085623  J Matern Fetal Neonatal Med. 2009 Apr;22(4):315-20. doi・・・
著者: T D Shipp, B Bromley, S Pauker, F D Frigoletto, B R Benacerraf
雑誌名: Ultrasound Obstet Gynecol. 1996 Feb;7(2):108-13. doi: 10.1046/j.1469-0705.1996.07020108.x.
Abstract/Text We evaluated the significance of severe oligohydramnios, or anhydramnios, in the second and third trimesters, by determining the range of etiologies as well as the differences in fetal and neonatal outcome. All prenatal ultrasound results on pregnancies found to have severe oligohydramnios over a 7.5-year period at 13-42 weeks' gestation were retrospectively collected. Follow-up results were obtained from review of medical records, autopsies and pathology reports. A total of 250 singleton pregnancies met the criteria of having severe oligohydramnios. A bimodal distribution in gestational age at diagnosis was seen, with more cases diagnosed at 13-21 weeks and at 34-42 weeks. Fetal abnormalities were present in 50.7% of those diagnosed with severe oligohydramnios in the second trimester and in 22.1% of those in the third trimester. There were 10.2% and 85.3% survivors when severe oligohydramnios was diagnosed in the second and third trimesters, respectively. The rate of aneuploidy was at least 4.4% for the entire singleton population. A bimodal distribution of pregnancies presenting with severe oligohydramnios represents two different naturally occurring populations in terms of both etiology and prognosis.

PMID 8776235  Ultrasound Obstet Gynecol. 1996 Feb;7(2):108-13. doi: 1・・・
著者: R B Gold, G L Goyert, D B Schwartz, M I Evans, L A Seabolt
雑誌名: Obstet Gynecol. 1989 Nov;74(5):745-7.
Abstract/Text During a 32-month period, 603 genetic amniocenteses were performed in our institution, and seven patients (1.2%) experienced fluid leakage within 24 hours of the procedure. All seven patients were hospitalized for strict bed rest and expectant management. Cessation of amniotic fluid leakage and reaccumulation of normal amniotic fluid occurred within 7 days in all cases. Six patients were delivered at term of appropriately grown infants without complication. One patient experienced an intrauterine death at 25 weeks' gestation (6 weeks after the occurrence of fluid leakage secondary to genetic amniocentesis). Although limited by the small number of patients, our experience suggests the following: 1) Appropriate respect for potential complications of genetic amniocentesis is still warranted; 2) expectant management of patients who experience membrane rupture after genetic amniocentesis may be associated with a good perinatal outcome; and 3) membrane rupture after genetic amniocentesis may represent a fundamentally different etiologic entity than spontaneous rupture of the membranes in the second trimester not associated with genetic amniocentesis.

PMID 2812651  Obstet Gynecol. 1989 Nov;74(5):745-7.
著者: W B Kramer, I B Van den Veyver, B Kirshon
雑誌名: Clin Perinatol. 1994 Sep;21(3):615-30.
Abstract/Text Polyhydramnios detected in a pregnancy should always be investigated thoroughly. We believe chromosomal abnormalities should be excluded, but that determination need not delay therapy. Indomethacin has been shown to reduce amniotic fluid volume in certain cases, but a strict monitoring schedule should be followed whenever it is administered. At our institution, we are investigating the effect on the fetus of newer, more selective prostaglandin synthetase inhibitors that should have beneficial effects similar to indomethacin, but be devoid of its unwanted side effects.

PMID 7982337  Clin Perinatol. 1994 Sep;21(3):615-30.
著者: K J Moise
雑誌名: Clin Obstet Gynecol. 1997 Jun;40(2):266-79.
Abstract/Text
PMID 9199839  Clin Obstet Gynecol. 1997 Jun;40(2):266-79.
著者: William D Fraser, Justus Hofmeyr, Roberto Lede, Gilles Faron, Sophie Alexander, François Goffinet, Arne Ohlsson, Céline Goulet, Lucile Turcot-Lemay, Walter Prendiville, Sylvie Marcoux, Louise Laperrière, Chantal Roy, Stavros Petrou, Hai-Rong Xu, Bin Wei, Amnioinfusion Trial Group
雑誌名: N Engl J Med. 2005 Sep 1;353(9):909-17. doi: 10.1056/NEJMoa050223.
Abstract/Text BACKGROUND: It is uncertain whether amnioinfusion (infusion of saline into the amniotic cavity) in women who have thick meconium staining of the amniotic fluid reduces the risk of perinatal death, moderate or severe meconium aspiration syndrome, or both.
METHODS: We performed a multicenter trial in which 1998 pregnant women in labor at 36 or more weeks of gestation who had thick meconium staining of the amniotic fluid were stratified according to the presence or absence of variable decelerations in fetal heart rate and then randomly assigned to amnioinfusion or to standard care. The composite primary outcome measure was perinatal death, moderate or severe meconium aspiration syndrome, or both.
RESULTS: Perinatal death, moderate or severe meconium aspiration syndrome, or both occurred in 44 infants (4.5 percent) of women in the amnioinfusion group and 35 infants (3.5 percent) of women in the control group (relative risk, 1.26; 95 percent confidence interval, 0.82 to 1.95). Five perinatal deaths occurred in the amnioinfusion group and five in the control group. The rate of cesarean delivery was 31.8 percent in the amnioinfusion group and 29.0 percent in the control group (relative risk, 1.10; 95 percent confidence interval, 0.96 to 1.25).
CONCLUSIONS: For women in labor who have thick meconium staining of the amniotic fluid, amnioinfusion did not reduce the risk of moderate or severe meconium aspiration syndrome, perinatal death, or other major maternal or neonatal disorders.

Copyright 2005 Massachusetts Medical Society.
PMID 16135835  N Engl J Med. 2005 Sep 1;353(9):909-17. doi: 10.1056/NE・・・
著者: A Golan, I Wolman, J Sagi, I Yovel, M P David
雑誌名: Gynecol Obstet Invest. 1994;37(1):18-20.
Abstract/Text One hundred and thirteen cases of polyhydramnios diagnosed by repeated ultrasonic examinations in singleton pregnancies were divided into two groups according to the trend of change in the amniotic fluid volume between the first and the second ultrasonic examination. Group A patients (65 cases) showed an increase or no change in amniotic fluid volume, and in group B (48 cases) a reduction in amniotic fluid volume to mild polyhydramnios or to normal amniotic fluid volume was observed. A significantly increased rate (p < 0.05) of maternal complications such as diabetes mellitus, pregnancy-induced hypertension, urinary tract infections, premature rupture of membranes and premature delivery was observed in group A. More abdominal deliveries and an increased rate of fetal anomalies, fetal abnormal presentations, intrauterine fetal death and neonatal death also occurred in this group. Group B patients, most of whom were idiopathic, showed a very favorable outcome.

PMID 8125402  Gynecol Obstet Invest. 1994;37(1):18-20.
著者: J M Morris, K Thompson, J Smithey, G Gaffney, I Cooke, P Chamberlain, P Hope, D Altman, I Z MacKenzie
雑誌名: BJOG. 2003 Nov;110(11):989-94.
Abstract/Text OBJECTIVE: To determine whether a single ultrasound scan at or beyond 40 weeks of gestation to detect a single deepest pool of amniotic fluid <2 cm and amniotic fluid index (AFI) <5 cm is clinically useful in the prediction of subsequent adverse pregnancy outcome.
DESIGN: A prospective double blind cohort study.
SETTING: A university teaching hospital delivering approximately 6000 women annually.
POPULATION: One thousand and five hundred and eighty-four pregnant women at or beyond 40 weeks of gestation.
METHODS: Ultrasound assessment of liquor to detect the single deepest pool of amniotic fluid and derive the AFI at or after 40 weeks of gestation.
MAIN OUTCOME MEASURES: Perinatal death, meconium aspiration, birth asphyxia, intervention in labour for fetal distress, a cord arterial pH <7 and admission to the neonatal unit.
RESULTS: An AFI <5 cm but not a single deepest pool <2 cm was significantly associated with birth asphyxia or meconium aspiration. An AFI <5 cm was also significantly associated with caesarean section for fetal distress in labour, a cord arterial pH <7 at delivery and low Apgar scores. Despite there being a statistically significant association with adverse outcomes the sensitivity of AFI was low at 28.6%, 12% and 11.5% for major adverse outcome, fetal distress in labour or admission to the neonatal unit, respectively.
CONCLUSIONS: The AFI is superior to a measure of the single deepest pool as an assessment of the fetus at or after 40 weeks but has a poor sensitivity for adverse pregnancy outcome. Routine use is likely to lead to increased obstetric intervention without improvement in perinatal outcomes.

PMID 14592583  BJOG. 2003 Nov;110(11):989-94.

ページ上部に戻る

戻る

さらなるご利用にはご登録が必要です。

こちらよりご契約または優待日間無料トライアルお申込みをお願いします。

(※トライアルご登録は1名様につき、一度となります)


ご契約の場合はご招待された方だけのご優待特典があります。

以下の優待コードを入力いただくと、

契約期間が通常12ヵ月のところ、14ヵ月ご利用いただけます。

優待コード: (利用期限:まで)

ご契約はこちらから