A prospective study of critical methods of amniotic fluid volume assessment

Mayur Rajendra Gandhi


Background: Adequate amniotic fluid volume (AFV) is required for fetal well-being and its assessment is taken as the single most important variable in fetal biophysical scoring system. I have critically evaluated various methods of amniotic fluid volume assessment keeping Amniotic Fluid Index (AFI) as the standard technique of Amniotic Fluid Volume (AFV) assessment.

Methods: This was a prospective study where all patients were assessed for amniotic fluid volume at one sitting first by abdominal palpation followed by ultrasonographic assessment by various methods. Critical analysis of each individual method of amniotic fluid volume assessment was carried out for its sensitivity and specificity with regard to oligohydramnios, polyhydramnios and euamnios keeping AFI as the standard technique of AFV assessment. Effort was made to find out the best possible method of AFV assessment.

Results: Almost all methods are reasonably effective in assessment of normal AFV. For assessment of oligohydraamnios 2cm x 2cm pocket and Maximum Vertical Pocket (MVP) depth (of 2 cm rule) methods are most suitable whereas other methods were found to be inappropriate. For assessment of polyhydramnios with regard to specificity MVP depth (>8cm) is reliable but with regard to sensitivity, subjective assessment and abdominal palpation are more reliable.

Conclusions: When we compare all methods of AFV assessment, AFI and MVP depth (of 2 cm rule) have better correlation. Hence these methods are suggested for AFV studies in current clinical settings.


AFV, AFI, MVP depth

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Chamberlain MB, Manning FA, Morrison I. Ultrasound evaluation of amniotic fluid I. The evaluation of marginal and decreased amniotic fluid volume to perinatal outcome. Am J Obstet Gynecol. 1984;150:245-9.

Doubilet PM, Benson CB. Ultrasound evaluation of amniotic fluid. Ultrasonography in obstetrics and gynecology. Philadelphia; 1994:475-486.

Chamberlain MB, Manning FA, Morrison I. Ultrasound evaluation of amniotic fluid volume II. The relationship of increased amniotic fluid volume to perinatal outcome. Am J Obstet Gynecol. 1984;150:250-4.

Dildy GA, Lira N, Moise KJ, Riddle GD, Deter RL. Amniotic fluid volume assessment: comparison of ultrasonographic estimates versus direct measurements with a dye-dilution technique in human pregnancy. Am J Obstet Gynecol. 1992;167(4):986-94.

Crowley P. Non-quantitative estimation of amniotic fluid volume in suspected prolonged pregnancy. J Perinat Med. 1980;8:249-51.

Tempkin BG, Bizjak PM. Second and third trimester obstetrics Sonography, R.A. Curry, 2nd ed. Elseveir Science. St. Louis;2004:320-355

Manning FA, Platt LD, Sipos L. Antepartum fetal evaluation: development of a fetal biophysical profile. Am J Obstet Gynecol. 1980;136(6):787-95.

Phelan JP, Ahn MO, Smith CV, Rutherford SE, Anderson E. Amniotic fluid index measurements during pregnancy. J Reproduc Med. 1987;32(8):601-4.

Moore TR, Longo J, Leopold GR, Casola G, Gosink BB. The reliability and predictive value of an amniotic fluid scoring system in severe second-trimester oligohydramnios. Obstet Gynecol. 1989;73(5):739-42.

Halperin ME, Fong KW, Zalev AH, Goldsmith CH. Reliability of amniotic fluid volume estimation from ultrasonograms: intra observer and interobserver variation before and after the establishment of criteria. Am J Obstet Gynecol. 1985;153(3):264-7.