Related Experiment Videos
Amniotic fluid index measurements during pregnancy
J P Phelan1, M O Ahn, C V Smith
1Department of Obstetrics and Gynecology, University of Southern California School of Medicine.
The Journal of Reproductive Medicine
|August 1, 1987
Summary
The amniotic fluid index (AFI) increases until 26 weeks gestation, then stabilizes around 16.2 cm until 38 weeks. Serial AFI measurements are valuable for monitoring fetal status during pregnancy.
Area of Science:
- Obstetrics and Gynecology
- Maternal-Fetal Medicine
- Diagnostic Ultrasound
Background:
- Amniotic fluid volume assessment is crucial for antepartum fetal surveillance.
- The amniotic fluid index (AFI), using the four-quadrant technique, is a common method.
- Previous studies focused on AFI and pregnancy outcomes, but not its changes throughout gestation.
Purpose of the Study:
- To investigate the changes in amniotic fluid index (AFI) throughout pregnancy, from 11 to 43 weeks' gestation.
- To establish normal AFI ranges across different gestational periods.
- To evaluate the utility of serial AFI measurements for fetal status assessment.
Main Methods:
- Prospective study involving 197 patients with clinically and sonographically confirmed "good dates".
- Amniotic fluid index (AFI) measured using the four-quadrant technique (sum of largest vertical pockets).
- Real-time linear array B-scan ultrasound utilized for all assessments.
Main Results:
- Amniotic fluid index (AFI) progressively increased from 11 to 26 weeks' gestation.
- From 26 weeks to term, the mean AFI remained stable at approximately 16.2 +/- 5.3 cm.
- A gradual decline in AFI was observed after 38 weeks' gestation.
Conclusions:
- The study provides normative data for AFI changes throughout pregnancy.
- Serial AFI measurements appear to be an effective method for assessing fetal well-being.
- Findings corroborate previously established normal amniotic fluid volumes.