Deepest vertical amniotic fluid pocket at term. Normal values and clinical application.

Area of Science:

• Obstetrics and Gynecology
• Fetal Medicine
• Maternal-Fetal Medicine

Background:

• Amniotic fluid volume is crucial for fetal well-being.
• The deepest vertical pocket (DVP) is a key ultrasound measurement.
• Understanding DVP's relationship with birth weight aids in managing high-risk pregnancies.

Purpose of the Study:

• To establish normal deepest vertical pocket (DVP) values in term pregnancies.
• To investigate the correlation between DVP and birth weight (BW).
• To assess DVP's utility in identifying large for gestational age (LGA) and small for gestational age (SGA) infants.

Main Methods:

• Ultrasound assessment of DVP in 231 term patients (37-42 weeks) with normal amniotic fluid index (AFI).
• Comparison of DVP with actual birth weight (BW), including LGA (> 4,000 g) and SGA (< 2,500 g) categories.
• Statistical analysis using linear regression models to determine correlations.

Main Results:

• Mean DVP was 4.5 cm, showing no significant variation with gestational age.
• A positive linear correlation was found between DVP and BW.
• Higher DVP was significantly associated with LGA infants (5.2 vs. 4.3 cm, P < .003).
• A DVP > 6 cm increased the relative risk of an LGA infant, particularly with maternal diabetes (RR 15.8).
• No significant DVP difference was observed for SGA infants.

Conclusions:

• Elevated DVP is a predictor of delivering a large for gestational age infant.
• The association between higher DVP and LGA infants is more pronounced in pregnancies complicated by maternal diabetes.
• DVP measurement can be a valuable tool in antenatal assessment of fetal growth.