Amniotic fluid lamellar body concentration as a marker of fetal lung maturity at term elective caesarean delivery.
BACKGROUND
Caesarean birth, without prior labour, is associated with an increased risk of neonatal respiratory morbidity among term infants. The concentration of lamellar bodies in amniotic fluid reflects pulmonary surfactant production and release, and is thus used in preterm populations as a marker of fetal lung maturity. Whether amniotic fluid lamellar body concentration (AFLBC) may correlate with risk factors for term respiratory distress has not previously been evaluated.


OBJECTIVE
To determine the relationship between AFLBC and risk factors for respiratory distress following term caesarean birth.


METHODS
The AFLBC of 249 women at the time of term caesarean birth was examined for an association with gestational age, gender, presentation and neonatal respiratory distress requiring special care nursery (SCN) admission.


RESULTS
There was a significant increase in AFLBC with gestation. When compared with caesarean deliveries performed during the 37th week of gestation, there was a 50%, 54% and 56% increase in lamellar body concentrations (LBCs) taken during the 38th, 39th and 40th week of gestation respectively (P < 0.05 for all). Female fetuses had a 16% higher LBC than males (P < 0.05). An LBC <100 x 10(9) mL(-1) was associated with increased risk of admission to the SCN with respiratory distress (RR = 5.6; 1.2-26.5, P < 0.05).


CONCLUSIONS
Known risk factors for term respiratory distress are reflected in the AFLBC. A significant relationship exists between AFLBC and respiratory morbidity following term caesarean birth. However, the low prevalence of this condition limits the clinical role of AFLBC as a predictive test for term respiratory morbidity.
Walker
Susan P
SP
Department of Obstetrics and Gynaecology, University of Melbourne, Victoria, Australia. spwalker@unimelb.edu.au
Chow
Yvonne Y C
YY
Ugoni
Antoni M
AM
Holberton
James R
JR
Smith
Carole L
CL
Permezel
Michael J
MJ
D000653:Amniotic Fluid / Q000737:chemistry*; D015415:Biomarkers / Q000737:chemistry; D002585:Cesarean Section; D017558:Elective Surgical Procedures; D005260:Female; D005325:Fetal Organ Maturity; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008168:Lung / Q000196:embryology* / Q000378:metabolism*; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011663:Pulmonary Surfactants / Q000737:chemistry*; D012127:Respiratory Distress Syndrome, Newborn
D015415:Biomarkers; D011663:Pulmonary Surfactants