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Correlation between Amniotic Fluid Optical Density (AFOD) and functional maturity status of the newborn at caesarean delivery in GDM
... [3] All these three events occurring together at any time from 35+ weeks to 42+ weeks indicate "individual term for each fetus." [4][5][6][7] There are early maturing fetuses which attain completion of functional maturity as early as 35--36 weeks, and there are late maturing fetuses that attain completion of maturity as late as 41--42 weeks. [4][5][6][7] Hypothesis Labors with AFOD value 0.98 ± 0.27 are functionally mature with well-established labor cascades and may respond well to induction. ...
... [4][5][6][7] There are early maturing fetuses which attain completion of functional maturity as early as 35--36 weeks, and there are late maturing fetuses that attain completion of maturity as late as 41--42 weeks. [4][5][6][7] Hypothesis Labors with AFOD value 0.98 ± 0.27 are functionally mature with well-established labor cascades and may respond well to induction. On the other hand, labors with AFOD ≤0.40 are functionally premature with poorly established labor cascades, and may not respond well to induction. ...
... There are early maturing fetuses which attain completion of functional maturity as early as 35--36 weeks, and there are late maturing fetuses that attain completion of maturity as late as 41--42 weeks. [4][5][6][7] Babies born with AFOD value ≤0.40 are functionally premature and develop varying degrees of respiratory distress, irrespective of gestational age and birth weight. ...
Background: Onset of spontaneous labor occurs on completion of fetal functional maturity at amniotic fluid optical density (AFOD) value 0.98 ± 0.27 (Mean ± SD). All three events occurring together at any time from 35 to 42 weeks indicate individual term for each fetus. Babies born with AFOD ≤0.40 are functionally premature and develop varying degrees of respiratory distress syndrome (RDS). In this study, we tested the hypothesis, labors with AFOD 0.98 ± 0.27 are functionally mature with well-established labor cascades and may respond well t o induction. On the other hand, labors with AFOD ≤0.40 are functionally premature with poorly established labor cascades and may not respond well t o induction.
Methods: In this gestational age and parity-matched case control study, cases consisted of 36 uncomplicated singleton laboring women who delivered normally with premature (≤0.40) AFOD values. Controls consisted of 36 similar laboring women who delivered normally with mature AFOD (0.98 ± 0.27) values. Uncentrifuged fresh AF samples collected at amniotomy were used for OD measurement with colorimeter at 650 nm. Women were assigned to groups based on AFOD values. In both groups, labor was induced with vaginal T. Misoprostol 25 mcg 6 hourly up to 4 doses. Labor outcome measures; Bishop score at induction, induction- delivery intervals (IDI), induction failures, number of T. Misoprostol required, presence of fetal distress, RDS, and NICU admission days were recorded in both groups and compared.
Results: Median Bishop scores at induction in cases and controls were 5.0 (IQR 4.25--6), 7.0 (IQR 6--8), respectively. Median IDI in cases and controls were 18 h (IQR 12.25--21.5 h) and 7.0 h (IQR 5--9.5 h), respectively. Number of induction failures in cases and controls were 8 and 0, respectively.
Outcomes of Induction of labor with….
Statistically significant differences observed in all these outcomes between groups (P = 0.00) favoring inductions with mature AFOD.
Conclusion: Labor induction with mature AFOD value was successful in all women with shorter IDI and with better perinatal outcomes.
... Babies born with AFOD value ≤ 0.40 are functionally premature and develop varying degrees of respiratory distress, irrespective of gestational age, and birth weight. [2][3][4][5] Raising levels of amniotic fluid lecithin during the third trimester induces progressive and rapid detachment of vernix from the fetal skin surface. The detached vernix clumps get mixed with amniotic fluid, resulting in a rapid surge like a change of color in liquor before the onset of spontaneous labor. ...
... There are early maturing fetuses that attain completion of functional maturity as early as 35-36 weeks, and there are late maturing fetuses that attain completion of maturity as late as 41-42 weeks. [2][3][4][5] This concept of "individualized term for each fetus" is having a very significant impact on clinical obstetrics. ...
Background: Onset of spontaneous labor occurs on completion of fetal functional maturity at amniotic fluid optical density (AFOD) 0.98 ± 0.27 (mean ± SD). All three events occurring together at any time from 35 weeks to 42 weeks indicate the individualized term for each fetus. No failures of induction of labor were reported when labors induced at AFOD 0.98 ± 0.27. As AFOD estimation needs invasive amniocentesis, we tried to induce women with liquor with mature AFOD by observing the sonographic appearances of fore-water by transvaginal sonography.
Methods: In this comparative study, three groups of gestational age and parity matched uncomplicated singleton term pregnant women, underwent fore-water trans-vaginal sonography before induction of labor with Foley's catheter. Sonographic images were divided into three grades based on floating particle densities. Each group consisted of 20 women with each grade of sonographic images. Uncentrifuged fresh AF samples collected at amniotomy were used for AFOD measurement with colorimeter at 650 nm in all groups. After Foley's expulsion, labor was augmented with vaginal misoprostol. The mean AFOD values, Foley's insertion expulsion intervals, Foley's insertion delivery intervals (FIDI), T misoprostol required, and neonatal respiratory distress were recorded in each group and compared.
Results: In groups 1, 2, and 3, the mean AFOD was found to be 0.29 ± 0.09, 0.68 ± 0.14, and 1.15 ± 0.20, respectively. Mean Foley's insertion expulsion intervals were 10.57 ± 3.76 h, 5.83 ± 2.24 h, and 4.08 ± 0.86 h, respectively. Mean FIDI were 20.00 ± 6.20 h, 11.22 ± 4.20 h, and 8.95 ± 2.98 h, respectively. The mean numbers of T misoprostol required in each group was 3 ± 1, 2 ± 1, and 2 ± 1, respectively. Significant differences were observed in all outcomes between groups (P < 0.05) favouring inductions with Grade 3 sonographic images.
Conclusion: Labor induction with Grade 3 sonographic images of fore-water was successful in all women with shorter FIDI, and with better perinatal outcomes.
... are functionally mature, skin was pleased brown in colour with little vernix, none of them had respiratory distress. 30 Amniotic fluid optical density <0.4 developed respiratory distress. 31,32 In our study, mean difference in AFOD among the cases with and without respiratory distress was found to be 0.4±0.1 and 1.2±0.1, ...
Background: Respiratory distress is the common cause of neonatal morbidity and mortality. Babies born even at 40 weeks of gestation developed respiratory distress. The maturity of newborn is independent of gestational age and birth weight of newborn. In this study amniotic fluid optical density (AFOD) is correlated with the functional maturity of newborn.Methods: In this study, hundred singleton pregnant women who underwent first trimester scan and crown rump length estimation, and who were on spontaneous labor were selected for this observational study. Under aseptic precautions AF samples were collected while doing amniotomy with 2 ml disposable syringe, also collected during caesarean section after careful hysterotomy from the bulging membranes. Amniotic fluid optical density studied with spectrometer at 650 nm. Birth weights were recorded for all the babies. Babies are also looked for the respiratory distress, NICU admission.Results: In this study, respiratory distress was reported in 28% of newborns whereas 72% of newborns did not have distress. In the present study, 27% of newborns were admitted in NICU where as 73% of the newborns were on mother’s side following delivery. Babies with AFOD 0.98±0.27 were functionally mature, skin was pleased brown in colour with little vernix, none of them had respiratory distress. Amniotic fluid optical density <0.4 developed respiratory distress.Conclusions: Amniotic fluid optical density is a simple method to assess the functional maturity of newborn.
Background:S.Ramet.al reported: Onset of spontaneous labor occurs at completion of fetal functional maturity at AFOD value of 0.98±0.27 (at 650nm). All these events together occurring at any time from 35+wks to 42+wks indicateindividual term for each fetus 1, 2 .Preterm labors with AFOD 0.98±0.27 are mature and cannot be stopped by any means, as labor cascades are already established. Babies born with AFOD <0.40 arefunctionally premature 1, 2 , and we expected thesepremature laborswouldrespond well for tocolysis and other methods for continuation of pregnancies as labor cascades are not fully established. Methods:In thiscase series study, 22 singleton pregnant women who were inpreterm labor (PTL),and who underwent CRL gestational age estimations, 5 of them PTL with membrane rupture and17 without membrane rupture were included. USG guided amniocentesis was performed as per the ACOG guidelines, and AFOD estimations were done for fresh uncentrifuzed samples. Antenatal corticosteroids, low dose Isoxsuprine Hcl rapid infusion tocolysis, and weekly 17-alphahydroxy progesterone caproate were given. After successful tocolysis and continuation of pregnancies, AFOD estimations were repeated when women presented with labor pains again before 37w+6days. Women were allowed to deliver if mature or near mature AFOD values were observed. AFOD estimations were also done at spontaneous labor or at caesarean sections after 38wks. Babies were observed for functional maturity in terms of color of skin, adherence of vernix, and development of RDS. Results were presented in two tables and analyzed. Results:In non-membrane rupture group (N=17), pregnancies could be continued for 1 to 7 wks. In membrane rupture group, in N=2/5 women leak could be stopped and pregnancies could be continued for 3 to 6 wks. Except one, in both groups all babies could attain mature or near mature AFOD values irrespective of GA and birth weight,noRDS was observed, and all babies survived. Conclusion:WithAFOD guided PTL management coupled with low dose Isoxsuprine Hcl rapid infusion tocolysis, pregnancies could be continued to completion of fetal functional maturity in 21/22 women with good neonatal outcome.
Background: Therapies to stabilize clinical manifestations and prolong pregnancies to attain fetal viability in preeclampsia do not exist 1. Antiangiogenic factor, Soluble fms-like tyrosine kinase1 (sFlt-1) induces preeclampsia-like phenotype in experimental models 2 , and circulates at high levels in preeclampsia. Extracorporeal removal of circulating sFlt-1 by Dextran-sulfate apheresis reduces proteinuria and stabilizes blood pressure without apparent adverse effects on fetus and mother 1 .Serum, Urine, and fractional excretion of sFlt-1 are much higher among severe preeclamptic women compared to mild pre-eclamptic controls 3. Consuming plenty oral fluids and producing urine output more than 2500ml/24hrs, may significantly reduce clinical symptoms, and may help to continue pregnancies to viability, as enhanced sFlt1 renal excretion is possible. Methods: In this case control study, twenty women with very preterm (<34wks) preeclampsia with hydration therapy was compared with gestational age matched twenty controls without intervention. Cases were advised to consume plenty oral fluids and produce a targeted urine output more than 2500ml/24hrs. Anti-hypertensive drugs, Nifidepin, T. Labetalol, and weekly Inj. Hydroxy progesterone were given. Mean arterial pressure, urine albumin dipstick, edema grade, serum sodium, and potassium were recorded at different gestational ages in both groups and compared. The number of weeks that pregnancy continued, birth-weights, RDS, NICU admission days, indications for termination of pregnancies, and take home babies, were recorded in both groups and compared. Amniotic Fluid Optical Density estimations (AFOD) were done at the time of termination of pregnancies in cases. Results: Mean daily urine output was 3692±989ml in cases. Statistically significant reduction in blood pressure, albuminuria, edema, was observed in cases (P=0.000, 0.000, 0.000). Continuation of pregnancy in cases was 7.51±5.22wks, and in controls it was 1.38±1.18wks (P=0.000). Significant decrease in RDS, NICU admission days (P=0.000, 0.001), and increase in birth-weights and take home babies (P=0.000, 0.041) were observed in cases. No significant difference was observed in serum sodium, and potassium levels between two groups (P=0.201, 0.072). The Mean AFOD at termination of pregnancies in casas was 0.86±0.37 Conclusion: Oral hydration therapy with urine output 3962±989ml/24hrs helps to prolong very preterm pre-eclamptic pregnancies to term with good perinatal outcome.
Objective: To establish the correlation between the
Amniotic fluid (AF) Optical density (OD) at the
onset of spontaneous labor and the functional
maturity, gestational age and birth weight of the
newborn.
Methods: Uncentrifuged fresh amniotic fluid
samples from 360 singleton pregnancies were
collected during artificial rupture of membranes or
amniotomy at LSCS after onset of labor for AFOD
estimation at 650 nm .
Results: The mean AFOD at spontaneous labor
was found to be 0.98±0.27 (n=360). The study
population was divided into 7 different groups
according to gestational age (GA) (35 1/7 -36 wks,
36 1/7-37wks, 37 1/7-38 wks, 38 1/7-39 wks, 39
1/7-40 wks , 401/7-41wks, and above 41 wks of
GA respectively). In different GA groups, the mean
AFOD at spontaneous labor ranged from
0.50±0.13 to 1.03±0.24. Between any two groups
among 2 to 7 (i.e. after 36 wks GA) when cases of
respiratory distress syndrome (RDS) was
excluded, there is no essential change in mean
AFOD values (range 0.85 to 1.03). The results
were same after adjusting for birth weights. All the
babies delivered at AFOD value of mean ± SD
0.98 ±0.27 (0.40 to 1.55 CI 95 %) ,were fully
functionally mature and did not develop RDS.
Babies born with AFOD < 0.40 (n=8) had varying
degrees of RDS with birth weights ranging from
2300 to 3000 gms. Also they had more vernix on
their body than the non RDS babies The mean
birth weights progressively increased from group 1
to 7.
Synopsis: Spontaneous normal labor takes
place with complete fetal functional maturity at an
optimum AFOD value of 0.90 irrespective of the
GA and birth weight in our study population. The
correlation of AFOD with functional maturity
supports the concept of individual term
We report a case of pregnancy at full term and transabdominal ultrasonography (USG) revealed minute amniotic fluid particles prior to onset of spontaneous labor. Amniotic Fluid Optical Density (AFOD) estimation for fetal lung maturity was done. AFOD was 0.43 in uncentifuged and 0.14 in centrifuged samples at 650 nm. USG at onset of labor detected amniotic fluid particles of 3-4 mm size corresponding to AFOD of 1.40 (uncentrifuged sample) at ARM. The rapid increase in the size of the echogenic amniotic fluid particles simultaneously with optical density may be able to serve as an index of physiological process that contributes to the onset of labor.
India today is being recognized as the diabetic capital of the world. Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance of variable severity with onset or first diagnosed during pregnancy [1]. It is a serious medical complication of pregnancy, which affects 1.1–14.3 % of pregnant women depending on the ethnic and clinical characteristics of the population and the diagnostic test employed [2]. The increasing incidence of GDM is because of, apart from other risk factors, rise in maternal age and maternal body mass index. Prevalence rates are found to be higher in black Hispanic, native American and Asian women compared to white women. In India, 79 million people are expected to have diabetes mellitus by the year 2030 (1). The prevalence of GDM in India varies from 9.9 % in rural population to 17.8 % in urban areas (2) [3]. The National Family Health Survey (NFHS) III—2005–2006 of India reported an increasing prevalence, 14.8 %, of overweight women aged 15–49 years (ranging from 28.9 % in urban areas to 8.6 % in rural areas) compared to 10.6 % in 1998–99 (3). [4] GDM has adverse outcomes of pregnancy including preeclampsia, caesarean section rates (which varied from 30 to 40 %), perinatal mortality (2-fold increased), birth defects, macrosomia (3-fold increased), shoulder dystocia, metabolic complications in neonates and morbidity associated with subsequent childhood obesity. Furthermore, the recurrence risk with future pregnancies has been reported as high as 68 % [4], and 26 % [5] risk of developing type two diabetes at 15 years of follow up. Therefore, the diagnosis of GDM offers a unique opportunity in identifying individuals who will be benefited by early therapeutic intervention with diet and exercise, thus normalizing the weight to delay or even possibly prevent the onset of diabetes. In 2005, Crowther et al. [6] reported in their randomized controlled trial that treatment of GDM reduced serious perinatal morbidity (combined endpoint of death, shoulder dystocia, bone fracture and nerve palsy) and the incidence of large-for-gestational-age infants. In 2009, Landon et al. [7] reported that treatment of women with mild GDM showed significant reduction in large-for-gestational-age infants, shoulder dystocia, caesarean section, preeclampsia or gestational hypertension and less maternal weight gain. Therefore, due to its high incidence, major impact on pregnancy outcome and therapeutic approaches, a universal, instead of a selective, screening has been recommended.
One of the most important preventive measures in obstetrics is the individual evaluation of the most appropriate time to terminate a pregnancy. The value of amnioscopy used as the method for evaluation of fetal maturity has been ascertained. It has been observed that the delivery of a mature newborn in most cases starts spontaneously at the moment we recognize milky amniotic fluid by amnioscopy. These infants possess mostly a reduced quantity of vernix on the skin and do not manifest any adaptation disturbances in the perinatal period. By amnioscopy the quality of the pure amniotic fluid as well as the quantity of vernix caseosa are determined. Our studies have confirmed the well known observation that with increasing gestational age the quantity of vernix on the fetal skin is diminishing indicating the increased chance for postmaturity. After term, significantly more infants are born without vernix (Vernix O) than before term (P<0.001), and significantly less infants were entirely covered with vernix (P<0.001). 200 women were examined by amnioscopy during the last days before spontaneous delivery of a mature infant. Milky amniotic fluid with nuances was observed in 91% during the last four days before delivery, while 9 and more days before delivery clear amniotic fluid was always found. A distinct relation exists between the appearance of milky amniotic fluid at amnioscopy, and the diminishing quantity of vernix on the fetus after delivery. Of 200 women in whom milky amniotic fluid was observed by amnioscopy during 0 to 4 days before delivery, only 5.5% of the infants were entirely covered with vernix (Vernix III), while in all other cases the amount of vernix was decreased. Of 100 women in whom clear amniotic fluid was observed 0 to 4 days before delivery, Vernix III was observed after delivery in 51% of cases. The difference is statistically significant (P<0.001). In prematures, Vernix III was observed after the birth in 84% of cases. Dynamics of changes in amniotic fluid and vernix changes on the fetus is shown: Approximately one week before delivery of a mature infant, the vernix begins to flake off the skin and the consequence is the appearance of milky amniotic fluid with particles of vernix. The milky amniotic fluid at amnioscopy was the only indication for 250 inductions which were performed within 46 days (from 26 days before till 20 days after the calculated term). All infants were mature and had no trouble in the perinatal period. The appearance of milky (mature) amniotic fluid indicates the maturity of the fetus and gives an indication for the termination of the pregnancy if delivery does not occur spontaneously within a few days. Estimation of vernix on the fetus at delivery is presently the most simple method for the evaluation of infant maturity. The newborns partly covered with vernix (Vernix I and II) are mature and do not show any adaptation disturbances after delivery. The infants, born without vernix (Vernix 0) are also mature, but here some cases of postmaturity can be found. Some infants who are entirely covered with vernix (Vernix III) at delivery have some adaptation disturbances during the perinatal period.
This study was aimed to correlate echogenic amniotic fluid particle size (AFPS) in late third trimester to fetal lung maturity and amniotic fluid optical density (AFOD) at labor. AFPS were measured with specified criteria by real time transabdominal USG (3.5MHz) while Amniotic Fluid Index (AFI) was measured during routine antenatal visits. The criteria for AFPS score which are taken into account are the amniotic fluid particle size, number and distribution. Serial AFPS measurements were done till onset of labor. AFPS was correlated to AFOD value at spontaneous labor in 123 women. Uncentrifuged fresh amniotic fluid samples were obtained during ARM/amniotomy and used for AFOD estimation at 650 nm. The mean AFPS and AFOD at onset of labor was found to be 5.14 ± 0.69 mm (3.67 – 6.7 CI 95%) and 1.03 ± 0.31 (0.35 -1.69 CI 95%) respectively in 116 women who delivered normal babies devoid of respiratory distress syndrome (RDS). Serial AFPS measurements showed a definite AFOD surge after a value in the region of 3.8 mm which is obtained culminating in onset of Labor. 28 women (24.1%) had dense clusters of free floating particles across the vertical pool in amniotic fluid with mean AFPS and AFOD of 5.6 ± 0.68 mm and 1.12 ± 0.21 respectively. In 123 women, AFPS < 3.8 mm had sensitivity of 85.74% and positive predictive value of 66.67% in predicting RDS. AFPS serves as a sonological marker for fetal lung maturity and labor. The range of AFOD values can be measured in terms of AFPS (r =0.6, F = 69.8, β= + 0.23, p < 0.001). Serial AFPS estimation predicts fetal maturity and onset of labor.
Fetal pulmonary maturity is generally determined by analyzing amniotic fluid for surfactants. This task is accomplished by lipid extraction of the fluid and resolution, identification and quantitation of the isolated lipids with thin-layer chromatography. These methods are lengthy, cumbersome and often not available on demand. A quick, simple, reliable and economical test therefore would be highly desirable. We have been able to correlate an optical density (OD) reading of amniotic fluid at 650 nm greater than or equal to 0.15 with the absence of hyaline membrane disease (HMD). For 428 fluids in which an OD reading of greater than or equal to 0.15 was found and delivery occurred within 48 hours, HMD was present in only two infants. The accuracy of the test was 99.53% , with a false-positive rate of 0.47%. With the use of this simple and accurate test one can satisfy the requirement of an on-demand test to determine fetal pulmonary maturity.
The maturation of the fetal lungs, that is to say the adequate production of surfactant in the fetal alveoli, as it is well known reaches to its end about the 35.-36th week of gestation. Even more closely to the date of delivery, about the 37.-38th week of gestation, the maturation of the fetal skin takes place, so to say the detachment of the Vernix caseosa from the fetal skin into the amniotic fluid. The above mentioned means that the children with "mature skin" should have mature lungs too, so that those children have about nothing to fear from the RDS. That can be proved by the comparison of the values which were measured in 38 cases of the L/S Ratio (as a criterion of the lung-maturity), to those of the turbidity of the amniotic fluid and average quantities of the keratinocytes of the amniotic fluid cell population (as a criterion of the skin-maturity); that observation becomes stronger with the comparison of all those values to a Vernix-Score, which can be completed after delivery.
The concentrations of surfactant obtained from dynamic measurement of surface tension of amniotic fluid as well as from amniotomy were determined for 26 births, all close to full term between 38th and 41st weeks of pregnancy). The compliance of the newborns' respiratory systems were postnatally established by means of the occlusion method. No pulmonary functionality was accurately identified from amniotic fluid in 92.3 per cent of all cases, and respiratory compliance was in good agreement with clinical symptoms in 25 of 26 newborns. All four cases of RDS were recorded from the group in which labour had been induced by amniotomy, with three of the four newborns weighing more than 2,500 g. These results are likely to show that RDS can develop even in infants born very close to full term and that the risk of RDS following induced labour is higher with significance than it would be following spontaneous onset of labour.
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Amniotic fluid optical density (AFOD) surge coincides with the onset of spontaneous term labor. Paper presented at 55 th AICOG-2012
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http://www.youtube.com/watch?v=-sjTQ0OX_RA&feature=g-upl