A Comparative Study on Fetomaternal Outcome in Patients with Meconium-stained Amniotic Fluid vs Clear Amniotic Fluid

Rezumat

shortly after birth with radiographic evidences of aspiration pneumonitis and meconium stained amniotic fluid 5 .MAS is associated with fetal acidemia that is abnormally increased Pco2 values rather than pure acidemia 5 .MAS is 100% more likely to occur in meconium-stained amniotic fluid than in clear amniotic fluid.

METHODOLOGY
This was a randomized, observational, prospective study and was conducted in the Department of Obstetrics and Gynaecology of Dhiraj Hospital, Vadodara, Gujarat, India.Sample size: 240 patients Duration: 1 st October 2022 to 30 th May 2023.Data was collected and then analysed by SPSS 21.

INCLUSION CRITERIA
• Patients giving consent for study • Full term singleton pregnancy.(GA: 37 weeks to 40 weeks) • Cephalic presentation.
• Spontaneous onset of labour • Spontaneous or artificial rupture of membranes with meconium stained or clear liquor.• No high-risk conditions (obstetrical or medical)

EXCLUSION CRITERIA
• Patients not consenting for study • Gestational age <37weeks and >40weeks • Previous uterine scar for caesarean or else.
• Any pelvic deformity or vaginal obstruction to normal delivery.
• Patients not willing to participate Cases and control group were those with meconium-stained amniotic fluid and with clear amniotic fluid respectively.Two groups of meconium-stained cases were clinically classified according to type of staining-thin (54 cases-lightly stained amniotic fluid, yellow or greenish in colour) and thick (66 cases-dark green/black stained amniotic fluid usually thick and tenacious).Consent for participation in the study was

INTRODUCTION
The fetus in utero has various protective mechanisms of which, one of them is amniotic fluid.The amniotic fluid is essential for the normal development of the fetus.It is essential for normal lung growth and fetal swallowing permits gastrointestinal tract development.Amniotic fluid also creates physical space for fetal movement which is required for neuro-musculo-skeletal development.It guards the umbilical cord from compression and protects fetus from trauma.Amniotic fluid also has bacteriostatic properties 1 .The amniotic fluid volume increases gradually from 30ml at 10weeks to approximately 800ml by mid third trimester.In early pregnancy, it is colourless and at term becomes pale straw coloured.Abnormal colours of amniotic fluid indicate different pathologies.
The amount of meconium passed out due to underlying pathology, determines the severity of neonatal morbidity.A small amount changes the colour of liquor to light green and warrants timely delivery if risk is to be minimized.Thick meconium suggests severe hypoxia and of longer duration, that will require neonatal resuscitation and intensive care.
Meconium is sterile, thick, blackish green, odourless material, formed by accumulation of debris in the fetal intestine.Passage of meconium into amniotic fluid before delivery or during stages of labour can be due to 3 theories: 1.In response to hypoxia or asphyxia as a sign of fetal compromise.2. Gastrointestinal tract maturation under neural control 3. Due to vagal stimulation from transient umbilical cord entrapment with resultant increased bowel peristalsis 2 The risk factors for meconium-stained amniotic fluid can be both maternal and fetal.The maternal factors are hypertension, gestational diabetes mellitus, pre-eclampsia, post term pregnancy, maternal drug abuse (tobacco, cocaine), placental insufficiency. 3 The fetal factors are oligohydramnios, intrauterine growth retardation with poor biophysical profile. 4he most common complication of meconium-stained liquor being meconium aspiration syndrome and birth asphyxia.Meconium aspiration syndrome is defined as respiratory distress that develops Neha NIMBARK et al.
A Comparative Study on Fetomaternal Outcome in Patients with Meconium-stained Amniotic Fluid vs Clear Amniotic Fluid taken from the patients.All the information was noted in a printed performa.General and obstetrical examination of mother during labour was done.The labour was monitored, the mode of delivery, Apgar scores at one and five minutes, birth weight, resuscitation of baby, neonatal intensive care (NICU) admissions, birth asphyxia, meconium aspiration syndrome (MAS), early neonatal deaths were noted.Use of any medications was recorded.Clinical fetal monitoring i.e., fetal heart rate was noted throughout the progress of labour.All babies of both groups were followed up to 1st week of neonatal life.
In present study bradycardia was when fetal heart rate below 100 bpm and tachycardia was when fetal heart rate above 160 bpm.Fetal distress included FHR abnormalities (bradycardia, tachycardia, significant variable deceleration.Loss of beat-to-beat variability, fetal arrhythmias), decreased or absent fetal movements and Non-reactive NST.Babies were considered not asphyxiated and in good condition when the Apgar score was 7 or higher, moderately asphyxiated when the score was 4 to 6, and severely asphyxiated when the score was less than 4.

STATISTICAL ANALYSIS
The statistical analysis was done using SPSS Software.All the qualitative data were presented as .frequencyand percentages and were compared using Fisher's test or Chi-square test.P-Value of < 0.05 was considered as significant.

OBSERVATIONS AND RESULTS
During the study period, 120 cases who had meconium staining of amniotic fluid, gave the incidence of 6.5%.(Total 1830 deliveries) Among these 120 cases, 66 cases had thick meconium and 54 cases had thin meconium.In study group maximum numbers of cases (54.54%) were. in the age group of 2l-25 years .andmean age group was 23.6 years.In the control group also maximum number of cases (57.85%), were in the same age group and mean age was 22.98 years.Approximately 62.79% had gestational ages of 39-40 weeks, was higher in study group.ascompared to controls (57.02), but difference was not statistically significant.Unbooked cases were more in study group as compare to in control group.Out of unbooked cases 27.72% were of thick meconium stained (Table 1).Among the MSL group 4 cases of thick MSL babies were grossly asphyxiated and had APGAR score of 1-3 at 1 minute and score of 4-6 at 5 min.Among the MSL group 95% babies had APGAR score 7-10 at 1 min and in the control group it was 98%.Among control group 2 babies were grossly asphyxiated and Apgar score 1-3 at 1 min but the score was 4-6 at 5min.Total number of babies asphyxiated were 22 in MSL group whereas in control group it was 9.The APGAR score Table 5. Fetal outcome at 1 min was statistically significant between thick and thin MSL; MSL and control group, whereas no difference was seen in APGAR scores at 5min.In the study group, the APGAR score less than 7 at 1 min was 5% whereas in control group it was 1.66%.The APGAR score of less than 7 was observed at 5 min in 3.33% of MSL group.Neonatal morbidity was significantly associated with MSL group and was 38% in the study group and 16% in the control group.The morbidity was more in the thick MSL group 52% than that of the thin MSL group.Admission to NICU was more in cases (18%) than that of control group (7%), it is due to MAS in study group.In the present study the perinatal deaths were 4% in the MSL group.The fetal outcome was adversely affected by the MSL in our study (P val-ue<0.01)

DISCUSSION
In the present study, 120 cases of MSL group were studied in a period of 5 months to evaluate the effect of MSL during labour on fetal outcome, an equal number of cases with clear liquor were taken as control.54 cases had thin MSL and 66 cases had thick MSL noted at the time of spontaneous or artificial rupture of membranes.The incidence of MSL group was 7.7%.The mean gestational age was higher (39.82 weeks).MSL does not appear to be related with the volume of amniotic fluid in.term pregnancies, and its presence increases the risk of caesarean delivery for fetal distress independent of amniotic fluid volume 6 .
There is significantly higher incidence of risk factors in.MSL group that was similar to the study of Rashid etal. 7The incidence of caesarean section was highest in thick meconium group, that was 59.70% and out of total MSL cases 48%.delivered by caesarean section whereas in control group it was 12%.In comparison to thin MSL group, incidence of cesarean section was near about double in thick MSL group.In the study group, overall percentage of caesarean section was increased due to fetal distress indicated by MSL and abnormal NST.Saunders et al., also reported that caesarean sections were performed twice as frequently in subjects with meconium-stained amniotic fluid.This higher rate may be due to lack of facilities such as, foetal scalp pH monitoring and tracings of foetal electronic monitoring 8 .Fujikura et al, observed that the incidence of meconium staining was significantly more with increased birth weight more than 3 kgs . [9]But in our study, there was no difference between MSG and control group in respect of birth weight.In both groups about same number of babies are of > 3 kgs birth weight but mean birth weight was high in study group 2.92 kg where as in control group2.88kgs.27% cases of study group were unbooked.incomparison to control (19%).This study showed that a majority of cases with MSAF were unbooked which is in accordance with the study done by Bhide et al,. 10 The commonest associated abnormal fetal heart rate pattern observed in this study was bradycardia (36%) in.MSG whereas tachycardia was 13%.Babies complicated.by still birth and asphyxia in bradycardia group more (29.54%)than the babies delivered having normal fetal heart rate pattern (9.52%).Non-reactive NST was two times more in study group compared to control group and more in thick group 51% compared to thin group 20%, which was consistent with Rosario 11 Majority incidence of birth asphyxia among the babies born with MSAF was higher compared to the control cases with clear liquor.MAS was present in 8.5% of cases in the MSAF group in our study.In contrast to our study, the incidence of MAS was lower in the study by Tolu et al. (6.3%) 12 Dani et al found that there is a positive correlation between the severity of meconium staining and thickness and the outcomes of term infants born after a non-eventful pregnancy. 13MSAF is associated with higher rate of caesarean delivery, instrumental delivery, NICU admission rate, fetal distress, low birth weight and neonatal death. 14Identification of the high-risk factors is important, and timely referral of the patients to centers with proper neonatal care facilities with mechanical ventilators reduces neonatal morbidity and mortality. 15

CONCLUSION
Meconium-stained liquor can lead to caesarean sections, meconium aspiration syndrome, birth asphyxia and increase NICU admissions, hence concerns both obstetricians and neonatologists equally.The study proved that meconium staining of amniotic fluid affects the maternal and fetal outcome adversely.Hence in presence of thick meconium needs vigilant monitoring, prompt obstetric intervention and good neonatal care in order to prevent or minimize meconium-stained liquor related adverse outcomes.

Table 1 .
Prevalence of msaf in relation to maternal age, gestational age, booking status

Table 2 .
Mode of delivery

Table 4 .
Correlation of intrapartum.fetal heart rate and condition of baby at birth in msl group and control group The condition of the babies in thick MSL group was worse than the control group (P-value<0.01)(table 4)