Amniotic fluid is a clear and transparent liquid in which the fetus lives. It is principally made up of water (96.4%), mineral salts and organic substances [1] [2]. Its volume increases from 20 ml at 7 weeks of gestation, to 980 ml at 34 weeks and then drops to 540 ml at 42 weeks. Its reabsorption is mainly by fetal swallowing and absorption through the amniotic membrane [2]. Two main abnormalities of amniotic fluid are volume and colour changes. Colour abnormality could be blood or meconium stained (MSAF) [2]. Meconium is the first stool of the fetus or neonate and its emission occurs between 24 and 48 hours of extra uterine life [3] [4] [5]. Certain pathological conditions can cause its emission before delivery, thus staining the amniotic fluid green. MSAF is a common finding in obstetric and neonatal practice with occurrence varying from 5% to 24.6% of deliveries [6]. Its incidence increases with gestational age, up to 30% at 40 weeks and 50% at 42 weeks [7] [8].

Although the exact cause of this MSAF is unclear, fetal distress, cord accidents and maternal hypertension have been identified as potential risk factors [9] [10]. Intrauterine emission of meconium has both fetal and neonatal consequences as well as maternal risks [5]. Studies done in India and Pakistan showed higher proportions of caesarean delivery, abnormal fetal heart rhythm, meconium inhalation syndrome (MIS), low Apgar score (< 7) at the fifth minute, neonatal sepsis and death in cases of MSAF [11] [12] [13]. In the USA and United Kingdoms, guidelines have been set for the management of cases with MSAF in order to reduce these complications [14] [15] [16]. These guidelines include continuous surveillance and amnioinfusion in cases of thick MSAF. These have led to a significant reduction in caesarean section rates [17] [18] [19]. With an extensive literature search, there is lack of studies assessing maternal and neonatal outcomes in case of MSAF in Cameroon. Therefore, this study aimed at determining the fetal, neonatal and maternal complications associated with MSAF in order to improve its management.

The aim of this study was to determine the maternal and fetal outcomes in case of meconium stained amniotic fluid observed during labour of term singleton pregnancy in cephalic presentation. We found that the prevalence of MSAF was 11.15%. MSAF was associated with a significant risk of caesarean delivery and prolonged labor. Also, MSAF was associated with the following fetal and neonatal complications; fetal heart rate abnormalities, low Apgar score at the 5^th minute, need for neonatal resuscitation, neonatal asphyxia and neonatal infection. Meconium aspiration syndrome (MAS) was found in 2.34% of MSAF cases. Perinatal mortality was 2.34% and all cases of death occurred in the thick MSAF group.

We found a prevalence of MSAF of 11.15%. This finding is within the 5% to 24.6% interval stated in the literature [6] , although higher than the 8.3% reported by Patil K.et al. in 2006 in India [18]. The higher prevalence observed in the current study could be explained by the fact that the study was conducted in two tertiary level hospitals in the capital city that receive referrals from the peripheral health facilities. Thick MSAF represented 52.1% and light MSAF represented 47.9%. This concurs with findings from other low-and-middle income countries; 53% in Guinea [24] and 64.3% in India [18]. The high frequency of thick MSAF could be due to the fact that evaluating amniotic fluid as lightly stained is very subjective and as such, the prevalence may greatly vary from one author to the other [9].

The mean gestational age was greater in the group with MSAF compared to the CAF group (39.7 vs 39.2 weeks: p = 0.0001). Moreover, the incidence of MSAF was 60.9% in cases with gestational age greater than 40 weeks. This positive correlation between advanced gestational age and the prevalence of MSAF concurs with previous observations made by Meis et al. [7] and Millar et al. [8] who found that the prevalence of MSAF could be up to 50% at 42 weeks of gestation.

Similar to studies done by by Erum et al. [11] and Salma et al. [12] , we found MSAF to be associated with some maternal morbidities; a two-fold increase in caesarean delivery and a three-fold increase in chorioamnionitis and prolonged labour. We may attribute the high incidence of caesarean deliveries in this study to inadequate intrapartum fetal heart monitoring. As such, the presence of meconium in the amniotic fluid was an alarming sign of fetal distress and treated accordingly by emergency caesarean section.

After stratifying maternal morbidities according to the consistency of the MSAF, it was noted that thick MSAF compared to light MSAF and clear amniotic fluid (CAF) respectively increased the risk of caesarean delivery by 1.67 and 2.48. Similar results were found by Aparna et al. [9] and Nirmala et al. [13] in India where the risk of caesarean delivery was multiplied by 3 in case of thick MSAF. Likewise, all the cases of puerperal infections were found in the group with thick MSAF. Thick MSAF increased maternal morbidities significantly in cases of MSAF.

Fetal morbidities were significantly higher in case of MSAF. These included non-reassuring fetal heart rhythm (p < 10⁻⁴), low Apgar scores at first and fifth minutes (p < 10⁻⁴ and p < 10⁻² respectively), neonatal infection (NNI) and neonatal asphyxia (NNA) (p < 10⁻³ and p < 10⁻¹ respectively). Similar results were obtained in India [9] and Guinea [25] where fetal heart rhythm anomaly was 5 times higher in case of MSAF. The various proportions of low Apgar scores (<7) at the first minute were 3.8%, 23.9% and 36.9% in case of CAF, MSAF and thick MSAF respectively. In a similar order, low Apgar scores at the fifth minute were respectively 4.2%, 12.2% and 20.7% in case of CAF, MSAF and thick MSAF respectively. These differences in proportions were significantly higher in the group with thick MSAF both at the first and fifth minutes {1^st minute (RR = 9.83; p < 10⁻⁴) and 5^th minute (RR = 4.90; p < 10⁻²)}. Patil et al. obtained similar results with low Apgar scores in 19% of cases of MSAF [18]. Nirmala et al. [13] found low Apgar scores in 16% of cases with MSAF and only in the first minute. The persistent difference in Apgar scores both at 1^st and 5^th minutes and in case of CAF observed in our series could suggest insufficient neonatal resuscitation. There was an overall drop in the proportions of low Apgar scores from the 1st to the 5^th minute. NNI (RR = 5.6; p = 10⁻⁴) and NNA (RR = 2.71; p < 10⁻¹) were significantly more common in cases with MSAF. Noteworthy, the relative risk values are higher for thick MSAF compared to CAF; RR = 6.61 for NNI and RR = 4.39 for NNA. The observed value in the current study is higher than those recently obtained by Kumari et al. [26] and by Rajlaxmi et al. [27]. This high association of NNI and MSAF in our series could be explained by high proportions of prolonged premature rupture of membranes and resuscitation technics in the group with MSAF (p = 0.0047 and p = 0.0026 respectively). Lastly, perinatal mortality was 4.69% in the group with MSAF versus 0% in the group with CAF; and all the cases were thick MSAF. Similar rates were obtained by Salma et al. [12] with risk of death multiplied by 2 in case of MSAF. Patil et al. [18] noted a mortality of 4%, all in the group with thick MSAF.

Our results should be interpreted within the study’s limitations. These include the sole use of fetal heart rhythm to diagnose acute fetal distress and the short term postpartum follow up period of 72 hours (coinciding with the hospital discharge of participants). As such, some complications could be missed because of this early exit from the hospital. However, based on well followed-up patients, we have used a cohort design to provide a contribution of level II scientific evidence to the scarcity on the outcomes of maternal and fetal outcomes in case of meconium stained amniotic fluid observed during labour of term singleton pregnancy in the sub-Saharan African region. These findings may guide obstetricians and midwives in making informed clinical decisions in their therapeutic strategies MSAF observed during labour in these resource-constrained environments.

MSAF observed during labour of term singleton pregnancies in cephalic presentations was associated with maternal and fetal complications. Its detection during labor warrants rigorous intra partum and postpartum monitoring for a timely diagnosis and management of these complications.

The authors report no declaration of interest.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Dohbit, J.S., Mah, E.M., Essiben, F., Nzene, E.M., Meka, E.U.N., Foumane, P., Tochie, J.N., Kadia, B.M., Elong, F.A. and Nana, P.N. (2018) Maternal and Fetal Outcomes Following Labour at Term in Singleton Pregnancies with Meconium-Stained Amniotic Fluid: A Prospective Cohort Study. Open Journal of Obstetrics and Gynecology, 8, 790-802. https://doi.org/10.4236/ojog.2018.89082

Patient identification:

File N˚: _________ Date: ____ /____/____

Contact adresss: ___________________ Age (years): _______

Marital Status: maried □; single □; divorced ,; widow ,

Level of education: not formal,; primary ,; secondary ,; higher ,

Occupation: housewife , student , civil servant , private worker , independant ,

Monthly revenu (Fcfa):

<25,000 , [25,000 - 50,000[ , [50,000 - 100,000[ , ≥ 100,000 ,

Last mentrual period:__/__/__ Expected day of confinment: _/_/_ Gestational age (weeks-days) ____________________

Presenting complaint: labour pains □; vaginal bleeding,; lost of liquoir□; others____________________

History of pregnancy:

No of antenatal care visits: ___; VIH serology: negative , positive ,

Level of haemoglobin: <10 g/dl ,; ≥ 10g/dl ,

Pathologies in pregnanacy: anaemia□; malaria □; urinary infection ,; diabetes ,; Hypertension , others ___________________________________

Gravida ___ Para__________________; No of past cesarean sections: ____

Medical History: None □; Hypertension: Yes ,/No ,; diabetes: Yes ,/No ,

Cardiopathy: Yes □/No □ others ____________________

Monitoring of labour (partograph)

Mode of rupture of membranes: Spontanous , Artificial ,

Delay of rupture of membranes: Premature Rupture: Yes ,/No ,

Prolonged Rupture: Yes ,/No ,

Nature of liquoir: Clear ,/Meconial , If meconial, colour: green ,; yellow ,; purulent ,

Consistency of liquoir: light , thick ,; Odour of liquoir: foul smelling , not foul smelling ,

Moment of detection of MSAF: before onset of labour ,; latent phase ,; active phase ,; expulsion phase ,; intra operative ,

MSAF noticed immediately at membrane rupture ,/Initial clear liquoir followed by MSAF ,

Fetal heart rate anomaly during labour: Yes ,/No ,

If Yes: Tachycardia , Bradycardia , Deceleration ,

If deceleration: type I , type II , type III ,

Maternal fever (temp > 37.8): Yes ,/No ,; Maternal tachycardia (>100): Yes ,/No ,

Uterine pain on palpation: Yes ,/No , Clinical chorioamnionitis: Yes ,/No ,

Mode of delivery:

Normal vaginal delivery □;

Instrumental □ (Indication: fetal distress , cephalopelvic disproportion ,; fatigue , others___________)

Cesaerian section □ (Indication: fetal distress □; cephalopelvic disproportion □; others ____________________________)

Duration of labour: Normal , Prolonged ,

If prolonged: 1^st stage , duration____ 2^nd stage , duration____ 3^rd stage , duration____

Placenta: weight(g) __________; meconial stained: Yes □ /No □

Calcifications: Yes ,/No ,; other anomalies________________________

Umbilical Cord: meconial stained: Yes □ /No □; cord knot: Yes □ /No □

Cord round neck: Yes ,/No ,; cord prolapse: Yes ,/No , other anomalies _________________________

State of newborn:

Gender: Male , Female ,; Weight(g) _______________

APGAR: 1^st min____/10; 5^th min____/10

Resuscitation: Yes ,/No ,; if yes: Duration____________________ min, Method_________________

Respiratory distress: Yes ,/No ,; Neonatal Asphyxia: Yes ,/No ,

Meconium inhalation syndrome: Yes □,/No ,; Neonatal Infection: Yes ,/No,

Neonatal unit admission: Yes ,/No ,;

Neonatal death: Yes ,/No ,

Follow-up of the mother and newborn

NNI: Neonatal infection, NNA: Neonatal asphyxia, RD: Respiratory distress, MIS: Meconium inhalation syndrome.