Type of fetal malformation in a referral clinic in Beirut Lebanon and compare to the literature by Kariman Ghazal* in Open Access Journal of Biogeneric Science and Research
Abstract
Background: Ultrasonography has been shown to be an important tool for detecting congenital malformation. The objective of this study was to assess the feasibility and value of first trimester ultrasonography in the detection of fetal anomaly and how the information from ultrasound can influence the outcome of pregnancy.
Methods: A retrospective observational study was conducted between December 2018 and December 2020 on singleton pregnant women visiting the antenatal private clinic. All patients were screened for congenital anomalies by ultrasound scan during the first trimester. Demographics, maternal characteristics, and complications as well as malformation prevalence and types were recorded.
Results: A total of 159 women visited the antenatal clinic during the study period. The mean age was 28.15±5.53 years. The rate of consanguinity was 8.8%. Almost 99% of the women consumed folic acid during pregnancy while 45.3% took folic acid before pregnancy. Regarding symptoms complications during pregnancy, 93.7% of the women had vomiting, and around 20% had gestational diabetes and hypertension. The first trimester ultrasound of 31 women (19.5%) showed congenital anomalies of their fetus. Of the 31, 9 (29.0%) had malformation in the central nervous system (CNS) and brain, 7 (22.6%) had cardiac malformation, 2 (6.5%) had gastrointestinal anomaly, renal malformation, and skeletal defect, while 12 (38.7%) had other types of anomaly such as Down Syndrome and anomaly in the umbilical cord and limbs. As for pregnancy outcome, of the 31 who had malformation, 10 (32.3%) aborted, 1 (3.2%) had IUFD, 9 (29.0%) delivered through NVD, and 11 (35.5%) had CS. Of the 20 who delivered by NVD or CS, 8 (40.0%) of the neonates died directly after delivery or after few days.
Conclusion: First trimester ultrasound is an important tool for early detection of congenital anomalies. This would assist in initiating timely and multidisciplinary interventions.
Keywords: Pelvic ultrasound first trimestre malformations.
Introduction
The prevalence of congenital anomalies prenatal and posnatal ranges between 1.8% and 3% in different regions of the world [1-4] . Ultrasonography has been shown to be an important tool for detecting congenital malformation. The common practice is to perform an ultrasound evaluation of fetal anatomy during the second trimester (at 18 to 22 weeks’ gestation) [5]. The number of ultrasound scans varies depending on medical practice, the availability of qualified providers and equipment, in addition to the incurred costs [5].
Although some organ systems develop after the first trimester; yet, the importance of first-trimester ultrasound is being emphasized since it has the utility for confirming fetal viability, determining gestational age, detecting multiple gestation, identifying ectopic and cesarean scar pregnancies, evaluating the risk of chromosomal disorders and fetal anomalies, as well as assessing nuchal translunary [6-8]. There is an association between increased nuchal translucency and chromosomal abnormalities, specifically trisomy 21, and structural anomalies, such as cardiac abnormalities [9, 10].
Several fetal anomalies develop before 12 weeks of gestation. Hence, appropriate visualization of the fetus at this stage allows early detection of congenital anomalies [11]. The ultrasound detection rates for major structural anomalies in the first trimester was reported to be more than 40% [12]. Early detection of structural anomalies would assist the parents and physicians in planning multidisciplinary interventions during pregnancy or the early postpartum period, which could decrease neonatal and infant morbidity and mortality [7, 13].
Given that first trimester ultrasound is not just a screening tool for chromosomal anomalies, but also a method to identify anatomic anomalies, the aim of this study was to assess the feasibility and value of first trimester ultrasonography in the detection of fetal anomaly and how the information from ultrasound can influence the outcome of pregnancy.
Material and Methods
A retrospective observational study was conducted between December 2018 and December 2020 on pregnant women visiting the antenatal private clinic. Women with singleton pregnancies whom gestational age was established using the last menstrual period date and was confirmed through first trimester ultrasound were included in the study. Exclusion criteria were poor fetal visualization because of technical factors and multiple gestation.
Data collected included patients’ demographic and maternal characteristics such as age, body mass index (BMI), detailed obstetric history (gravida, parity, and abortions), consanguinity, smoking, and folic acid consumption. Moreover, maternal complications, illness (gestational diabetes and hypertension), and delivery characteristics were noted. In addition, neonatal characteristics and malformation were recorded.
All patients were screened for congenital anomalies by ultrasound scan during the first trimester as part of routine antenatal care. For the purposes of this study, first trimester included all examinations before 14 weeks of gestation. First trimester anomaly scan was performed by SAMSUNG R7 Expert ultrasound machine using 2.5 – 3.5 MHz probe.. The scan included demonstration of fetal location (intrauterine or ectopic), spontaneous fetal movements, and fetal organs. For gestational age calculation, fetal growth measurements such as crown-rump length, biparietal diameter, head and abdominal circumference, and femur length were done. Nuchal translucency was also measured. Fetal head was examined for shape, bilateral ventricular size, and choroid plexus. Fronto-maxillary facial angle, nasal bone, and ductus venosus Doppler were done. Examination also included abdominal organs, spine, limbs, fetal heart rate and cardiac chambers. Fetal echocardiography was done if there was any sign of cardiac anomaly. Umbilical cord and position of placenta were inspected. Neonates were examined by pediatricians after delivery.
The ultrasound findings were correlated with the results, chromosome analysis, further ultrasound studies performed in the second and third trimesters, fetal echocardiography, and results of postnatal follow-up when available. Termination with dilation and curettage prevented detailed pathologic examination in some cases.
Data Analysis
Data were analyzed using the Statistical Package for Social Sciences (SPSS) version 24. Descriptive analysis was performed. Categorical variables were presented as number and percent and were compared using Chi-square test or Fisher’s exact test. Continuous variables were presented as mean ± standard deviation and were compared using t-test. P-value less than 0.05 was considered statistically significant.
Results
1A total of 159 women visited the antenatal clinic during the study period. The demographic and maternal characteristics are presented in Table 1. The mean age was 28.15±5.53 years. Around 53% of the parturients had BMI ≥35 kg/m2 and 32.7% had one previous abortion. The rate of consanguinity was 8.8%. About 7% had thyroid diseases before pregnancy. Almost 99% of the women consumed folic acid during pregnancy while 45.3.0% took folic acid before pregnancy (Table 1).
Table 1: Demographic and maternal characteristics.
Table 2: Maternal complications and delivery.
Table 3: Neonatal characteristics and malformation.
Table 4: Outcome of pregnancy of the 31 women who had first trimester ultrasound malformation.
Table 5: Relation between maternal characteristics and fetal malformation.
Figure 1a: Ultrasound at 8 weeks showing the cephalic pole or end. The echo-free space behind the hindbrain is the rhombencephalic cavity. It must not be mistaken for an abnormality.
Figure 1b: By 11 weeks gestation, the echogenic choroid plexuses are the most prominent intracranial structures and fill the lateral ventricles. The brain parenchyma is thin and is seen as a hypoechoic peripheral rind in the frontal region. The thalamus and midbrain are visible more caudally. Ossified frontal and parietal bones are seen.
Figure 2: Coronal and sagittal transabdominal ultrasound images of the fetal head show an absent cranial vault and an amorphous mass of neural tissue. The facial structures and orbits are present.
Figure 3: Image of the fetal head shows an occipital encephalocele with brain tissue herniating through defect in the occipital bone.
Figure 4: Image of the fetal head showing an occipital myeloencephalocele with meninge and brain tissue herniating through defect in the occipital bone.
Figure 5: Axial transabdominal ultrasound image of the fetal head showing bilateral frontal indentation and ventriculomegaly. The figure also shows the aborted fetus.
Figure 6: Ultrasound image of the fetal head showing ventriculomegaly.
Figure 7: Sagittal ultrasound image of the fetal lumbosacral region showing a meningomyelocele. Axial sagittal transabdominal ultrasound image of the fetal head shows lemon sign and ventriculomegaly. Bilateral frontal indentation and a dangling choroidplexus and convexity of the lateral wall of the cerebellum shows banana sign.
Figure 8: Ultrasound image showing dysplasia of the spine.
Figure 9: Image showing cystic hygroma and the aborted fetus.
Figure 10: Ultrasound image of cystic hygroma.
Figure 11: Image showing ossification of the nasal bone
Figure 12: Image showing cystic hygroma and lemon sign in the scalp.
Figure 13: Fetal with cystic hygroma.
Figure 14: Ultrasound showing CAV, absent nasal bone, hyperechogenic bowel and the aborted fetus.
Figure 15: Ultrasound showing abnormal bowel with oligohydramnios imperforated anus which was confirmed by pathology tests after pregnancy loss.
Figure 16: Image showing polycystic kidney.
Regarding symptoms during pregnancy, 93.7% of the women had vomiting, and around 20% had gestational diabetes and hypertension (Table 2). The majority of women experienced headache, cough, dizziness, nasal discharge, and sore throat during their pregnancy. Around 10% visited the emergency department during their pregnancy; the main reason was due to experiencing contractions.
For the delivery mode, 82 (51.6%) had cesarean section (CS), 60 (37.7%) had normal vaginal delivery (NVD), 16 (10.1%) aborted and 1 (0.6%) had intra-uterine fetal death (IUFD) (Table 2).
Neonatal characteristics, 35 (25.2%) were admitted to the neonatal intensive care unit; the main reason was for respiratory distress. The first trimester ultrasound of 31 women (19.5%) showed congenital anomalies of their fetus (Table 3). Of the 31, 9 (29.0%) had malformation in the central nervous system (CNS) and brain acrania 3 (9.7%) Ventriculomegaly3(9.7%) Encephalocele 2 (6.5%) Dandy-Walker syndrome1(3,2%)as well as face and neck absent nasal bone 6 (19.4%) cystic hygroma 3(9.7%), 7 (22.6%) had cardiac malformation complete atrioventricular canal defect (CAVC)4 (12.9%) tetralogy of Fallot 1(3.2%)Ventricular septal defect2 (6.5%), 2 (6.5%) had gastrointestinal anomaly esophageal atresia 1(3.2%) imperforate anus 1(3.2%), renal malformation polycystic kidney 2 (6.5%), and skeletal defect, spina bifida 1 (3.2% )dysplasia of the spine 1 (3.2%) while 12 (38.7%) had other types of anomaly such as Down Syndrome8 (25.8%) and anomaly in the umbilical cord 1( 3.2%) and limbs absent hand 1 (3.2%) symbrachydactyly 1 (3.2%) nanism 1( 3.2%)(Table 3). Multiple anomalies were more common than isolated malformation (71.0%% vs. 29.0% respectively).
For pregnancy outcome, of the 31 who had malformation, 10 (32.3%) aborted, 1 (3.2%) had IUFD, 9 (29.0%) delivered through NVD, and 11 (35.5%) had CS. Of the 20 who delivered by NVD or CS, 8 (40.0%) of the neonates died directly after delivery or after few days.(Table 4).
The relation between maternal characteristics and fetal malformation, of the women who consumed folic acid before pregnancy, 88.9% did not have fetal malformation and only 11.1% had malformation (p-value=0.02). Other factors such as age, consanguinity, and maternal illness were not significantly associated with fetal anomaly (Table 5).
The following are ultrasound images of some of the women included in the study.
Discussion
The major outcome of the present study was that the prevalence of fetal anomaly detected using first trimester ultrasound was 19.5%. The most common types of malformation were in the central nervous system and brain as well as face and neck (29.0%), followed by Down Syndrome (25.8%), then comes cardiac anomaly (22.6%). Of those with fetal anomaly, 10 cases had abortion, 1 case had IUFD, and 8 neonates passed away directly or within few days after delivery.
The prevalence of congenital anomalies and types vary depending on the population assessed as well as the time of diagnosis. Dulgheroff et al reported in their study conducted in Brazil that the prevalence of structural defects was 2.95% during the prenatal period and 7.24% in the postnatal period [13]. A study in India showed that 1.95% of congenital anomalies were detected in the first trimester [14]. Another study reported that the overall rate of congenital anomalies in the studied population was 2.6%. Out of them, 64.4% were detected during first trimester anomaly scan while 35.6% were detected during mid gestation scan [7]. A study carried out by Sallout et al in Saudi Arabia reported that the antenatal prevalence of major congenital anomalies was 5.2% and the birth prevalence of major congenital anomalies was 4.6% [15]. A study in Egypt mentioned that anatomical anomalies were detected in 9.4% of cases who were in their late first or early second trimester [6]. We postulate that the higher prevalence of anomalies observed in the present study may have been due to the fact that the study was conducted in a private clinic and physicians refer to that private clinic when they have anomalies cases. Additionally, other studies were conducted in medical centers that have large number of patients in comparison to the small number of patients at the clinic.
Regarding the most common types of fetal anomalies, similar to our study, Kashyap et al reported that central nervous anomalies had the highest prevalence (33%) [8]. Dulgheroff et al and Sallout et al mentioned that genitourinary tract anomalies were the most frequently diagnosed [13, 15]. Other studies found that neck and abdominal wall defects were the most common [14, 16]. Similarly, multiple anomalies were more likely to be identified than isolated malformations. Rajesh et al reported 60% multiple versus 44% single defects while Sallout et al had 66.6% multiple and 33.4% isolated anomalies [14, 15].Similar to our study multiple anomalies were more common than isolated malformation (71.0%% vs. 29.0% respectively).
Several factors influence the occurrence of fetal anomalies. One of these factors is consanguinity [13, 15]. However, in the current study, the percentage of consanguinity was similar in the malformation versus no malformation cases ; this is because most of patients are from Beirut and consanguinity rate is decreasing in urban areas . Moreover, prenatal folic acid deficiency has been correlated with neural tube defects, a common congenital anomaly [15]. A study concluded that there was a significant reverse relationship between folic acid consumption during the first trimester and the risk of developing anatomical anomalies [6]. The present study also showed that women who consumed folic acid before pregnancy had less fetal malformation Around 45% of the women in this study took folic acid preconception. This rate is higher than that reported by Dulgheroff et al (8.3%) and Fouad et al (6.8%) [6, 13] These patients have knowledge about importance of folic acid from previous pregnancy and some woman takes iron and acid folic routine. A study also found that the rate of anomalies was significantly higher among women with chronic diseases such as diabetes and hypertension [6]. However, this association was not observed in our study.
Regarding the pregnancy outcome of women with fetal malformation in this study, 32.3% had abortion, 3.2% had IUFD, and 64.5% had live births of which 40.0% experienced neonatal death. A study by Bardi et al mentioned that 56.3% of women with fetal anomaly resulted in termination of pregnancy, 6.3% in spontaneous fetal demise, and 37.5% in live births [17]. Another study reported lower rates such as 3.4% had termination of pregnancy and 0.2% had abortion in high-risk patients [7]. More live birth because more woman refuse termination of pregnancy like our study.
Detection of congenital malformation has improved in the past few years mainly due to advancement in ultrasound technology and enhancement in the skills of sonographers [7, 15]. Furthermore, several studies reported that detailed examination of fetal anatomy during the first trimester provides a comprehensive assessment of fetal anatomy and can detect a considerable percentage of major structural defects [14, 16, 18]. This might explain the increased number of malformation cases currently being diagnosed compared to the past [15]. This in turn would aid in improving the management of cases with anomaly during both the prenatal and postnatal periods [15]. Multidisciplinary teams that may include obstetricians, fetal medicine specialists, geneticists, and neonatologists would help in the diagnosis and management processes [16].
Our study has some limitations. First, the data were collected from a private clinic in Beirut and not were not multi-centered. Second, the retrospective nature of the study ,and the small sample size, and being a referral clinic make it less possible to generalize the outcomes to other populations.
Discussion
In conclusion, first trimester ultrasound is essential for early diagnosis of congenital malformation. Being equipped with advanced ultrasound machines and having experienced sonographers who dedicate enough time to perform the scan would improve the quality of the imaging and increase the accuracy of the diagnosis. This in turn would help in providing counseling to parents thereby guiding them during the antenatal and postnatal periods.
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