When major fetal anomalies are diagnosed, optimisation of prenatal counselling for pregnant women requires understanding the factors affecting parental decisions to terminate or continue the pregnancy in the relevant population. In this study, the rate of TOP owing to fetal anomalies was 57.3%, which is higher than that reported in most previous studies with similar legal gestational age limits [4-6]. Data from the New Jersey Fetal Abnormalities Registry, which has a majority White population, showed a 33% rate of TOP when fetal defects were identified before 24 gestational weeks [5]. One explanation for the higher TOP rate in our study may have been that the rate of lethal fetal anomalies, a significant factor affecting parents’ decisions, was greater than that in the New Jersey study (51.4% vs 27.8%).
The lack of an efficient congenital anomalies registration system in developing countries, especially in South-East Asia, leads to inadequate information regarding TOP rates for fetal anomalies, prenatal diagnosis rates, and fetal and neonatal outcomes. Interestingly, Ho et al. reported no incidence of TOP for 38 fetal anomalies detected during the antenatal period in Malaysia and concluded that TOP for fetal anomalies was infrequent in developing countries [12]. However, the important limitations of that study were its small number of cases and a failure to mention the gestational age at prenatal diagnosis and the legal gestational limit in Malaysia. In our study, over half of the 461 prenatal patients elected TOP when the fetal anomalies were detected before 24 gestational weeks. These different results from countries in the same region illustrate the necessity of an effective data collection and registration system for congenital anomalies in developing countries. This information could help improve the quality of prenatal care systems in this region.
Expectedly, lethality and genetic abnormalities played important roles in the parental TOP decisions, and we found a strong predictive relationship between these two factors and TOP [5, 6, 9, 11]. Various techniques for fetal therapy have been developed but are not generally accessible, and treatment outcomes are often unsatisfactory, especially in developing countries. Furthermore, in low-resource countries, health care systems for children with congenital anomalies are often inaccessible because specialists are limited to a few university hospitals. Moreover, patients with disabilities in developing countries often have a poor quality of life [14]. Consequently, parental consideration of the quality of life for their children with severe birth defects, the potential for disability and/or developmental delays, and the burden of caring for these children may guide parents to elect TOP [15].
Considering the influence of fetal lethality on parental decisions, lethal and potentially lethal anomalies, anencephaly, bilateral renal agenesis or severe urinary tract obstruction, meningocele or encephalocele, monosomy X with hydrops fetalis and Bart’s hydrops fetalis had TOP rates of 100% in our study (Table 2). Surprisingly, a study from Israel found that the TOP rates for these same anomalies diagnosed before 24 gestational weeks were only 22%–50% [4]. The only profound predictors of termination decisions in that study were an earlier gestational week at diagnosis and previous uncompleted pregnancies; presumed fetal lethality was not a predictor. This difference demonstrates that TOP rates and factors affecting parental decisions vary among countries depending on the TOP laws and on the population backgrounds.
Early diagnosis at <20 gestational weeks was an important independent factor in the parents’ decisions. Patients with an earlier diagnosis of fetal anomalies tended to terminate the pregnancy more frequently than did those with a later diagnosis. Our findings are consistent with previous studies from developed countries [4, 5, 7], possibly because the maternal-fetal bonding that occurs as the gestational weeks progress makes the TOP decision more emotional and difficult for parents. Later diagnoses also make the TOP more difficult and increase the risk of complications [1, 16]. In Thailand, ultrasound anatomy screening at 18–22 gestational weeks is a national policy, and some fetal anomalies can be detected as early as the first trimester [17]. Therefore, pregnant women should be encouraged to obtain early antenatal care. Additionally, obstetricians should be broadly educated and trained in early comprehensive ultrasounds and prenatal diagnoses to detect high-risk cases because early diagnoses of fetal anomalies at <20 gestational weeks, as well as genetic abnormality involvement, affect parents’ management plans.
A semi-structured interview study by Phaophan et al. showed that having a Buddhist background did not influence the decisions of pregnant Thai women to terminate their pregnancy when fetal ß-thalassemia was detected [18]. The primary religious background of the pregnant women in our study was Buddhist, and all data were declared and collected from patients’ medical records; however, these data may not represent patients’ actual beliefs. Consequently, to fully understand the patients in this region, further qualitative studies with in-depth interviews should be conducted to determine the factors, especially religious and sociocultural factors, associated with parental decisions.
Because of the scarcity of other subspecialists and the complexity of the interdepartmental referral system within the pregnancy timeframe, only 17% of our couples received counselling by a multidisciplinary team. Although discussions with specialists who have their own expertise and different perspectives can improve parental decision making, especially regarding complex or uncommon fetal anomalies, in terms of ethical and management options during the prenatal and postnatal periods, the New Jersey study stated that genetic counselling did not appear to play an important role in parental decisions [5, 19-21]. This may reflect the high-quality targeted counselling and the substantial amount of time with MFM specialists available in the U.S. Therefore, the counselling techniques of the MFM team should be improved, and interdepartmental referral systems for fetal anomaly cases should be coordinated. The effect of a multidisciplinary team approach on parental decisions and satisfaction in developing countries requires further studies.
This study is the first to report the TOP rate and the factors that influence it for fetal anomalies in Thailand, a middle-income developing country. The results highlighted that fetal information, including gestational age, structural abnormalities and genetic involvement, should be evaluated and considered during prenatal care and counselling. Therefore, a comprehensive fetal anatomical scan and prenatal diagnosis at as early as 20 gestational weeks should be offered in antenatal care clinics.
The main limitation of this study was its retrospective nature, which precluded any control over the counselling techniques used by the various MFM staff over the past 10 years. A non-directive method is the standard technique; however, each counsellor may have their own convictions and perspectives regarding TOP, as well as varying counselling skills, which could affect parental decisions [21]. Another limitation was that the results were from a single university hospital in the capital city of Thailand; hence, these results may not be generalisable to hospitals in other parts of Thailand or to other countries with different sociocultural backgrounds. However, pregnant women from regions nationwide travelled to the capital city and enrolled in this study; therefore, the findings may represent those of the entire Thai population and could correspond to other developing countries to some extent.