Abstract
Objective
To evaluate the indications and methods of termination of pregnancy (TOP) and to identify maternal complications that occur during TOP.
Materials and Methods
This retrospective study was conducted at a single tertiary center with a total of 231 patients who underwent TOP from April 2019 to March 2023. The patients were divided into two groups based on gestational age at the time of TOP and the presence of complications. Group 1 consisted of patients with a gestational age of 11-22+6 weeks (n=196), while Group 2 comprised patients with a gestational age of 23-30 weeks (n=35). Additionally, the patients were categorized based on complications into those with complications (n=63) and those without complications (n=168). The TOP protocol involves misoprostol, a uterine balloon, a combination of misoprostol and balloon, or oxytocin. Procedure-related complications included the following: Rehospitalization, rest placenta, infection, uterine rupture, blood transfusion, and repeated manual vacuum curettage.
Results
The median gestational age at TOP was 18.0±3.3 weeks for women without complications and 19.5±5.1 weeks for those with complications, it was 19.5±5.1 weeks (p=0.037). In the group with complications, the combined misoprostol-balloon method was used significantly more frequently, and the rate of previous cesarean sections was higher (p<0.05). The induction time was longer in the oxytocin group (p<0.05). The misoprostol-balloon combination group had the highest rate of uterine rupture (p<0.05).
Conclusion
TOP during advanced gestation is associated with increased rates of maternal complications, such as increased transfusion, uterine rupture, and hysterotomy. Higher gestational age and previous uterine surgery are the main causes of TOP-related maternal complications.
PRECIS: Termination of pregnancy in advanced gestation is associated with increased maternal complications such as increased transfusion, uterine rupture, and hysterotomy.
Introduction
Congenital anomalies include fetal structural and functional disorders(1, 2). Major fetal anomalies are detected in 2-3% of all live births(1). The incidence rate of fetal anomalies leading to intrauterine pregnancy loss and termination of pregnancy (TOP) can reach 4-5%(2). Through the efforts to include every pregnant woman in modern obstetric care and pregnancy follow-up and the enhanced utilization of technology in obstetric examinations, the detection of fetal structural defects has increased and become possible in earlier weeks of pregnancy(3). Even life-compatible forms of structural fetal defects cause parents to reassess their decisions concerning the continuation of pregnancy because of the difficulty in determining the prognosis of the newborn’s mental state at later ages(4). The advancement of technology and its subsequent implementation in obstetrics have led to the development of antenatal screening tests and the increased detection of fetal and chromosomal abnormalities in the antenatal period through the widespread utilization of comprehensive anatomical screening at 18-22 weeks of gestation(5). Consequently, parents and their relatives are now confronted with more situations that may necessitate the consideration of TOP.
In our country, the consent of the mother and father is sufficient for TOP within the first 10 weeks of pregnancy (law no. 2827-5, 1983 Population Planning Law). For TOP at 10 weeks of gestation and above, signatures from at least two specialist physicians or a council decision are required. While pregnancy termination is performed upon the request of patients in 113 countries worldwide, it is prohibited in 86 countries(6, 7). TOP requires addressing medical problems and social, ethical, and belief-related issues. Medical problems are encountered when determining the reasons for pregnancy termination, both during and after the termination process(8). Maternal diseases, previous surgery, and increased gestational age have been reported to increase the rate of complications at every stage of the termination process(9). Nevertheless, only a limited number of studies exist, and these studies show considerable inconsistencies regarding the maternal outcomes of first- and second-trimester abortion in heterogeneous groups(10).
This study aimed to analyze TOP data from our clinic, which has substantial experience in TOP, and to identify and present the dependent factors that contribute to the incidence of complications during termination management.
Materials and Methods
This retrospective study was conducted at a single tertiary hospital. Patients between the ages of 18-44 years who underwent pregnancy termination in the high-risk pregnancies unit of the tertiary center from April 2019 to March 2023 were included in the study. The principles of the Declaration of Helsinki were followed. Approval for the study was received from the Ankara Bilkent City Hospital Clinical Research Ethics Committee (decision no: E2-23-3732, date: 27.03.2023). All patients who were included signed an informed consent form.
The clinicodemographic data of the patients, body mass index (BMI) values, gestational week at which fetal anomalies were diagnosed, indications for termination, gestational week at which pregnancy was terminated, termination methods, length of hospital stay, hemoglobin level before and after the procedure, delta hemoglobin value as an indicator of the change in the amount of hemoglobin, and complications that occurred during and after the procedure were retrospectively recorded by screening the hospital’s database. Complications included uterine rupture, resting placenta, rehospitalization, infection treatment, and repeated manual vacuum curettage.
Patients with multiple pregnancies and those with intrauterine pregnancy loss detected before hospitalization for pregnancy termination were excluded from the study. The patients included in the study were divided into two groups according to the gestational age at the time of termination. Group 1 [from the earliest week included in the study (11 weeks) to the 22nd week of gestation corresponding to the viability limit in terms of estimated fetal weight] and Group 2 (from the 23rd gestational week to the 30th gestational week, which was the latest gestational week included in the study). Pregnancies presenting with more than one anomaly were classified by considering the primary indication leading to pregnancy termination. We grouped patients with neural tube defects separately because of their large number and broad clinicophysiological outcomes.
Our hospital is an important multidisciplinary, tertiary reference center serving approximately 8-9 million individuals, including those living in nearby provinces. Patients are referred to TOP due to fetal anomalies or maternal diseases detected either during routine examinations or during secondary anatomical screening performed at 18-22 weeks of gestation. Antenatal screening tests and detailed anatomical screening at 18-22 weeks of gestation are undertaken with an ultrasound examination in all pregnant women who are followed up. Detailed counseling is provided to patients whose pregnancy is to be terminated for any reason. Chromosomal analysis is performed on samples obtained via chorionic villus sampling, amniocentesis, or cordocentesis. Patients undergo a thorough evaluation by a multidisciplinary council of experts from branches relevant to the characteristics of fetal anomaly and maternal disease, with the routine participation of specialists in perinatology, genetics, and neonatology. The termination process begins with obtaining signatures from the mother and father on a detailed consent form. All pregnancy terminations are performed in the high-risk pregnancy unit of our hospital. There is no gestational age limit for TOP in our country.
The method used in our unit for pregnancy termination consists of the misoprostol protocol according to international guidelines and balloon application using a Foley catheter, depending on gestational age and uterine surgery history(11-13). In patients with detected induction failure and a history of three or more cesarean sections, direct hysterotomy is performed. In later weeks of gestation, TOP may be preferred by administering oxytocin. A signature is obtained on the informed consent form indicating the methods and medications to be administered before termination. The decision to feticulate is made according to the estimated fetal weight and gestational age when the fetus is above the viability limit (above 21-22nd weeks of gestation). Manual vacuum curettage is performed in cases where retained products of conception are suspected after termination.
Statistical Analysis
SPSS v. 22.0 (SPSS Inc., Chicago, IL, USA) was used for data analysis. The Kolmogorov-Smirnov and Shapiro-Wilks tests were used to analyze the suitability of the data for a normal distribution. The chi-square test was used to compare categorical variables. Student’s t-test was used to compare normally distributed variables. Descriptive statistics are presented as means, standard deviations, and percentages. A p-value 0.05 was considered statistically significant.
Results
A total of 231 patients who underwent pregnancy termination were included in the study. There were 196 patients in Group 1 (11-226/7 weeks of gestation) and 35 patients in Group 2 (23-30 weeks). Age, gravida, parity, and miscarriage rates were similar in both groups, and there was no statistically significant difference. However, there was a statistically significant difference in BMI (p=0.044) (Table 1).
The length of hospital stay of the patients in both groups was similar, and there was no statistically significant difference (p=0.430). No statistically significant difference was found between the pre-and post-termination hemoglobin levels of Groups 1 and 2 or the delta hemoglobin values showing the change in hemoglobin (Table 1).
No significant difference was observed throughout the groups for the gestational age at which the anomaly or maternal disease that caused the TOP was diagnosed (p=0.564); however, the gestational age at which pregnancy was terminated statistically significantly differed (p<0.001).
The most common indication for TOP in group 1 was neural tube defect (27%), followed by anhydramnios (22.9%), other anomalies originating from the central nervous system (CNS) (15.8%), trisomies (13.3%), and other anomalies originating from the skeletal-muscular system (7.7%). Similarly, in group 2, neural tube defect (45.7%) constituted the most common indication of TOP, and this was followed by fetal cardiac diseases (34.3%), trisomies (11.4%), anhydramnios (5.7%), and other anomalies originating from the CNS (2.9%) (Table 2).
The rates of rehospitalization and systemic infections were similar between the two groups. However, the rate of rest placenta after TOP was significantly higher in group 2 (10.2% vs. 37.1%, p<0.001). The repeat manual vacuum curettage rate was significantly higher in group 2 than in group 1 (8.7% vs. 22.9%, p<0.013). The rate of uterine rupture during TOP was significantly higher in group 2 than in group 1 (p=0.012). The requirement for blood transfusion during pregnancy termination was significantly higher in group 2 than in group 1 (p=0.009) (Table 3).
The complication rate during TOP was 27.2% (n=63). In women without complications, the median gestational age at TOP was 18.0±3.3 weeks, whereas in those with complications, it was 19.5±5.1 weeks (p=0.037) (Table 4). In the group with complications, the combined misoprostol-balloon method was used significantly more frequently as a termination method, and the rate of previous cesarean section was higher (p<0.01, p<0.034).
The induction time was longer in the oxytocin group. The misoprostol-balloon combination group had the highest rate of uterine rupture (p=0.012) (Table 5). The hysterotomy rates did not differ between the groups. In the group that used the combination method (misoprostol and balloon), the hysterotomy rate was 8.3%; in the group that terminated the balloon method, the hysterotomy rate was 0%; in the group that terminated the balloon method, the hysterotomy rate was 10%.
None of the patients developed complications requiring hysterectomy. There was no maternal deterioration that required follow-up in the intensive care unit or resulted in maternal death.
Discussion
This study aimed to examine the indications and methods of TOP, complications during and after the procedure, and factors predicting these complications. The most common reason for termination was found to be CNS anomalies. Maternal complications, such as rest placenta, uterine rupture, and transfusion need, were more frequent in terminations at an advanced gestational age. Misoprostol-balloon method was associated with higher TOP-related uterine rupture.
TOP is a process in which difficult decisions are made for family and relatives(14). This process’s medical and social management, which is closely affected by social rules, traditions, beliefs, and laws, poses difficulties for families and healthcare providers(15-17).
Previous studies have identified CNS defects as the predominant cause of TOP during the second and third trimesters(18-20). In the current study, neural tube defects and other CNS anomalies were the most common reasons for TOP in both groups, which is similar to the results of many related studies. Concerning hysterotomy performed due to pregnancy termination, Aslan et al.(21) reported non-significant rates. Similarly, we found no significant difference in the hysterotomy rates between the groups. Although no difference was observed between the groups in terms of the week of diagnosis of the anomaly or maternal disease that led to termination, differences were noted in the weeks of pregnancy termination. These results could be attributed to the prolonged decision-making process of patients diagnosed at earlier stages of pregnancy and the misconception that the identified issue can be remedied with further advancement in gestational weeks.
Another finding of our study was that the rate of feticide applied for pregnancy termination increased as the gestational age approached the fetal survival limit, resulting in a significant difference between the groups. This finding is in agreement with previous studies(19, 22). Special conditions caused by the physiology of pregnancy and obstetric history affect the rates of complications that may occur during pregnancy termination(23). Research on maternal complications that occur during pregnancy termination has shown that increasing gestational age, previous surgery, and the number of previous surgical procedures are associated with possible complications(24, 25). In this study, we observed a significantly higher rate of rest placenta and the subsequent requirement of repeat manual vacuum curettage among patients who underwent pregnancy termination in advanced weeks of gestation (especially later than the 22nd week). Although this rate was similar to that reported by Garofalo et al.(9), Spingler et al.(25) found no difference in the rate of blood transfusion requirement between the termination method groups. In a study conducted by Garofalo et al.(9), the rate of uterine rupture was found to be non-significant. In contrast, our groups significantly differed in terms of the uterine rupture rate. All patients with ruptures had previously undergone at least one cesarean section.
We also observed that blood transfusion requirement increased with gestational age and the number of previous cesarean sections. The rate of blood transfusion requirement we determined is different from the data presented by Spingler et al.(25). Our study showed that CNS abnormalities are the main cause of top TOP and that maternal complications, such as repeated manual curettage and uterine rupture, increase in late TOP. This situation emphasizes the importance of making the decision for TOP as early as the first week of pregnancy and taking a multidisciplinary approach because many factors can influence the decision. The complication rates varied depending on the termination method. The misoprostol + balloon combination was found to be associated with serious complications, such as uterine rupture. The balloon plus misoprostol method is generally preferred in advanced-stage pregnancy and in patients undergoing previous uterine surgery. Therefore, the high complication rate may depend on the week of pregnancy when the method is used(25).
A strength of our study is that the indications for TOP, termination methods, and maternal complications were examined in detail in the same study.
Study Limitations
Our study had some limitations, including its retrospective design and reliance on data from a single center.
Conclusion
Each patient who will undergo pregnancy termination should be evaluated individually, including the gestational age at which the procedure will be performed and their obstetric history. TOP during advanced gestation is associated with increased maternal complications, such as increased transfusion, uterine rupture, and hysterotomy.
