Association of appendectomy for acute appendicitis in pregnancy with adverse obstetrical outcomes

doi:10.21203/rs.3.rs-3330312/v1

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Association of appendectomy for acute appendicitis in pregnancy with adverse obstetrical outcomes

https://doi.org/10.21203/rs.3.rs-3330312/v1

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Background

Acute appendicitis (AA) in pregnancy is associated with miscarriage and preterm birth. Even if undergoing appendectomy, pregnant women still have a risk of miscarriage or preterm birth. The aim of this study was to assess the risk factors associated with miscarriage and preterm birth, as well as the impact of these risk factors on gestational age at delivery among patients who had confirmed AA and received appendectomy.

Methods

A single-center retrospective case‒control study was performed. Clinical information was documented, and relationships between variables and outcomes were assessed by univariate and multivariate logistic or linear regression analyses reaching a significance of p value < 0.05.

Results

A total of 91 pregnant women were included and were divided into miscarriage or preterm birth (n = 31) and term birth (n = 60) groups. There were no significant differences in the demographic characteristics of the studied population. Anorexia was an independent risk factor that was associated with miscarriage or preterm birth (OR 9.80, 95% CI 1.70-56.34). The time from symptom onset to appendectomy among patients with miscarriage or preterm birth was significantly longer than that among patients with term birth (OR 1.03, 95% CI 1.00-1.06), and they had a significantly earlier gestational age at delivery, with a difference of 1.68 weeks.

Conclusions

Appendectomy should be performed as soon as possible for pregnant women with highly suspected or confirmed AA. Delayed appendectomy and prolonged time from symptom onset to appendectomy increase the risk of miscarriage or preterm birth. Anorexia was another independent risk factor for miscarriage or preterm birth, which should be given due attention.

Trial registration

Retrospectively registered.

Acute appendicitis

Miscarriage

Premature birth

Appendectomy

Risk factors

Acute appendicitis (AA) is the most common surgical acute abdominal pain during pregnancy, with an incidence of 0.06–0.55%[1], and occurs equally throughout the three pregnancy trimesters[2]. Among pregnant women with confirmed AA, early appendectomy remains the standard treatment to reduce the risk for adverse obstetrical outcomes, mainly including miscarriage and premature birth[3]. However, the diagnosis of AA during pregnancy is challenging due to special anatomic and physiological changes supporting fetal development, even using ultrasonography[2, 4]. Notwithstanding undergoing appendectomy for AA, pregnant women still have a risk for miscarriage and premature birth[1]. Therefore, identifying at-risk pregnant women and taking appropriate protective measures during the perioperative period are tremendously important. Previous studies among patients with appendectomy found that fever > 38°C, maternal age, acute complicated appendicitis and symptom onset to operation greater than or equal to 48 hours were independent predictors for adverse obstetrical outcomes[5, 6]. The aim of this study was to assess the risk factors associated with miscarriage and preterm birth among pregnant women with AA undergoing appendectomy, as well as the impact of these risk factors on gestational age at delivery.

A single-center retrospective case‒control study based on the electronic medical records system was conducted among pregnant women who were diagnosed with AA and underwent appendectomy from August 2007 through August 2018 at the Peking University Third Hospital (PUTH), a major tertiary academic teaching hospital located in Beijing, China. The study was performed following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines [7] and in accordance with the Declaration of Helsinki. It was approved by the Ethics Committee of PUTH (PUTHIRB-201945301).

Patient selection

All enrolled patients had histopathologic AA, and their complete obstetrical outcomes could be obtained from the electronic medical record system or were accrued from patients with informed consent who delivered in other medical institutions but could offer gestational age at delivery and birth weight through follow-up calls. Patients were excluded when they had incomplete medical records, received other surgeries at the time of appendectomy, or were unable to provide obstetric data during the follow-up call.

Clinical data collection

Data collection included demographics, clinical characteristics, laboratory and radiological findings, and surgical and obstetrical data. Demographics included age, gestational age at the first onset, prepregnancy body mass index (BMI, kg/m²) for the last pregnancy, and history of childbirth, cesarean section and miscarriage. Clinical characteristics included nausea or vomiting, anorexia, fever (body temperature over 37.3°C), metastatic abdominal pain, right lower quadrant tenderness, rebound tenderness, abdominal wall rigidity, and diarrhea. Laboratory findings included white blood cell (WBC) count and neutrophilia percentage. Ultrasound results were the main radiological findings, which were suggestive of AA and included a dilated and incompressible appendix with a diameter > 6 mm and wall > 3 mm or peri-appendiceal echogenic fat, effusion or abscess[8]. Surgical data included time from symptom onset to operation (symptom duration), operative method and duration, gestational age at appendectomy, and histopathologic findings. Histopathologic findings classified acute appendicitis into two types: acute uncomplicated appendicitis and acute complicated appendicitis. The former included acute simple and suppurative appendicitis, while the latter included acute perforated appendicitis, peri-appendicular abscess, and gangrenous appendicitis[9]. Obstetrical data included gestational age at delivery and birth weight. The gestational age at delivery determined the three trimesters and obstetrical outcomes. The first trimester was limited to the first 12 weeks during pregnancy, followed by the second trimester from the 13th to 27th weeks and the third trimester after the 28th week. Obstetrical outcomes were primary outcomes, including miscarriage, preterm birth and term birth, whose gestational age at delivery was within 19 weeks, from 20th to 36th weeks, and over 37th weeks, respectively. The birth weight of a healthy newborn ranged from 2500 to 4000 g, a low-weight newborn was less than 2500 g, and macrosomia was more than 4000 g.

Statistical analysis

Data analysis was carried out using R software (version 4.1.2). The normality tests were performed for continuous variables using the Kolmogorov‒Smirnov test. The descriptive statistics of normally distributed data are expressed as the mean ± standard deviation (SD), and nonnormally distributed data are represented by the median (interquartile range). The intergroup differences in normally distributed data were analysed with Student’s t test, while the differences in nonnormally distributed data were analysed using the Mann‒Whitney U test. Categorical variables are summarized as frequencies (percentages) and were compared using the chi-square test or Fisher’s exact test as appropriate. In this study, logistic regression was employed to assess the associated risk factors for abortion and preterm birth, the results of which were reported as odds ratios (ORs) with 95% confidence intervals (CIs). Linear regression analysis was utilized to evaluate the impact of these risk factors on the gestational age at termination of pregnancy, the results of which were reported as β with 95% CI. Both univariate and multivariate analyses were conducted to examine the influence of these factors on the outcomes of interest. A P value < 0.05 was considered statistically significant.

Patient enrollment and grouping

A total of 137 of 200 pregnant women with suspected AA underwent appendectomy and had confirmed AA in the histopathologic findings, while 63 rest were discharged without appendectomy. There were 36 patients who were unable to be followed up, and 9 patients had incomplete medical records. Only 92 of 137 complete medical records were reviewed, but one case was excluded due to simultaneous salpingectomy and appendectomy. Finally, a total of 91 pregnant women met the inclusion criteria and were included, 28 of whom had obstetrical data in the medical records system, while others were obtained from patients (Figure 1). Ninety-one women were classified into the term birth group and miscarriage or preterm birth group according to obstetrical outcomes (Figure 1).

Basic characteristics

Of the included 91 patients, 60 were term deliveries, 25 were preterm births and 6 were miscarriages. The most frequent histopathologic finding was acute uncomplicated appendicitis (59.34%, 54/91), which included simple appendicitis (9.89%, 9/91) and suppurative appendicitis (49.45%, 45/91). Acute complicated appendicitis was confirmed in 40.66% (37/91) of women, 19.78% (18/91) of whom had perforation or abscess, and the others had gangrene. First onset was present in 97.80% (89/91) of women. A total of 96.70% (88/91) of open appendectomies were completed after the initial diagnosis of AA. Appendectomy via a classical McBurney incision was performed in 91.21% (83/91) of cases. The median gestational age at delivery of all patients was 37 (6,42) weeks, while that of the term delivery group was 39 (37,42) weeks and that of the miscarriage/preterm birth group was 31 (6,36) weeks. Eight of 85 deliveries were low-weight newborns, 5 of whom had macrosomia.

A total of 49 of 91 patients underwent appendectomy within the first 19 weeks of pregnancy; miscarriage occurred in 12.24% (6/49) of these patients, and the median gestational age at delivery was 8 (6, 19) weeks (Figure 2). Seventeen of 49 women underwent appendectomy in the first trimester, with 23.53% (4/17) miscarriage and 11.76% (2/17) preterm birth, while the others underwent appendectomy from the 13^th to 19^th weeks of pregnancy, resulting in 6.25% (2/32) miscarriage. Ninety patients received appendectomy until 37 weeks of pregnancy, with 6.67% (6/90) of miscarriage and 29.76% (25/84) of preterm birth with a median gestational age at delivery of 33 (22, 36) weeks. A total of 15.38% (14/91), 10.99% (10/91), 7.68% (7/91), 7.68% (7/91), and 3.29% (3/91) of patients underwent appendectomy during the 20^th-23^th, 24^th-27^th, 28^th-31^th, 32^th-33^th, and 34^th-36^th weeks, respectively, and the incidences of preterm birth were 28.57% (4/14), 40.00% (4/10), 71.43% (5/7), 28.57% (2/7), and 66.67% (2/3), respectively. Importantly, 5 of 6 patients with miscarriage and 12 of 25 patients with preterm birth delivered within the first four weeks after appendectomy.

Risk factors for miscarriage and preterm birth

In the univariate analysis, no differences were noted with regard to demographics, such as gestational age at first onset, age, BMI and history of childbirth, cesarean section and miscarriage (Table 1). The miscarriage or preterm birth group was characterized by significantly more events of anorexia, fever, rebound tenderness and acute complicated appendicitis. WBC count and neutrophilia percentage were comparable between the groups. The 46 h median symptom duration in the miscarriage or preterm birth group was significantly longer than the 25 h median symptom duration in the term birth group. There was a significant increase in the operative duration, the median of which was 94 h in the miscarriage or preterm birth group compared with 67 h in the term birth group.

An adjusted multivariate analysis substantiated the finding that miscarriage or preterm birth was independently associated with anorexia (OR 9.80, 95% CI 1.70-56.34) and symptom duration (OR 1.03, 95% CI 1.00-1.06) (Table 1).

Table 1 The results of univariate and multivariate logistic regression analyses between term birth and miscarriage/preterm birth groups

Risk factors	Miscarriage/preterm birth (n=31)	Term birth (n=60)	OR (95%CI)	Adjusted OR (95%CI)
Demographics
Age (years)	28.84±4.13 (21.00,39.00)	29.47±4.28 (18.00,41.00)	0.96 (0.87,1.07)	1.03 (0.87,1.24)
Gestational age at the first onset (weeks)	20.55±9.24 (5.00,36.00)	18.58±7.67 (5.00,37.00)	1.03 (0.98,1.09)	1.29 (0.72,2.32)
BMI (kg/m²)	23.71±3.19 (18.30,28.60)	23.62±4.47 (16.50,34.90)	1.01 (0.90,1.12)	0.84 (0.69,1.03)
History of childbirth	8 (25.81)	20 (33.33)	0.70 (0.26,1.83)	1.14 (0.13,10.34)
History of cesarean section	5 (16.13)	8 (13.33)	1.25 (0.37,4.20)	3.84 (0.25,58.19)
History of miscarriage	8 (25.81)	18 (30.00)	0.81 (0.31,2.15)	0.37 (0.07,2.07)
Clinical characteristics
Nausea or vomiting	22 (70.97)	32 (53.33)	2.14 (0.85,5.40)	0.92 (0.18,4.59)
Anorexia	18 (58.06)	21 (35.00)	2.57 (1.06,6.26)^*	9.80 (1.70,56.34)^*
Fever	21 (67.74)	23 (38.33)	3.38 (1.35,8.44)^*	0.43 (0.08,2.43)
Metastatic abdominal pain	13 (41.94)	33 (55.00)	0.59 (0.25,1.42)	0.71 (0.14,3.53)
Right lower quadrant tenderness	27 (87.10)	47 (78.33)	1.87 (0.55,6.30)	0.58 (0.09,3.89)
Rebound tenderness	24 (77.42)	33 (55.00)	2.81 (1.05,7.50)^*	1.17 (0.23,5.92)
Abdominal muscle tension	6 (19.35)	6 (10.00)	2.16 (0.63,7.37)	2.11 (0.30,14.66)
Diarrhea	2 (6.45)	8 (13.33)	0.45 (0.09, 2.25)	0.57 (0.05,6.69)
Laboratory and radiological findings
WBC (×10³/mm³)	17.77 (14.4,19.42)	14.00 (12.29,16.95)	1.27 (1.10,1.46)^*	1.07 (0.83,1.37)
Neutrophilia percentage (%)	89.80 (88.65,92.35)	87.60 (82.95,90.43)	1.18 (1.05,1.33)^*	1.11 (0.93,1.33)
Ultrasound results	27 (87.10)	41 (68.33)	3.13 (0.96,10.21)	3.98 (0.58,27.33)
Surgical data
Symptom duration (h)	46.00 (32.50,78.50)	25.00 (18.00,41.25)	1.03 (1.01,1.05^)*	1.03 (1.00,1.06)^*
Operative duration (h)	94.00 (70.00,114.00)	67.00 (56.00,81.50)	1.03 (1.01,1.05)^*	1.03 (0.99,1.06)
Gestational age at appendectomy (weeks)	20.74±9.23 (5.00,36.00)	18.78±7.78 (5.00,37.00)	1.03 (0.98,1.08)	0.88 (0.50,1.55)
Histopathologic findings
Acute uncomplicated appendicitis	8 (25.81)	46 (76.67)	Reference	Reference
Acute complicated appendicitis	23 (74.19)	14 (23.33)	9.45 (3.47,25.74)^*	2.66 (0.50,14.33)

^*p value＜0.05

Impact of risk factors on gestational age at delivery

Univariate analysis revealed that none of the demographics had a statistically significant impact on gestational age at delivery (Table 2). Patients with nausea or vomiting, fever, rebound tenderness, acute complicated appendicitis, higher WBC count, increased neutrophil percentage, longer symptom duration, or prolonged surgical duration had a significantly earlier gestational age at delivery. The adjusted multivariate analysis revealed that only the longer symptom duration significantly contributed to a decrease in gestational age at delivery (Table 2). For every one-hour delay in appendectomy, the gestational age at delivery decreased by 0.08 weeks (β -0.08, 95% CI -0.12- -0.03). Therefore, in this study, the miscarriage or preterm birth group with a median symptom duration of 46 hours had a significantly earlier gestational age at delivery than the term birth group with a median symptom duration of 25 hours, with a difference of 1.68 weeks.

Table 2 The results of univariate and multivariate analyses in the subgroup

Risk factors	β (95%CI)	Adjusted β (95%CI)
Demographics
Age (years)	0.31 (-0.08,0.70)	0.07 (-0.30,0.44)
Gestational age at the first onset (weeks)	0.20 (-0.002,0.40)	0.60 (-0.78,1.99)
BMI (kg/m²)	0.20 (-0.21,0.61)	0.09 (-0.34,0.51)
History of childbirth	1.54 (-2.05,5.13)	-1.07 (-5.53,3.38)
History of cesarean section	1.41 (-3.33,6.15)	0.48 (-5.21,6.16)
History of miscarriage	-1.22 (-4.89,2.45)	-0.77 (-4.24,2.71)
Clinical characteristics
Nausea or vomiting	-3.77 (-7.06, -0.48)^*	-1.28 (-4.57,2.01)
Anorexia	-1.47 (-4.82,1.87)	-0.36 (-3.50,2.79)
Fever	-4.96 (-8.12, -1.81)^*	-0.43 (-3.95,3.09)
Metastatic abdominal pain	1.61 (-1.70,4.92)	0.05 (-3.17,3.28)
Right lower quadrant tenderness	-2.57 (-6.80,1.66)	-1.04 (-5.28,3.20)
Rebound tenderness	-4.61 (-7.90, -1.31)^*	-2.93 (-6.24,0.38)
Abdominal wall rigidity	-1.68 (-6.58,3.22)	1.91 (-2.77,6.60)
Diarrhea	2.71 (-2.58,7.99)	0.97 (-3.90,5.85)
Laboratory and radiological findings
WBC (×10³/mm³)	-0.57 (-1.03, -0.12)^*	0.17 (-0.39,0.73)
Neutrophilia percentage (%)	-0.38 (-0.67, -0.10)^*	-0.08 (-0.41,0.25)
Ultrasound results	-3.25 (-7.01,0.52)	0.73 (-3.20,4.66)
Surgical data
Symptom duration (h)	-0.11 (-0.15, -0.07)^*	-0.08 (-0.12, -0.03)^*
Operative duration (h)	-0.08 (-0.14, -0.03)^*	-0.04 (-0.11,0.02)
Gestational age at appendectomy (weeks)	0.19 (-0.01,0.39)	-0.42 (-1.78,0.95)
Histopathologic findings
Acute uncomplicated appendicitis	Reference	Reference
Acute complicated appendicitis	-6.80 (-9.86, -3.73)^*	-3.12 (-7.14,0.91)

^*p value＜0.05

Appendectomy is one of the most common nonobstetric surgeries during pregnancy, and it increases the risk of adverse obstetrical outcomes such as miscarriage and preterm birth[10]. This study found that symptom duration and anorexia were independent risk factors for miscarriage or preterm birth. A cohort study based on the Nationwide Inpatient Sample (NIS) data found that peritonitis and sepsis were disease-related independent risk factors for adverse obstetric outcomes after appendectomy during pregnancy[11]. Although this study did not record information on these two aspects, they are common features of acute complicated appendicitis, which is associated with the two independent risk factors found in this study.

The results of this study showed that the median symptom duration in the miscarriage or preterm birth group increased significantly by 3% compared to that in the term birth group, which resulted in delivery occurring 1.68 weeks earlier in the miscarriage or preterm birth group. Previous studies have also found that prolonged symptom duration may increase the risk of miscarriage or preterm birth, which is mainly associated with an increased risk of acute complicated appendicitis. When the symptom duration was less than 24 hours, the risk of acute complicated appendicitis was relatively low, and the rate of miscarriage and preterm birth was approximately 6%[12]. However, when the symptom duration exceeded 24 hours, the risk of appendiceal perforation could reach 66%, and the rate of miscarriage and preterm birth was approximately 36%[13, 14]. In this study, the median symptom duration in the miscarriage or preterm birth group was 46 hours, with a prevalence of acute complicated appendicitis of 74.19%, while in the full-term delivery group, the median duration of symptoms was 25 hours, with a prevalence of acute complicated appendicitis of only 23.33%. The overall incidence of miscarriage or preterm birth among all patients was 34.07%, which is consistent with previous studies[13].

This study found, for the first time, that prolonged symptom duration was an independent risk factor for earlier termination of pregnancy, whereas acute complicated appendicitis was not. A systematic review based on all patients with acute appendicitis found that compared to those with a symptom duration of 24 h as a reference, the risk of developing acute complicated appendicitis increased by 0.84 times in individuals with a symptom duration of 24–48 h and by 6.57 times in individuals with a symptom duration exceeding 48 h[15]. Although prolonged symptom duration increased the risk of acute complicated appendicitis, the rate of acute complicated appendicitis remained higher than that of miscarriage or preterm birth[14]. This study found that the impact of acute complicated appendicitis on obstetric outcomes was influenced by factors such as nausea or vomiting, fever, rebound tenderness, elevated WBC count, increased neutrophilia percentage, and prolonged operation time. Previous studies have found that longer prehospital symptom duration was more likely to result in miscarriage or preterm birth, while longer in-hospital symptom duration helped reduce miscarriage or preterm birth caused by negative appendectomy, which was associated with the use of antibiotics in the hospital setting[15]. The use of antibiotics can effectively control inflammation, alleviate the aforementioned symptoms and signs caused by inflammation, and improve inflammatory indicators such as WBC and neutrophilia percentage[16]. Therefore, for patients with a longer symptom duration, if they meet the indications for antibiotic use, timely administration of antibiotics to control inflammation should be considered. Even if postoperative pathological examination suggests acute complicated appendicitis, there is still a chance of achieving term birth.

This study found that the number of events of anorexia in the miscarriage or preterm birth group was significantly increased by 8.80 times compared to that in the term birth group. This finding was consistent with previous research, where pregnant women with eating disorders were more prone to miscarriage or preterm birth than healthy pregnant women, and the risk of miscarriage or preterm birth during pregnancy was higher than that of women with preexisting eating disorders before pregnancy, mainly due to low levels of leptin[17]. Leptin is a hormone released by fat cells after eating that regulates appetite, energy metabolism, and weight[18]. However, anorexia can lead to decreased leptin secretion. Prolonged anorexia may also result in poor nutrition and low weight gain in pregnant women, both of which have a strong causal relationship with miscarriage and preterm birth[17]. The causes of anorexia are diverse and difficult to distinguish. This symptom can occur in various situations, including normal pregnancy and acute appendicitis attacks, but its presentation is often atypical and easily overlooked. Currently, there is a lack of methods for assessing anorexia, and the impact of the duration and severity of this symptom on hormone levels, nutritional status, and weight changes in pregnant women is still unclear. This study is a retrospective case‒control study and did not obtain the aforementioned related information. Further evidence is needed to validate these results and explain the underlying mechanisms.

There were several limitations in this study. This was a single-center retrospective case‒control study. Although all available information was collected, missing information could not be discussed as described. However, the special physiological and pathological state of pregnant women with AA limits the development of prospective clinical studies, and retrospective studies are still feasible. The sample size of this study was small, and the time span involved in medical records was long. The results need to be verified with more timely research data. In addition, this study only considered patients treated with open appendectomy. Previous studies have found that open appendectomy is an independent risk factor for adverse obstetric outcomes[11]. Whether the results are equally applicable to patients with laparoscopic appendectomy needs to be analysed by additional studies.

This study evaluated the risk factors associated with miscarriage or preterm birth and their impact on gestational age at delivery. It was found that prolonged symptom duration and anorexia were independent risk factors for miscarriage or preterm birth, with prolonged symptom duration being the only independent risk factor for earlier delivery. These results confirmed the causal relationship between prolonged symptom duration and adverse obstetric outcomes. However, the underlying mechanisms linking the two are still unclear, although the most common explanation is that prolonged symptom duration increases the risk of developing acute complicated appendicitis. However, this study did not find a direct causal relationship between acute complicated appendicitis and miscarriage or preterm birth, as indicated in previous research. This suggests that the impact of acute complicated appendicitis on obstetric outcomes is determined by multiple factors. Additionally, this study also identified a correlation between anorexia and miscarriage or preterm birth, but the degree and mechanisms by which anorexia affects obstetric outcomes remain unclear. Due to limitations in conducting prospective clinical studies and the potential for missing important information in retrospective clinical studies, animal experiments may be considered as alternative adjunct evidence.

AA: Acute appendicitis.

Acknowledgements

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Funding

Not applicable.

Availability of data and materials

All data generated or analysed during the current study are available from the corresponding authors upon reasonable request.

Authors’ contributions

NL and YW were responsible for the conceptualization, design, and supervision of the research. YW carried out the data acquisition. YG and NL performed the statistical analysis and interpretation. YG drafted the manuscript, with NW, NL and YW providing critical revisions. All authors listed have made substantial contributions and approved the final manuscript.

Ethics approval and consent to participate

The study was performed following the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines and in accordance with the Declaration of Helsinki. The study was approved by the Ethics Committee of Peking University Third Hospital (PUTH) (PUTHIRB-201945301). Informed consent to participate was obtained from all participants.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Lipping, E., et al., Open versus laparoscopic appendectomy for acute appendicitis in pregnancy: a population-based study. Surg Endosc, 2023.
Le, T.D., et al., Diagnostic performance of magnetic resonance imaging for diagnosing acute appendicitis during pregnancy. Eur Rev Med Pharmacol Sci, 2023. 27(8): p. 3489-3499.
Ball, E., et al., Evidence-Based Guideline on Laparoscopy in Pregnancy: Commissioned by the British Society for Gynaecological Endoscopy (BSGE) Endorsed by the Royal College of Obstetricians & Gynaecologists (RCOG). Facts Views Vis Obgyn, 2019. 11(1): p. 5-25.
Dongarwar, D., et al., Trends in Appendicitis Among Pregnant Women, the Risk for Cardiac Arrest, and Maternal-Fetal Mortality. World J Surg, 2020. 44(12): p. 3999-4005.
Yoo, K.C., et al., Could laparoscopic appendectomy in pregnant women affect obstetric outcomes? A multicenter study. Int J Colorectal Dis, 2016. 31(8): p. 1475-81.
Choi, Y.S., et al., Clinical Characteristics of Acute Appendicitis in Pregnancy: 10-Year Experience at a Single Institution in South Korea. J Clin Med, 2023. 12(9).
von Elm, E., et al., The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies. Int J Surg, 2014. 12(12): p. 1495-9.
Pelin, M., et al., Acute appendicitis: Factors associated with inconclusive ultrasound study and the need for additional computed tomography. Diagn Interv Imaging, 2018. 99(12): p. 809-814.
Eddama, M., et al., Logistic regression model to predict acute uncomplicated and complicated appendicitis. Ann R Coll Surg Engl, 2019. 101(2): p. 107-118.
Haataja, A., et al., Non-obstetric surgery during pregnancy and the effects on maternal and fetal outcomes: A systematic review. 0(0): p. 14574969231175569.
Sachs, A., et al., Risk Factors and Risk Stratification for Adverse Obstetrical Outcomes After Appendectomy or Cholecystectomy During Pregnancy. JAMA Surg, 2017. 152(5): p. 436-441.
Ishaq, A., et al., Location of appendix in pregnancy: does it change? Clin Exp Gastroenterol, 2018. 11: p. 281-287.
Copson, S. and E. Nathan, Surgery in pregnancy: Identifying factors contributing to variation and delay in diagnosis and management of appendicitis in pregnancy. Aust N Z J Obstet Gynaecol, 2021. 61(4): p. 500-504.
Nakashima, M., M. Takeuchi, and K. Kawakami, Clinical Outcomes of Acute Appendicitis During Pregnancy: Conservative Management and Appendectomy. World J Surg, 2021. 45(6): p. 1717-1724.
Li, J., et al., Effect of Delay to Operation on Outcomes in Patients with Acute Appendicitis: a Systematic Review and Meta-analysis. J Gastrointest Surg, 2019. 23(1): p. 210-223.
Loftus, T.J., et al., Successful nonoperative management of uncomplicated appendicitis: predictors and outcomes. J Surg Res, 2018. 222: p. 212-218.e2.
Sebastiani, G., et al., Eating Disorders During Gestation: Implications for Mother's Health, Fetal Outcomes, and Epigenetic Changes. Front Pediatr, 2020. 8: p. 587.
de Assis, G.G. and E. Murawska-Ciałowicz, Exercise and Weight Management: The Role of Leptin-A Systematic Review and Update of Clinical Data from 2000-2022. J Clin Med, 2023. 12(13).

No competing interests reported.

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Association of appendectomy for acute appendicitis in pregnancy with adverse obstetrical outcomes

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