Abstract
Purpose
The influence of pregnancy on tuberculosis (TB) has not been well studied. This study aimed to investigate the demographics, clinical characteristics and outcomes of pregnant-related TB compared with the general population with TB.
Methods
We retrospectively analysed medical records of women during pregnancy or within six months postpartum with active TB who were admitted to the West China Hospital between 2011 and 2022. According to age, gender and admission time, the general population with active TB was matched at a ratio of 1:2, and the demographics, clinical characteristics and outcomes were compared.
Results
All the participants in both the pregnant and non-pregnant groups were females, averaging 26 years old, with a majority of Han nationality (72.4% vs. 69.5%, respectively). The two groups were comparable (p < .05). Pregnant TB cases showed higher rates of fever (61% vs. 35%), dyspnoea (39.9% vs. 18.7%), neurological symptoms (34.4% vs. 11.0%) and miliary TB (24.5% vs. 10.9%) compared to non-pregnant cases (p < .05). Additionally, the pregnant group exhibited lower red blood cell counts (3.62 × 109/L vs. 4.37 × 109/L), lower albumin levels (31.20 g/L vs. 40.40 g/L) and elevated inflammatory markers (p < .05). Pregnant women with TB had severe outcomes, with 16.3% requiring intensive care unit (ICU) care and a 3.3% TB-related mortality rate – higher than local averages. In contrast, the non-pregnant group had lower rates (0.8% for ICU admission, and no TB-related deaths). Moreover, active TB during pregnancies led to a high rate of spontaneous abortion (34.1%), with military pulmonary TB identified as the sole risk factor for severe TB in pregnancies (OR: 3.6; 95% CI: 1.15, 11.34).
Conclusions
Manifestations of TB in pregnant women differ from those in the general population with TB. Pregnancy complicated with active TB greatly harms the mother and foetus and requires special attention in the future.
Keywords: Pregnancy, miliary tuberculosis, tuberculosis, Mycobacterium tuberculosis
Introduction
The true extent of tuberculosis (TB) during pregnancy remains uncertain; however, it is estimated that there were approximately 216,500 cases of active TB worldwide in 2011 [1]. The African region and the Southeast Asian region were identified as the regions with the highest burdens, while China and Indonesia shared the fifth position in terms of TB prevalence [1].
Active TB during pregnancy poses significant risks to both the mother and the infant [2–6]. A study revealed that the odds of antenatal admission and miscarriage were found to be nine times greater in pregnancies with active TB compared to pregnancies without active TB [2]. Furthermore, infants born to mothers with active TB exhibited a fourfold increased risk of perinatal mortality, highlighting the severity of the consequences associated with TB during pregnancy [2].
Recent studies have demonstrated an elevated risk of TB in pregnant women, including the increased risks of maternal hospitalization and death and adverse pregnancy outcomes, primarily attributed to intricate alterations in the maternal immune system [2, 7–11]. The presentation of TB during pregnancy is believed to differ from the general population, leading to worse outcomes. However, these differences have not been comprehensively described [12].
The objective of this study was to delineate the demographics, clinical characteristics and short-term outcomes of TB during pregnancy, in comparison to the general population with TB.
Methods
Study population and data collection
This retrospective cohort study enrolled patients diagnosed with active TB during pregnancy or within six months (180 days) postpartum, who were admitted to West China Hospital between 2011 and 2022. Using the Tenth Revision of the International Classification of Diseases (ICD-10) criteria set by the World Health Organization (WHO), we retrieved data on TB patients from electronic medical records (EMR). Active TB cases included both bacteriologically confirmed and clinically diagnosed cases [7]. Clinically diagnosed cases were determined by TB specialists or respiratory physicians based on a combination of medical history, clinical signs and symptoms and radiological changes suggestive of TB disease. The exclusion criteria were as follows: (1) a diagnosis of active TB before pregnancy, (2) pregnancy achieved through in vitro fertilization–embryo transfer and (3) incomplete clinical records. Pregnancy resulting from in vitro fertilization–embryo transfer was not considered due to evidence indicating that undergoing in vitro fertilization–embryo transfer poses a possible risk for serious maternal problems and unfavourable perinatal outcomes in patients with TB during pregnancy [13, 14]. In cases where a patient had multiple admissions, only data from the first admission were included. After manual screening, the remaining patients were included in the study group (pregnant group). Each case was matched with two non-pregnant/non-postpartum patients with TB (non-pregnant group) based on age, gender and year of admission time.
We extracted data for this study from medical records, which included demographics (such as age, sex and ethnicity), symptoms, comorbidities, laboratory findings, radiological presentations, diagnosis and outcome.
The study received ethical approval from the Ethics Committee of West China Hospital, Sichuan University (no. 761 (2019)) (including a waiver of informed consent). For patients whose perinatal status remained unknown at discharge, a follow-up was conducted via telephone in January 2023 and obtained informed consent.
Definitions
Factors predisposing to TB include the following: household contacts with exposure, human immunodeficiency virus (HIV) infection, diabetes mellitus, chronic renal failure/haemodialysis, silicosis, gastrectomy [15–17], jejunoileal bypass [18, 19], haematological malignancies, head or neck carcinoma, alcohol consumption and therapy with corticosteroids (prednisone or equivalent administered at a dose of >15 mg/day for ≥1 month) [20].
Pregnancy is categorized into three stages: early pregnancy (weeks 1–13), middle pregnancy (weeks 14–27) and late pregnancy (28th week until delivery).
Typical miliary TB occurs when Mycobacterium tuberculosis (MTB) spreads acutely through the lymphatic and blood systems, resulting in the formation of small tubercles that resemble millet seeds in size and appearance (multiple 1–3-mm well-defined nodules throughout all lung fields) [21,22].
The definitions of pulmonary tuberculosis (PTB), and extrapulmonary tuberculosis (EPTB) were derived from WHO guidelines [23].
Severe TB was defined as causing maternal death or admission to the intensive care unit (ICU).
Clinical outcome
The primary outcome of our study focused on maternal mortality. Secondary outcomes included severe TB and perinatal outcomes. For patients whose perinatal status remained unknown at discharge, a follow-up was conducted via telephone in January 2023.
Statistical analyses
Categorical variables were presented as frequency with percentage and compared using the Chi-square or Fisher’s exact test. Continuous variables were reported as means with standard deviation (SD) or median with interquartile range (IQR) and analysed using Student’s t-test or the Mann–Whitney U-test (based on data distribution). Univariate and multivariate logistic regression were used to identify the risk factors for severe disease. The significance level for the two-tailed p value was set at ≤.05. All statistical analysis was performed using the SPSS Version 28.0 software (IBM, Chicago, IL), which was copyrighted.
Results
Study population
From 2011 to 2022, a screening process based on the ICD-10 codes from EMR identified a total of 51,669 admitted TB patients. Among them, 123 patients with active TB were selected as the study group (pregnant group), while 246 patients were matched as the control group (non-pregnant group). The detailed flowchart is presented in Supplementary Figure 1.
Baseline characteristics and symptomatology
For baseline characteristics, all participants in the study were female and the mean age in the pregnant group was 26.63 years, while in the non-pregnant group, it was 26.69 years, with no statistically significant difference observed (p = .916). Both groups were predominantly represented by individuals of Han nationality, and there were no significant disparities between them (p = .572). Notably, household contact exposure and complications, specifically factors predisposing to TB, exhibited no statistically significant variances between the two groups, demonstrating comparability (Table 1).
Table 1.
Baseline characteristics and symptomatology of pregnant group and non-pregnant group matched by age, gender and year of admission time.
| Variables | Pregnant group (n = 123) | Non-pregnant group (n = 246) | p Value |
|---|---|---|---|
| Age (mean (SD)), years | 26.63 (4.98) | 26.69 (5.02) | .916 |
| Nationality | .572 | ||
| Han nationality (n/%) | 89 (72.4) | 171(69.5) | |
| Non-Han nationality (n/%) | 34 (27.6) | 75(30.5) | |
| Household contact expose (n/%) | 5 (4.1) | 7 (2.8) | .756 |
| Complications | |||
| HIV infection (n/%) | 0 (0) | 1 (0.4) | 1.000 |
| Chronic hepatopathy (n/%) | 9 (7.3) | 9 (3.7) | .124 |
| Diabetes mellitus (n/%) | 1 (0.8) | 1 (0.4) | 1.000 |
| Chronic renal failure (n/%) | 4 (3.3) | 6 (2.4) | .910 |
| Factors predisposing to tuberculosisa (n/%) | 12 (9.8) | 28 (11.4) | .636 |
| Symptoms | |||
| Highest temperature | <.001 | ||
| T > 38.5 °C (n/%) | 67 (54.5) | 66 (26.8) | |
| 37.3 °C ≤ T ≤ 38.5 °C (n/%) | 8 (6.5) | 20 (8.1) | |
| T < 37.3 °C (n/%) | 48 (39.0) | 160 (65.0) | |
| Constitutional symptomsb (n/%) | 26 (21.1) | 101 (41.1) | <.001 |
| Cough (n/%) | 61 (49.6) | 112 (45.5) | .461 |
| Expectoration (n/%) | 40 (32.5) | 74 (30.1) | .633 |
| Haemoptysis (n/%) | 7 (5.7) | 12 (4.9) | .739 |
| Dyspnoea (n/%) | 49 (39.9) | 46 (18.7) | <.001 |
| Chest pain (n/%) | 22 (17.9) | 64 (26.0) | .082 |
| Neurological symptomsc (n/%) | 30 (24.4) | 27 (11.0) | <.001 |
| Gastrointestinal symptomd (n/%) | 16 (13.0) | 38 (15.4) | .532 |
TB: tuberculosis; SD: standard deviation; HIV: human immunodeficiency virus; T: temperature. Bold values indicate p < .05 and are statistically significant.
Well-known factor predisposing to tuberculosis included: household contacts exposed, HIV infection, diabetes mellitus, chronic renal failure/haemodialysis, silicosis, gastrectomy, jejunoileal bypass, haematological malignancies, head or neck carcinoma, alcohol consumption and therapy with corticosteroids (prednisone or equivalent administered at >15 mg/day for ≥1 month).
Constitutional symptoms include weight loss, fatigue and/or night sweats.
Neurological symptoms include headache, disturbance of consciousness, impaired physical activity and speech disorder.
Gastrointestinal symptom include abdominal pain, diarrhoea, nausea and vomiting.
Regarding symptomatology, several noteworthy differences emerged between the pregnant group and the non-pregnant group. Among these, the natural pregnancy group exhibited higher frequencies of fever, dyspnoea and neurological symptoms, while constitutional symptoms were more prevalent in the non-pregnant group. Fever emerged as the predominant clinical manifestation in the pregnant group, accounting for 71% of total cases. The further stratified analysis revealed that cases with high fever (highest body temperature >38.5 °C) constituted 54.5% of the total cases. On the other hand, constitutional symptoms were most frequently observed in the non-pregnant group (Table 1).
Radiological and laboratory findings
Due to concerns regarding radiation exposure during pregnancy, a proportion of patients in the pregnant group declined to undergo relevant examinations. Only 86.2% of patients in this group received chest imaging, while the non-pregnant group had a higher completion rate of 96.7% for chest imaging, leading to a significant difference between the two groups (p < .001). Among the subset of individuals who underwent complete chest imaging, notable disparities were observed between the pregnant group and the non-pregnant group in terms of lung involvement. The pregnant group displayed a larger extent of lung involvement, with a higher prevalence of typical miliary TB and pleural effusion compared to the non-pregnant group. However, cavities were less frequently detected in the group of pregnant TB individuals (Table 2).
Table 2.
Radiological and laboratory findings of pregnant group and non-pregnant group matched by age, gender and year of admission time.
| Variables | Pregnant group (n = 123) | Non-pregnant group (n = 246) | p Value |
|---|---|---|---|
| Chest imagings performeda (n/%) | 106 (86.2) | 238 (96.7) | <.001 |
| Radiological findings | .036 | ||
| Bilateral pulmonary infiltratesb (n/%) | 69 (65.1) | 116 (48.7) | |
| Unilateral pulmonary infiltratesb (n/%) | 16 (15.1) | 59 (24.8) | |
| Noneb (n/%) | 21 (19.8) | 63 (26.5) | |
| Typical miliary TBb (n/%) | 26 (24.5) | 26 (10.9) | .033 |
| Cavitary infiltratesb (n/%) | 4 (3.7) | 42 (17.6) | <.001 |
| Pleural effusionb (n/%) | 52 (49.1) | 71 (29.0) | <.001 |
| Regular laboratory findings | |||
| RBC (median (IQR)), ×109/L | 3.62 (3.21, 4.06) | 4.37 (3.99, 4.71) | <.001 |
| PLT (median (IQR)), ×109/L | 264.00 (193.00, 378.00) | 249.00 (185.75, 320.00) | .075 |
| WBC (median (IQR)), ×109/L | 7.37 (5.35, 10.01) | 6.14 (5.35, 10.01) | <.001 |
| NLR (median (IQR)) | 7.71 (4.85, 12.45) | 3.29 (2.19, 5.41) | <.001 |
| CRP (median (IQR)), mg/L | 61.40 (20.92, 92.63) | 9.31 (3.95, 33.90) | <.001 |
| Serum albumin (median (IQR)), g/L | 31.20 (27.30, 35.80) | 40.40 (35.80, 43.40) | <.001 |
| Immunological tests for tuberculosis | |||
| IGRA positivec (n/%) | 48/68 (70.6) | 89/111 (80.2) | .142 |
| TST positived (n/%) | 51/86 (59.3) | 122/158 (77.2) | .003 |
| TB antibodye (n/%) | 19/65 (29.2) | 51/115 (44.3) | .046 |
TB: tuberculosis; IQR: interquartile range; RBC: red blood count; WBC: white blood count; PLT: platelets count; NLR: neutrophil-to-lymphocyte ratio; CRP: C-reactive protein; IGRA: interferon gamma release assay; TST: tuberculin skin test. Bold values indicate p < .05 and are statistically significant.
Chest imagings including X-ray, computed tomography and magnetic resonance imaging.
Among those with chest imagings performed.
Among those with IGRA performed.
Among those with TST performed.
Among those with TB antibody performed.
In terms of routine laboratory investigations, the pregnant group exhibited lower levels of red blood cell (RBC) count and albumin compared to the non-pregnant group. Conversely, the white blood cell (WBC) count, neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) levels were higher in the pregnant group as compared to the non-pregnant group. Regarding auxiliary diagnostic immunological tests for TB, including the tuberculosis interferon-gamma release assay (TB-IGRA), tuberculin skin test (TST) and TB antibodies, both the pregnant group and non-pregnant group demonstrated the highest sensitivity with TB-IGRA, followed by the TST, while TB antibodies displayed the lowest sensitivity (Table 2).
Diagnosis
The distribution of TB between the pregnant group and the non-pregnant group showed similar proportions of PTB, with 82.9% and 77.6%, respectively, and no statistically significant difference was observed (p = .237). However, when considering EPTB, notable differences emerged. Lymphatic TB was the most common form in the non-pregnant group, while tuberculous pleuritis and tuberculous meningitis predominated in the pregnant group (Figure 1(A)). In our study, the pregnant group had a shorter median time from symptom onset to diagnosis compared to the non-pregnant group. Although there was no statistically significant difference in the utilization of invasive diagnostic procedures between the two groups, it is important to note that the pregnant group still had a lower rate of bacteriologic confirmation compared to the non-pregnant group (Supplementary Table S1).
Figure 1.
Information related to TB diagnosis. (A) The specific distribution of TB between the pregnant group and the non-pregnant group (*p < .05, **p < .01); (B) Onset time distribution of the pregnant group.
In the pregnant group, 48.8% of patients experienced TB-related clinical symptoms during the middle stage of pregnancy, as indicated by the detailed distribution provided in Figure 1(B).
Outcome
Within the pregnant group, the rate of ICU admission for pregnant women was 16.3%, a substantial increase compared to the rate of 0.8% observed in the non-pregnant group. Moreover, the TB-related mortality rate stood at 3.3% in the pregnant group, while no deaths were reported in the non-pregnant group. These findings highlight a heightened susceptibility of pregnant women with TB to ICU admission and TB-related mortality, with a statistically significant disparity between the two groups (p < .05) (Table 3). According to epidemiological investigations, Sichuan Province has experienced a significant decrease in maternal mortality, declining from 37.16 per 100,000 in 2011 to 13.09 per 100,000 in 2022 [24,25]. However, in our study, when compared to the lowest maternal mortality rates recorded in 2022, our rates were considerably higher than the average.
Table 3.
Outcome of pregnant group and non-pregnant group matched by age, gender and year of admission time.
| Variables | Pregnant group (n = 123) | Non-pregnant group (n = 246) | p Value |
|---|---|---|---|
| Maternal outcome | |||
| TB-related mortality (n/%) | 4 (3.3) | 0 (0) | .012 |
| Admission to the ICU (n/%) | 20 (16.3) | 2 (0.8) | <.001 |
| Perinatal outcome | |||
| Spontaneous miscarriage (n/%) | 42a (34.1) | ||
| Induced abortion (n/%) | 29b (23.6) | ||
| Preterm birth (n/%) | 5 (4.1) | ||
| Normal delivery (n/%) | 47 (38.2) |
TB: tuberculosis. Bold values indicate p < .05 and are statistically significant.
Among them, 18 experienced a spontaneous miscarriage in early pregnancy, 23 in mid-pregnancy and one in late pregnancy.
Among them, 24 had an abortion because of concerns about tuberculosis or drug side effects on the foetus, and only five had an abortion because of inevitable abortion.
In the pregnant group, perinatal outcomes raised significant concerns, particularly due to a markedly elevated spontaneous miscarriage rate of 34.1%. Examination of gestational age distribution revealed that 18 miscarriages occurred during early pregnancy, constituting 64.3% of the total in this stage. For mid-pregnancy, 23 miscarriages were observed, accounting for 38.3% of the total in this phase. Late pregnancy witnessed one miscarriage, representing 5.3% of the total occurrences in this trimester. TB in early pregnancy has a great adverse impact on the foetus. Induced abortions constituted 23.6% of the overall cases. Moreover, the preterm birth rate was 4.1%, while normal deliveries occurred in 38.2% of cases. Among the 29 cases where induced abortion was chosen, 24 individuals (19.5% of the total) made this decision due to concerns regarding the potential impact of TB or medication side effects on the foetus. Only five individuals opted for induced abortion due to unavoidable miscarriage. These findings underscore the complex and challenging perinatal outcomes in the context of TB during pregnancies (Table 3).
Then, we conducted an exploratory comparison of outcomes among pregnant women with bacteriologically and clinically diagnosed TB. In the initial assessment, no statistically significant differences were observed at baseline (age, nationality and Charlson score) between the bacteriologically confirmed TB group and the clinically diagnosed TB group, indicating comparability. No statistically significant distinctions emerged when evaluating TB-related maternal mortality and perinatal outcomes between the two groups (Supplementary Table S2).
Risk factors for severe pregnant group
The severe pregnant group was defined pregnant women who required ICU admission for supportive treatment or died. Among the study participants, 20 individuals were classified as severe TB, while 103 were categorized as non-severe TB. Utilizing univariate logistic regression analysis, we examined potential risk factors and identified statistically significant associations (p < .05) with haemoglobin levels, WBC counts and typical miliary TB on imaging (Supplementary Table S3). The three variables were subsequently included in a multivariate logistic regression analysis. In this analysis, only the presence of typical miliary TB on imaging remained significantly associated as an independent risk factor for the severe pregnant group (OR: 3.6; 95% CI: 1.15, 11.34) (Table 4).
Table 4.
Multiple logistic regression analysis of risk factors for severe pregnant group.
| Risk factors | OR (95% CI) | p Value |
|---|---|---|
| Haemoglobin | 0.99 (0.95, 1.02) | .396 |
| WBC | 1.15 (0.98, 1.34) | 1.114 |
| Typical miliary TB | 3.60 (1.15, 11.34) | .028 |
TB: tuberculosis; OR: odds ratio; CI: confidence interval; WBC: white blood count. Bold values indicate p < .05 and are statistically significant.
Discussion
In our study, we sought to compare patients hospitalized with pregnancy-related active TB to the hospitalized general population with active TB spanning the years 2011–2022. Our analysis revealed significant differences across various parameters between the two groups, including clinical manifestations, laboratory findings, imaging characteristics and outcomes. Pregnancy-related TB displayed more typical clinical presentations, such as fever, dyspnoea and neurological symptoms, with a higher prevalence of miliary TB. Pregnant patients displayed significantly lower RBC and albumin counts, coupled with elevated levels of inflammatory markers. This suggested a more pronounced inflammatory response and poorer nutritional status in the pregnancy group. Throughout the hospitalization period, pregnant patients with TB experienced notably higher rates of ICU admission and TB-related mortality compared to their non-pregnant counterparts. In conclusion, considering all these observed differences, our study indicated that pregnancy might contribute to the dissemination and exacerbation of TB. Besides, it is noteworthy that the spontaneous abortion rate in pregnancies complicated by active TB is as high as 34.1%, particularly in early pregnancy when the rate is the highest. Additionally, apart from the high spontaneous abortion rate, our study revealed that 19.5% of pregnant women opted for induced abortion due to concerns about TB and the potential adverse effects of anti-TB drugs. Finally, we found the sole independent predictor of severe TB cases in pregnancies was the presence of typical miliary TB findings on imaging (OR: 3.6; 95% CI: 1.15, 11.34).
Our study indicated that pregnancy may contribute to the dissemination and exacerbation of TB, which contradicts the findings of a recent large-scale case-control study [9]. The discrepancy in results may be attributed to variations in the definitions of TB exacerbations used in our respective studies. The case-control study defined severe TB solely based on the presence of at least two criteria, such as multi-organ involvement, positive culture results or hospitalization exceeding 10 days. According to their findings, pregnancy was not identified as a contributing factor to the exacerbation of TB. However, it is important to note that their definition of severe TB was overly broad and incomplete. In contrast, our study utilized more specific and comprehensive clinical data obtained from healthcare institutions. This allowed us to thoroughly examine the impact of pregnancy on TB from multiple perspectives, thereby enhancing the credibility of our findings.
Pregnancy can contribute to the worsening and spread of TB, which may be mediated by changes in immune function caused by hormone fluctuations during pregnancy [26–31]. Compared to the non-pregnant group, the pregnant group exhibited a significant decrease in positive rates of TST and TB antibodies (p < .05), which also reflected the effect of pregnancy on immune function [21]. During pregnancy, levels of oestrogen and progesterone significantly increase. Those sex hormones can lead to a decrease in type 1 helper T cell (Th1) mediated immune responses and CD4+ T cell proliferation [32,33]. Interferon-gamma (IFN-γ), an important cytokine involved in controlling the infection and spread of MTB, plays a role in granuloma formation and the generation of reactive oxygen species. Its secretion depends on Th1 cells. Therefore, during pregnancy, a decrease in IFN-γ secretion is observed due to the impact on Th1, which contributes to an increased susceptibility to MTB infection and dissemination [26–29,34,35].
The possibility of TB should be considered when clinical symptoms such as fever occur during pregnancy in areas where TB is endemic. The imaging and immunological and etiological examinations of TB should be completed. According to the current guidelines, the radiation exposure dose of X-ray and CT examination is much lower than the exposure dose associated with foetal injury, and pregnant women should be encouraged to receive necessary imaging examinations, because the risk of misdiagnosis and delayed diagnosis is much higher than the risk of radiation [36]. Compared with TST and TB antibodies, TB-IGRA demonstrated higher sensitivity during pregnancy in TB-endemic countries, consistent with previous studies [37–39].
In our study, out of the 123 individuals with pregnant-related TB, 24 individuals (19.5%) opted for induced abortion due to concerns about the potential impact of TB or drug side effects on the foetus. Current research indicates that untreated TB can have significant effects on pregnant women and their unborn babies. If the patient was contracting TB, anti-TB treatment should be initiated [40–42]. With proper treatment, pregnant women with TB disease can have successful outcomes [43]. For drug-sensitive TB, a standard four-drug regimen is recommended, including isoniazid (INH), rifampicin (RIF), pyrazinamide (PZA) and ethambutol (EMB) [44,45]. Although there is currently a lack of high-quality safety studies on PZA in pregnant women, potential risks cannot be completely ruled out [46]. Therefore, the use of PZA should be decided on a case-by-case basis, taking into consideration the patient’s preferences and the severity of the disease. However, INH, RIF and EMB are generally considered to be relatively safe [47]. For diagnosed and treated TB cases with relatively safe medications, overly aggressive measures such as induced abortion may not be necessary. TB specialists or infectious disease physicians should strengthen patient education and actively monitor for drug-related adverse effects.
Limitations and recommendations
Our study is subject to several limitations that should be acknowledged. First, it is a study conducted at a single centre, which may restrict the generalizability of our findings to other populations or settings. As a retrospective study, patient characteristics were retrieved from the hospital’s database, resulting in potential bias due to loss of data variable capture and shifting of recall. Secondly, there is a potential for selection bias as our analysis focused solely on hospitalized patients, which may not represent the entire spectrum of pregnancy-related TB cases. It may also overestimate foetal and maternal mortality. Thirdly, the study duration spans a 10-year period, during which there have been substantial advancements in disease management practices, data collection methodologies and socioeconomic factors. For instance, the implementation of TB-IGRA testing in our hospital was initiated only in 2012, leading to some missing data. Nevertheless, we made efforts to minimize this bias through meticulous matching of patients based on their admission time. Lastly, our study lacks data on the incidence of pregnancy-related TB, the prevalence of latent TB infection before pregnancy and foetal mortality with normal pregnancy cases in our hospital or region. It is challenging to distinguish between reactivation of latent TB or new infections as the cause of newly diagnosed active TB cases. Furthermore, the impact of active TB during pregnancy on foetal outcomes could not be comprehensively evaluated. To address these limitations, future research endeavours should aim for multicentre prospective study designs with standardized data collection protocols. Place the screening and comprehensive management of TB in women of childbearing age on the agenda.
Conclusions
In summary, patients with TB related to pregnancy exhibit more severe manifestations and worse prognosis than the general population. Pregnancy complicated with active TB greatly is harmful to the mother and foetus, it is imperative to prioritize and enhance screening and prevention efforts in this unique population to minimize maternal and child health impact.
Supplementary Material
Funding Statement
No funding was received to assist with the preparation of this manuscript.
Author contributions
Jiayu Wen: article design, data collection, writing. Jian-Qing He: article design, project administration, writing – review and editing.
Ethical approval
The study received ethical approval from the Ethics Committee of West China Hospital, Sichuan University [No. 761 (2019)]. For patients whose perinatal status remained unknown at discharge, a follow-up was conducted via telephone in January 2023 and obtained informed consent. The procedures used in this study adhere to the tenets of the Declaration of Helsinki.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Data availability statement
The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Data Availability Statement
The datasets used and/or analysed during the current study are available from the corresponding author upon reasonable request.