Characteristics of the pregnancy and labour course in women who underwent COVID-19 during pregnancy

Introduction

Studying the impact of COVID-19 on pregnancy and childbirth is a valuable area of research in the context of the past pandemic. The pandemic highlighted the need for a thorough understanding of the mechanisms by which the virus affects pregnant women and birth outcomes, and the need to develop effective management and prevention strategies to minimise risks to mother and child. Pregnancy has been found to increase the risk of severe COVID-19, which in turn can adversely affect pregnancy and birth outcomes, increasing the likelihood of preterm birth and the need to hospitalise new-borns in the intensive care unit.

A number of studies have concentrated on the consequences for pregnant women infected with the COVID-19, which causes the disease known as coronavirus disease 2019. For example, Zhurabekova et al. [1] reported that approximately 40 cases of maternal mortality were associated with COVID-19, underscoring the critical nature of the disease in pregnancy. The findings indicated the potential for severe complications, including preterm labour and stillbirth. Similarly, Zhurmetova et al. [2] documented the association between COVID-19 and preterm labour, stillbirths, and complications such as pre-eclampsia. These studies provide an initial understanding of the risks, but often lack detailed analysis of the relationships between infection and maternal and neonatal health parameters.

Further research by Kyzdarbekova and Turgyn [3] concentrated on the elevated risks confronted by pregnant women with pre-existing respiratory conditions, such as asthma or COPD. The study indicated that inadequate management of these comorbidities in the pre-hospital stage could potentially exacerbate complications during pregnancy. Furthermore, Karimsakova and Abenova [4] discovered that 22 % of the pregnant women in their cohort developed pneumonia as a result of contracting the virus, thereby significantly increasing the risk of adverse outcomes, including severe maternal complications.

Notwithstanding these findings, there remain gaps in the understanding of the impact of the COVID-19 on various clinical parameters, including blood gas levels, hematocrit, and liver enzyme activity. Penna et al. [5] have called for a global analysis of the impact of the COVID-19 on maternal and foetal health, and have urged the development of strategies to manage pregnancy during future pandemics. However, the study did not investigate the potential correlation between maternal and foetal outcomes, which represents a topic for further research.

The lack of comprehensive analyses of the impact of coronavirus infection on various blood parameters in pregnant women is noteworthy. Monitoring changes in blood counts may be key to assessing maternal and foetal health, especially in the context of the threat posed by COVID-19 [6]. The circulatory system serves as an important indicator of both the acute inflammatory process and long-term changes caused by infection [7]. Moreover, the studies reviewed did not investigate the correlative relationship between foetal and maternal outcomes and the presence of coronavirus infection. This leaves a significant gap in understanding how viral load, duration of illness and severity of symptoms may influence the risk of complications during pregnancy and postpartum.

This research offers a comprehensive analysis of the relationship between the SARS-CoV-2 virus and key clinical and laboratory parameters during pregnancy, with a particular focus on gas exchange disorders, liver enzyme abnormalities, and electrolyte imbalances. This represents a significant departure from previous studies in this field. Moreover, the study investigates the impact of these physiological disturbances on maternal and neonatal health, identifying risk factors such as preterm labour, stillbirth, and postpartum haemorrhage. Furthermore, this work offers detailed insight into the impact of infection severity and timing (first, second, or third trimester) on pregnancy outcomes, thus contributing to the ongoing efforts to enhance maternal care protocols in the event of future pandemics.

The study aims to analyse the characteristics of pregnancy and delivery in women who have had COVID-19 during pregnancy. The impact of a COVID-19 infection on key pregnancy outcomes, including birth weight, preterm birth rates, and the need for hospitalisation, will be examined. Furthermore, the relationships between infection and clinical and laboratory parameters, such as blood gas levels, electrolyte balance, and liver function, will be explored. Furthermore, the study aims to ascertain the risks of pregnancy complications, such as preeclampsia, stillbirth, and postpartum haemorrhage, associated with COVID-19 infection. The ultimate objective is to develop strategies to enhance the care of pregnant women in the context of emerging variants of the virus.

Materials and methods

The study was conducted in the Communal State Enterprise on the right of economic management Municipal Maternity Hospital No. 1. Pregnant women divided into two groups were included in the prospective study. Group I consisted of 60 pregnant women who underwent COVID-19 during pregnancy. The average age of the participants in this group was 28.5 ± 4.2 years. Of these, 40 (66.7 %) were first-time mothers and 20 (33.3 %) were had second or more pregnancies. The average gestational age at inclusion in the study was 32.7 ± 3.1 weeks. Group II (control group) included 60 healthy pregnant women comparable in age, parity and gestational age to group I. The mean age of the control group participants was 27.9 ± 4.6 years, of whom 38 (63.3 %) were first-time mothers and 22 (36.7 %) were had second or more pregnancies. The average gestational age at study inclusion in group II was 33.1 ± 2.8 weeks.

Inclusion criteria for both groups were singleton pregnancy, gestational age between 28 and 40 weeks, absence of severe extragenital diseases (e.g. cardiovascular, renal, endocrine, etc.) and informed consent to participate in the study. Exclusion criteria were multiparity pregnancy, severe extragenital diseases and refusal to participate in the study. All participants underwent general clinical examination methods, including anamnesis collection, physical examination, and anthropometric data measurement (height, weight, body mass index). Obstetric methods were also performed: examination, measurement of blood pressure, uterine fundus height, determination of foetal position, listening to the foetal heartbeat, and assessment of cervical maturity according to the Bishop scale. Laboratory methods included general blood and urine analysis, blood biochemical examination (determination of glucose, urea, creatinine, total protein, albumin, transaminases, bilirubin, creatine phosphokinase (CPK), ferritin, lactate dehydrogenase (LDH), coagulogram (prothrombin time, activated partial thromboplastin time, fibrinogen, D-dimer). To exclude tuberculosis, sputum microkinesis tests (MCT) were additionally taken.

The pulse oximetry method with the determination of blood oxygen saturation level was used to diagnose hypoxaemic disorders of gas exchange. The feto-placental system and the intrauterine foetus were assessed using Dopplerometric studies (blood flow in uterine arteries, umbilical artery, and middle cerebral artery of the foetus) and cardiotocography to detect signs of intrauterine foetal hypoxia. Chest radiography in two projections and computer tomography of the chest organs were performed. All pregnant women were examined by a general practitioner, an infectious disease specialist, and a phthisiatrician as required. All pregnant women who had COVID-19 (group I) were divided into subgroups according to the severity of the infection: mild (no pneumonia), moderate (pneumonia without respiratory failure) and severe (pneumonia with respiratory failure requiring oxygen therapy or respiratory support). The timing of the infection was also factored in: first trimester of pregnancy, second trimester of pregnancy, or third trimester of pregnancy. This provided a more detailed analysis of the effect of COVID-19 on pregnancy, labour and new-borns depending on the severity of the disease and gestational age.

The data were collected and analysed using modern statistical methods of information processing, including descriptive statistics, methods of assessing the reliability of differences between groups (Student’s test, Mann-Whitney test, chi-square test), correlation and regression analysis to identify risk factors for the development of complications. Relative and absolute frequencies were calculated for qualitative data, and arithmetic mean and standard deviation were calculated for quantitative data. Correlation analysis was used to study the relationship between different indicators, and regression analysis was used to build prognostic models.

The significance of differences between groups was assessed at a significance level of p<0.05. If significant deviations from the normal course of pregnancy, labour or newborn condition were detected, appropriate treatment and correction were carried out according to existing clinical recommendations. A comprehensive approach using clinical, laboratory and instrumental methods of research, as well as detailed statistical analysis, allowed us to comprehensively study the impact of COVID-19 on the course of pregnancy, labour and newborn condition, identify risk factors for complications and develop optimal tactics for the management of pregnant women with COVID-19.

All procedures performed in the study were in accordance with the ethical standards of the Institutional Research Committee and with the 1964 Helsinki Declaration and its later amendments.

Results

Discussion

The study reviewed the peculiarities of the course of pregnancy and labour in women who underwent COVID-19 during pregnancy. The results of the studies allow us to draw several important conclusions and emphasise some significant aspects. The first important aspect is the identification of potential risks for pregnant women infected with SARS-CoV-2. Studies show that this category of women may be at increased risk of developing severe forms of COVID-19, with possible negative consequences for maternal and foetal health.

Wang et al. [11] concluded that COVID-19 infection significantly increases the risk of several adverse pregnancy outcomes, including preterm labour (OR=1.66, 95 % CI=1.41–1.96), stillbirth (OR=1.98, 95 % CI=1.22–3.21), pre-eclampsia (OR=1.46, 95 % CI=1.18–1.8) and premature rupture of amniotic fluid (PROM) (OR=1.39, 95 % CI=1.07–1.81). These correlations were also found in this study.

Wei et al. [12] also confirm that COVID-19 during pregnancy can increase the risk of complications such as pre-eclampsia (OR=1.33, 95 % CI=1.03–1.73), preterm labour (OR=1.82, 95 % CI=1.38–2.39) and stillbirth (OR=2.11, 95 % CI=1.14–3.9). This is supported by statistical data showing a significant increase in the relative risk for these conditions in pregnant women with COVID-19 compared to uninfected women. Severe forms of COVID-19 in pregnant women have even more serious consequences. Statistics show that a severe course of the disease is associated with a higher risk of pre-eclampsia, preterm labour, gestational diabetes and premature birth weight. However, a meta-analysis by Dubey et al. [13] determined that preterm birth and mean length of hospitalisation were higher in Asian studies. However, there was a reduction in the use of most therapies over time, as well as an improvement in COVID-19 outcomes in pregnant women. This emphasises the fact that the Asian population has a better tolerance to coronavirus infection than the European population, which is in line with the results of this study, where no strong correlation was found between major complications in this group of patients and coronavirus infection.

It is worth discussing the impact of COVID-19 on pregnancy and birth outcomes. Studies show that infected women may have an increased risk of complications such as preterm labour, birth hypoxia and other complications for both mother and foetus. This highlights the need for specialised medical surveillance and timely intervention to prevent complications. A systematic review by Lassi et al. [14] shows an increased risk of severe COVID-19 and adverse pregnancy and perinatal outcomes in pregnant women with certain comorbidities. The highest risk was observed in women over 35 years of age, obese, smokers, diabetics and pre-eclampsia. An increased number of preterm births was also observed among women with severe COVID-19 [15]. These findings may be useful in shaping and updating current guidelines for the management of pregnancy during seasonal outbreaks of coronavirus infection or when new resistant strains emerge. This study also found this correlation, as women older than 25 years of age in the study group had a higher risk of adverse outcomes than the younger pregnant group.

Chmielewska et al. [16] determined that the COVID-19 pandemic resulted in worse global maternal and foetal outcomes, including increased maternal mortality, stillbirths, increased risk of ectopic pregnancy and postpartum depression. There was also a correlation between foetal distress and decreased foetal weight, which is indirectly comparable to the findings in this meta-analysis. Du et al. [17] revealed that during the COVID-2019 pandemic, pregnant women were more likely to be late in pregnancy, have impaired gestational weight gain, and are more likely to have a family history of chronic disease, compared to women before the pandemic. In addition, after adjusting for other risk factors, there was an 11 and 14 % increase in the likelihood of early premature rupture of the foetal membranes and foetal distress, respectively, which is consistent with the findings in this study.

A third important aspect is the impact of COVID-19 on the health of new-borns. Numerous studies show that babies born to mothers with COVID-19 may have an increased risk of developing various adaptive disorders, such as respiratory problems and low birth weight. This emphasises the importance of long-term medical follow-up of new-borns and appropriate interventions to ensure their health and well-being. In addition, the possible long-term effects of COVID-19 infection on the mother and fetus should be addressed.

Wong et al. [18] indicate that the presence of large amounts of ACE-2 on the surface of placental cells, especially on syncytiotrophoblasts, may facilitate maternal-foetal transmission via the vertical route after COVID-19 infection. Although the virus is found in the placenta, few new-borns show symptoms of the disease. It remains a mystery how the placental barrier protects new-borns from viral infection and prevents its spread. The risk of vertical transmission of SARS-CoV-2 from mother to neonate is low with various postpartum care practices, birth during a pandemic may entail a developmental risk for the next generation. Critical long-term follow-up is needed to assess the impact of SARS-CoV-2 exposure and the COVID-19 pandemic on children’s long-term development [19], 20].

Although most studies focus on complications during pregnancy and labour, it is important to consider effects in the long term, such as the impact on child development in the later years of life and possible medical problems in the mother. Randad et al. [21] described 2 cases of respiratory failure in new-borns with a confirmed diagnosis of COVID-19, proving the negative effects on new-borns. Vimercati et al. [22] found that premature new-borns of mothers infected with COVID-19 have a higher risk of developing complications such as respiratory distress syndrome. Severe COVID-19 in the mother can worsen obstetric and neonatal outcomes, including an increased incidence of preterm labour and the need for emergency caesarean sections [23], 24]. The same trend towards impaired respiratory function in neonates was identified in the analyses of the data from this study, which is consistent with the findings described.

The role of preventive measures and vaccination should be emphasised. The introduction of the COVID-19 vaccine for pregnant women can significantly reduce the risk of infection and thus reduce the likelihood of adverse maternal and foetal outcomes. Brinkley et al. [25] demonstrated that pregnant women who received the COVID-19 vaccine in the US experienced acute side effects similar to non-pregnant women of similar age, with fewer overall side effects and less impact on work and self-care. These data provide further evidence for the safety and tolerability of COVID-19 vaccines for pregnant women. According to Watanabe et al. [26], COVID-19 vaccine administration during pregnancy was associated with a decreased likelihood of maternal SARS-CoV-2 infection (odds ratio, OR, was 0.46; 95 % CI=0.22–0.93), while there was no increase in the risk of caesarean section (OR=1.05; 95 % CI=0.93–1.2), postpartum haemorrhage (OR=0.95; 95 % CI=0.83–1.07) and inflammation of the foetal membranes and amniotic fluid (chorioamnionitis) (OR=0.95; 95 % CI=0.83–1.07).

However, further research is needed to more fully understand the efficacy and safety of vaccination for pregnant women [27], 28]. Thus, this discussion highlights the need for a comprehensive approach to the management of pregnancy and labour in COVID-19-exposed women and the importance of further research in this area to develop effective strategies to prevent and manage potential complications. The issue of the best methods of medical intervention and support for this vulnerable category of patients remains open, which requires further research and the development of clinical guidelines.

Conclusions

The study of the peculiarities of the course of pregnancy and labour in women who had COVID-19 during pregnancy allowed us to draw several important conclusions. First of all, the results indicate that COVID-19 coronavirus infection poses a serious threat to pregnant women and their future children. Multivariate analysis demonstrated a significant increase in the risk of complications such as preterm labour, stillbirth, pre-eclampsia and foetal distress in infected pregnant women. In addition, the data showed a negative impact of COVID-19 on neonatal health. COVID-19 has been shown to adversely affect neonatal weight, increasing the risk of low birth weight, respiratory distress and the need for hospitalisation in the NICU. The presence of comorbidities such as cardiovascular disease, diabetes, obesity, thrombophilia and chronic respiratory disease exacerbates the impact of infection on pregnancy and birth outcomes, significantly increasing the risk of complications.

Significant correlations were found between the presence of COVID-19 and changes in a range of physiological parameters, including levels of carbon dioxide, oxygen, blood pH, haematocrit, ferritin and liver enzymes, indicating potential gas exchange disorders, inflammatory processes and metabolic disorders. Thus, the results of the study emphasise the need for a comprehensive approach to the management of pregnancy and delivery in women with COVID-19, including careful maternal and foetal monitoring, timely detection and treatment of complications, and the development of effective prevention and risk management strategies.

Further research should focus on the need to implement longitudinal studies to systematically monitor the health of mothers and their children throughout pregnancy, labour and postnatal development. The implementation of comparative studies between groups exposed to the infection during pregnancy and those who were not exposed to the virus will reveal the specificity of risks and outcomes associated with the disease.

It is important to acknowledge the limitations of this study. Firstly, the sample size is relatively small, which may limit the generalisability of the findings to a broader population. Secondly, although significant correlations between COVID-19 infection and pregnancy outcomes were identified, the study design does not allow for the establishment of direct causality. Moreover, the focus on a single geographical location may lead to the confounding of results due to variations in healthcare systems and access to care across different regions. In conclusion, the ever-changing nature of the COVID-19 virus, including the emergence of new variants, means that the findings of this study may not be fully applicable to future strains of the virus. This highlights the necessity for continued research in this area.