1. Background
The recent outbreak of a novel human Coronavirus (COVID-19), which is called severe acute respiratory syndrome Coronavirus 2 (SARS-nCoV-2) and is growing rapidly with human-to-human transmission, has led to public concern about this pandemic (1). Clinical symptoms of COVID-19 infection in serious cases can manifest as severe pneumonia, acute respiratory distress syndrome, various organ failure, and even mortality. In contrast, in non-severe cases, it can be an asymptomatic condition or normal symptoms of respiratory system infection (1, 2). Pregnant women are affected by COVID-19 infection, both during and after pregnancy, with potential side effects (3). Therefore, determining the prevalence, risk factors, clinical symptoms, and consequences of pregnancy are the most important factors for planning the care and clinical management of the mother (4).
Physiological changes occur during pregnancy to reduce anti-inflammatory immune responses to prevent fetal rejection, making women more vulnerable to severe diseases after exposure to viruses, especially respiratory viruses (5). Studies have shown that COVID-19 infection during pregnancy may cause adverse pregnancy outcomes, including preterm birth, maternal mortality, neonatal intensive care unit (NICU) admission, and death. Therefore, there are concerns about the serious consequences of the COVID-19 epidemic for pregnant women and babies (6).
2. Objectives
According to the materials mentioned above and the importance of the impact of COVID-19 infection on the health of pregnant women and infants as a high-risk group, the present study was conducted with the aim of determining the effect of COVID-19 infection on pregnant women and their infants. This study aimed to determine maternal and neonatal complications and consequences related to COVID-19 infection.
3. Methods
3.1. Study Setting
This case-control study was conducted on pregnant women with COVID-19 infection between February 2021 and February 2022. The inclusion criteria were women aged between 15 - 45 years being infected with COVID-19 during pregnancy based on laboratory (positive polymerase chain reaction (PCR) test) and imaging findings. Indeed, only hospitalized women with moderate to severe disease were included. The exclusion criteria were the underlying chronic diseases such as heart and liver failure or end-stage renal disease (ESRD). Also, patients with a history of previous infection with COVID-19 (before pregnancy) were excluded from the study. At the same time, the pregnant women who had no evidence of COVID-19 infection were entered as a control group. The case and control group patients were matched in terms of age and other demographic and anthropometric information.
3.2. Ethical Consideration
The Alborz University of Medical Sciences Ethical Committee gave its approval to this experiment (IR.ABZUMS.REC.1400.332), and informed consent was obtained from patients prior to their enrolment.
3.3. Initial Evaluation and Follow-up
A questionnaire was designed to obtain demographic and obstetric information such as age, body mass index (BMI), gravida, current and past medical histories, as well as pregnancy outcomes such as abortion, preterm delivery, stillbirth, preeclampsia, gestational diabetes mellitus, and type of delivery. In pregnancy with COVID-19 infection, the duration of hospitalization, the severity of the disease, lung involvement by chest CT scan, and admission to the intensive care unit (ICU) were evaluated and recorded. Indeed, the participants were followed up until delivery and 6 months post-partum, and the neonatal outcomes such as admission to the neonatal intensive care unit, low birth weight, intrauterine growth restriction, and hearing defect of the neonates were collected. All data were gathered and compared between groups.
3.4. Statistical Analysis
All data were analyzed using IBM’s SPSS statistics (Statistical Package for Version 20). Fisher’s exact testing and chi-square analysis were employed to establish the association. To compare the outcomes of the pregnancy in two groups, an independent t-test was performed. A P-value < 0.05 was used to determine statistical significance.
4. Results
A total of 300 pregnant women with COVID-19 infection who were hospitalized and 300 healthy pregnant women as controls were included in the study. The characteristics of the participants are summarized in Table 1. The most common underlying diseases in pregnant women with COVID-19 and the control group were cardiovascular diseases (3.3% and 4.3%), hypothyroidism (3% and 4%) and diabetes (2.7% and 3%), respectively. There was no statistically significant difference between the two groups in terms of underlying diseases (P > 0.05) (Table 1).
Table 1.Comparison of the Characteristics of the Participants in the Case and Control Groups a
| Variables | Case | Control | P-Value |
|---|---|---|---|
| Age, y | 31.35 ± 3.2 | 28.86 ± 3.5 | 0.07 |
| Gestational age, week | 29.4 ± 1.8 | 28 ± 1.6 | 0.23 |
| Gravidity, | 0.54 | ||
| 1 | 76 (25.3) | 92 (30.6) | |
| 2 | 114 (38) | 129 (43) | |
| 2 > | 110 (36.6) | 79 (26.3) | |
| Parity | 0.79 | ||
| Nulliparous | 106 (35.3) | 125 (41.6) | |
| Multiparous | 194 (64.6) | 175 (58.3) | |
| Past medical history | |||
| History of abortion | 34 (11.3) | 31 (10.3) | 0.89 |
| Hypothyroidism | 9 (3) | 12 (4) | 0.50 |
| Cardiovascular disease | 10 (3.3) | 13 (4.3) | 0.38 |
| Gestational diabetes mellitus | 8 (2.7) | 9 (3) | 1.00 |
aValues are expressed as mean ± SD or No. (%).
In the case group, the mean hospital stay among pregnant women with COVID-19 infection was 4.59 ± 1.2 days. 78.3% of patients suffered from moderate disease severity, and 21.7% of them suffered from severe disease. It was also found that 56.3% of patients had no significant lung involvement in chest CT, while mild, moderate, and severe lung involvement in this group was 28.7%, 14.7%, and 2%, respectively. Finally, 22.3% of these patients were admitted to the intensive care unit.
The maternal and neonatal outcomes of the studied patients are listed in Table 2. The results showed that the frequency of cesarean delivery in patients with COVID-19 was 38%, while this rate was 20% in the control group. This difference was significant and significant (P = 0.001). It was also found that pregnant women suffering from COVID-19 had significantly more preterm labor (P = 0.01). Babies born to mothers infected with COVID-19 had a significantly higher hospitalization rate in the intensive care unit than the control group (P = 0.001). Other maternal and neonatal complications were not significantly different between the two groups.
Table 2.Maternal and Neonatal Outcomes of Pregnant Women with COVID-19 and Control Group a
| Variables | Case | Control | P-Value b | CI95% |
|---|---|---|---|---|
| Maternal outcomes | ||||
| Cesarean section | 114 (38) | 60 (20) | 0.001 | 1.3 - 2.03 |
| Vaginal delivery | 186 (62) | 240 (80) | 0.01 | 1.2 - 2.5 |
| Preterm labor | 42 (14) | 31 (10.3) | 0.01 | 0.6 - 1.6 |
| Gestational diabetes mellitus | 25 (8.3) | 31 (10.3) | 0.4 | 0.8 - 1.5 |
| Preeclapsia | 19 (6.3) | 21 (7) | 0.7 | 0.75 - 1.4 |
| Neonatal outcomes | ||||
| Intrauterine growth restriction | 25 (8.3) | 22 (7.3) | 0.6 | 0.47 - 1.58 |
| Admission to the intensive care unit | 31 (10.3) | 11 (3.6) | 0.001 | 1.03 - 3.01 |
| Hearing defect | 3 (1) | 2 (0.7) | 0.6 | 0.4 - 1.7 |
| Stillbirth | 16 (5) | 12 (4) | 0. 39 | 0.95 - 2.44 |
| Low birth weight | 49 (16.3) | 42 (14) | 0.4 | 0.7 - 1.12 |
z Abbreviation: CI, confidence interval.
aValues are expressed as No. (%).
b P-value < 0.05 was considered significant.
5. Discussion
Pregnant women with COVID-19 infection can be at an increased risk of adverse maternal and pregnancy outcomes. It seems pregnant women are more susceptible to respiratory pathogens and pneumonia due to their immunosuppressive status and physiological differences that often lead to severe hypoxia. Therefore, it is expected that COVID-19 infection during pregnancy increases the risk of maternal and fetal complications, and therefore, women with severe pneumonia are more at risk of adverse pregnancy outcomes. However, the results of different studies on the severity of the disease and adverse pregnancy outcomes in pregnant women with COVID-19 are different (7).
The most common complications reported in the studied pregnant women include the need for emergency cesarean section in the third trimester and premature delivery (8, 9). Also, Karacam et al. reported that complications such as premature delivery, the need for cesarean section, and maternal mortality are significantly higher in pregnant women with COVID-19 infection (10). In fact, one of the possible reasons for this can be the higher rate of disease induction in women with COVID-19 in the third trimester of pregnancy mentioned. Seif et al. (11) also showed in their study that the frequency of premature delivery was higher in patients who were infected with COVID-19 in the first trimester of pregnancy than in patients who were infected in the second and third trimesters.
Infants who were born to pregnant women with COVID-19 infection were significantly more likely to require hospitalization in the intensive care unit compared to the control group. These infants were mostly hospitalized due to pneumonia and respiratory infections, but the control group infants were mostly hospitalized due to jaundice. Also, the babies in the two groups had no significant differences in terms of hearing defects and growth. In line with the results of the present study, it was also found in the evaluations carried out by Karacam et al. that the need for hospitalization of infants in the neonatal intensive care unit was significantly higher in pregnant women with COVID-19 infection (10).
5.1. Conclusions
The results of this study showed that COVID-19 can cause some maternal complications. Therefore, pregnant women should be prepared for this infection. It is suggested to implement awareness programs to prevent maternal infection in order to improve outcomes and access to special care. Also, by adopting preventive health and treatment measures, pregnant mothers, who are a vulnerable group to this virus, can be prevented from getting infected and from heavy medical expenses for these mothers and their babies.
