Covid-19 and pregnancy: the experience of a tertiary maternity hospital

Introduction

In December 2019, a pneumonia caused by novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) emerged in Wuhan, the capital of Hubei province, in China [1]. Since then, the infection has spread to different areas of China and other parts of the world [1]. World Health Organization (WHO) announced SARS-CoV-2 as cause of pneumonia on January 9, 2020, and declared a pandemic on March 11, 2020 [2]. The SARS-CoV-2 causes the coronavirus disease 2019 (COVID-19) with symptoms ranging from mild disease to pneumonitis, acute respiratory distress syndrome (ARDS) and death. Globally, as of 6 February 2021, 104,790,123 cases of COVID-19 have been reported, including 2,285,048 deaths [3]. The first reported case in Greece was reported on the 27th of February 2020. Since then, there have been 160,935 confirmed cases and 5,903 deaths from COVID-19 [3].

Inevitably the number of COVID-19 positive pregnant women is rising on par with the general population. At the same time, information about the effects of COVID-19 during pregnancy is evolving rapidly. Initial reports suggested that the severity of the illness in pregnant patients is similar with the general population [4], [5]. However, later reports suggested higher rates of intensive care unit admissions, invasive ventilation and mortality among pregnant patients compared to the general population [6]. Pneumonia remains one of the leading causes of pregnant women mortality worldwide [7]. Pregnant women are considered high risk for viral infections, such as SARS-CoV-2, due to the effects of pregnancy on the immunity response [8]. Furthermore, there are concerns regarding the association of SARS-CoV-2 and fetal growth restriction (FGR) after maternal infection, due to placental lesions related to acute illness, increased coagulopathy, hypoxia and placental viral infection which have been observed in numerous occasions [9], [10], [11], [12], [13]. Hence, management of COVID-19 positive pregnant women remains challenging.

The objective of our study is to present the maternal and neonatal outcomes of COVID-19 positive pregnant women, who were admitted to our tertiary maternity hospital since the beginning of the pandemic in Greece.

Materials and methods

All COVID-19 positive pregnant women who were admitted to our clinic from March to December 2020 were included in the study. We documented the demographic data, clinical characteristics, laboratory values, maternal and fetal outcomes. More specifically we documented maternal age, body mass index (BMI), blood group, gravidity, parity, indication for admission, comorbidities, gestational age (GA), pregnancy complications, initial COVID-19 symptoms, hematological and biochemical results, indication and mode of delivery, hospitalization length and final outcome. Similarly, we documented neonatal birthweight, sex, Apgar score, neonatal COVID-19 status, neonatal morbidity, neonatal intensive care (NICU) admission and final outcome.

Assessment of SARS‐CoV-2 in nasopharyngeal samples was performed by real-time polymerase chain reaction (RT‐PCR) targeting the ribonucleic acid (RNA)‐dependent RNA polymerase (RdRp) gene. Sterile Dacron or Rayon swabs with flexible plastic shafts were used to collect nasopharyngeal samples from patients. After collection, swabs were placed into 2 mL of sterile viral transport medium (VTM; various manufacturers) and all specimens were analyzed by the university laboratory.

Informed consent was obtained from all pregnant women included in this study. Cumulative data of continuous variables was reported in mean ± SD.

Ethical approval: Research relating to human subjects complied with national regulations, institutional policies the tenets of the Helsinki Declaration [14], and has been approved by the authors’ hospital Institutional Review Board.

Results

A total of 40 pregnant women tested positive for COVID-19 from March till December 2020 and were included in our study. Mean age at the time of diagnosis was 28 years (SD 6.3 years) and mean BMI was 26.2 kg/m². Mean GAe at diagnosis was 37⁺³ weeks and 38 of them were at the third trimester. The majority of women (n=35/40) were asymptomatic at the time of diagnosis and remained asymptomatic throughout the study period. About 27% of the study population (n=12/40) had comorbidities, such as morbid obesity (BMI 51.3 kg/m²), gestational diabetes mellitus (GDM), asthma, epilepsy, hepatitis B, hypothyroidism and thrombophilia. Initial symptoms included cough, sore throat, fever and dyspnea. A small percentage of symptomatic pregnant women (5%) needed oxygen, while none of the women were admitted to the Intensive Care Unit (ICU). Chest radiograph was performed in two cases and one had radiographic findings suspicious for COVID-19 pneumonia. The most common blood group among positive pregnant women was A+ and the mean leukocyte count was 10.1 × 10⁶/mm³ (SD 3.3). Demographic features and clinical characteristics are shown in Table 1.

Discussion

Our study has demonstrated that COVID-19 during pregnancy in the majority of cases has mild clinical course. A high rate of asymptomatic COVID-19 positive pregnant women was documented (n=35/40), as expected by the relatively high documented number of asymptomatic pregnancies [15]. As COVID-19 positive asymptomatic individuals pose a great risk for spreading the virus to other patients and healthcare providers, universal testing of hospitalized pregnant women on the day of admission has been adopted as a standard protocol.

Women in labor or needing immediate medical attention were divided in two categories while the COVID-19 test results were pending. Asymptomatic women, without any contact with COVID-19 patients in the near past were characterized as low-risk and treated as usual. Women who presented with symptoms such as fever, cough, dyspnea, had close contact with confirmed COVID-19 positive patients or resided in closed communities (such as prisons, institutions and immigration camps) with recent COVID-19 cases, were characterized as high risk for COVID-19 infection and they were examined or delivered in a separate hospital ward.

High risk pregnant women whose RT-PCR COVID-19 test result was pending were kept in isolation.

Hospital infrastructure was modified in order to adopt the necessary changes to accommodate, treat and deliver COVID-19 positive pregnant women. Aeration of the operating room was stopped to limit the spread within the hospital. One ward was allocated for the hospitalization of COVID-19 positive women and another ward for the high risk pregnant women whose RT-PCR test was pending. A separate ward was used for delivering or operating on the high risk or positive pregnant patients.

Hospital policy dictated that the patient wore a surgical mask throughout the duration of hospital stay. Hand hygiene, use of N-95/FFP2/FFP3 masks, face shields, feet protection, two sets of gloves and Tyvek or waterproof uniforms were used for protection of the hospital staff when taking care of COVID-19 positive or high risk women.

Breastfeeding was encouraged in all cases, while COVID-19 positive mothers were instructed regarding proper hygiene.

None of the 35 neonates who were delivered from COVID-19 positive women tested positive for SARS-CoV-2. However, perinatal complications were reported in some cases. We documented high rates of FGR (n=3/40) but the presence of concurrent maternal pathology (gestational hypertension, GDM etc.) does not allow for speculation regarding the etiology of FGR.

Breastfeeding was encouraged in our department as there are no evidence regarding transmission of SARS-CoV-2 through the breast milk [16], [17]. As a result 22 out of 35 women elected to breastfeed with none of the infants testing positive of COVID-19 until discharge from the hospital, approximately three to 4 days post-delivery.

As this global epidemic continues to develop, additional information regarding the effects of COVID-19 on pregnant women and their infants will become available. Recommendation on the subject of obstetric management during the pandemic are available from most Obstetric Colleges and Associations and they are being updated regularly as new information becomes available [18–20].

Vaccination against COVID-19 has begun in the United States of America since the 11th of December 2020, when the Food and Drug Administration issued an Emergency Use Authorization for the (BNT162b2) messenger ribonucleic acid (mRNA) vaccine in individuals 16 years of age and older [21]. Despite the promising results of vaccination (which has been shown to be 95% effective at preventing COVID-19), pregnant women were not included in the vaccine’s clinical trials [21]. However, on the 13th of December 2020 the American College of Obstetricians and Gynecologists issued a practice advisory supporting vaccination of pregnant women against COVID-19 after informing the pregnant women of the safety of mRNA vaccines in pregnancy and the risks of maternal disease to the mother and the fetus [22]. According to Society of Obstetricians and Gynecologists of Canada, pregnant and breastfeeding women were excluded from the Phase II and Phase III studies for the COVID-19 vaccine. However, there were 23 women (12 in the vaccine arm and 11 in the placebo arm) who reported pregnancies during the trial and are being followed for pregnancy outcomes with no reports of adverse effects [23].

Conclusions

In accordance with other studies, COVID-19 infection causes mild-to-moderate symptoms while many infected individuals are asymptomatic. As our knowledge regarding COVID-19 infection of pregnant women is being updated on a daily basis, there is need for flexibility regarding the allocation of resources, equipment and healthcare workforce. Data regarding first and second trimester infection is insufficient for optimal management. More data and follow up are still needed.