At this time, very little is known about the effect of COVID-19 on pregnant women and infants. There are currently very few specific recommendations to pregnant women regarding the evaluation or management of COVID-19.
With my daughter in law moving closer to the third trimester of her second pregnancy and my son in almost daily contact with COVID-19 patients at his workplace, I decided to pore over the scarce literature available on COVID-19 and pregnancy.
Pregnant women are particularly susceptible to respiratory infections including pneumonia. This may be caused by their relative immunosuppressive state. Furthermore, physiologic adaptive changes during pregnancy (e.g., elevation of the diaphragm, increased oxygen consumption, and edema of respiratory tract mucosa) render them less tolerant to hypoxia (1).
According to Icelandic data, the 1918 influenza pandemic caused a mortality rate of 2·6% in the overall population, but 37% among pregnant women (2). Hence, pregnant women appeared to have an extremely poor prognosis.
Pregnant women were more than four times more likely to be admitted to the hospital for the 2009 swine-origin influenza A (H1N1) than the general population (3)
Furthermore, pregnant women are known to be at greater risk of severe morbidity and mortality from other respiratory infections such as influenza and severe acute respiratory syndrome caused by the SARS-associated coronavirus (SARS-CoV)(4).
SARS during pregnancy is associated with a high incidence of spontaneous miscarriage, preterm delivery, and intrauterine growth restriction. However, there is no evidence of perinatal SARS infection among infants born to these mothers (5).
Currently, available data on COVID-19 does not indicate that pregnant women are at increased risk. Nevertheless, because of the experience with SARS-CoV in 2003-2004, pregnant women should be considered an at-risk population for COVID-19.
The Symptoms of COVID-19
The most common symptoms of COVID-19 are fever, tiredness, and dry cough (7)
Some patients may have aches and pains, nasal congestion, runny nose, sore throat or diarrhea. These symptoms are usually mild and begin gradually. Some people become infected but don’t develop any symptoms and don’t feel unwell. Most people (about 80%) recover from the disease without needing special treatment.
Around 1 out of every 6 people who get COVID-19 becomes seriously ill and develop difficulty breathing. Older people, and those with underlying medical conditions, are more likely to develop serious illness.
Pneumonia and sequential multi-organ failure are the most dreaded complications of COViD-19.
COVID-19 in Pregnant Women and Infants
Despite extensive studies of patients with COVID-19 pneumonia, studies of pregnant women with COVID-19 pneumonia remain relatively rare.
Although early studies have provided some clue, it is not known whether the clinical characteristics of pregnant women with COVID-19 pneumonia differ from those of nonpregnant women with COVID-19 pneumonia. Furthermore, it is not clear whether pregnancy and childbirth aggravate COVID-19 pneumonia symptoms.
One Chinese study described the clinical manifestations and CT features of 15 pregnant women with COVID-19 pneumonia and monitored for changes before and after delivery (9).
Eleven patients had successful deliveries (10 cesarean deliveries and one vaginal delivery) and four patients were still pregnant (three in the second trimester and one in the third trimester) at the end of the study period. No cases of neonatal asphyxia, neonatal death, stillbirth, or abortion were reported.
The most common onset symptoms of COVID-19 pneumonia in pregnant women were fever (13/15 patients) and cough (9/15 patients). CT images obtained before and after delivery showed no signs of pneumonia aggravation after delivery. The four patients who were still pregnant at the end of the study period were not treated with antiviral drugs but had achieved good recovery.
The authors of the paper concluded that pregnancy and childbirth did not aggravate the course of COVID-19 pneumonia. All the cases of COVID-19 pneumonia in pregnant women in the study were the mild type. All the women in this study achieved good recovery from COVID-19 pneumonia.
Another study reported clinical data from nine pregnant women with laboratory-confirmed COVID-19 pneumonia. The clinical characteristics of these patients with COVID-19 infection during pregnancy were similar to those of non-pregnant adults with COVID-19 infection (1).
All the deliveries were performed by a cesarean section.
Pregnancy and delivery did not aggravate the severity of COVID-19 pneumonia. None of the nine patients developed severe pneumonia or died, as of Feb 4, 2020.
According to the study, pregnant women with COVID-19 pneumonia show a similar pattern of clinical characteristics to non-pregnant adult patients.
Apgar scores of all neonates were 8 or greater, and there were no cases of neonatal asphyxia or neonatal death.
The main focus of the study was to investigate the possibility of intrauterine transmission of COVID-19 infection. Tests were performed on amniotic fluid, cord blood, and neonatal throat swab samples at birth to ascertain the possibility of intrauterine fetal infection.
The results show that SARS-CoV-2 was negative in all of the above samples, suggesting that no intrauterine fetal infections occurred as a result of COVID-19 infection during the late stage of pregnancy.
The authors concluded that there is currently no evidence to suggest that the development of COVID-19 pneumonia in the third trimester of pregnancy could lead to the occurrence of severe adverse outcomes in neonates or an infection of the fetus that might be caused by intrauterine vertical transmission.
In a review of 38 pregnant women with COVID-19, no cases of intrauterine transmission and no maternal deaths were documented (11).
A recently published case report, however, has reported a newborn with elevated IgM antibodies to SARS-CoV-2 born to a mother with COVID-19 (12). At this time, the relevance of this preliminary observation is unknown.
A recent research letter published in The Lancet reported that among 33 infants born to mothers with COVID-19, three neonates (9%) with early-onset COVID-2 infection were detected. Because strict infection control and prevention procedures were implemented during the delivery, it is likely that the origin of the SARS-CoV-2 in the neonates was from their mother (13).
So far, must studies suggest that the symptoms of infants born to mothers with COVID-19 seem to be mild and the outcome appears favorable.
Currently, the primary concern is not whether the virus can be transmitted through breastmilk, but rather whether an infected mother can transmit the virus through respiratory droplets during the period of breastfeeding (6).
A mother with confirmed COVID-19 should take all possible precautions to avoid spreading the virus to her infant, including washing her hands before touching the infant and wearing a face mask, if possible, while breastfeeding.
In limited case series reported to date, no evidence of virus was found in the breast milk of women infected with COVID-19 (6). However, these data do not exclude that COVID-19 can be transmitted through breast milk.
Outside of the immediate postpartum setting, the CDC recommends that a mother with COVID-19 should continue breastfeeding or feeding expressed breast milk to her infant while taking precautions to avoid spreading of the virus to the newborn baby (13).
It is unknown if pregnant women have a greater risk of getting sick from COVID-19 than the general public or whether they are more likely to have a serious illness.
However, at this time there is no evidence that pregnancy and childbirth aggravates the course of pneumonia in women with COVID-19. Nevertheless, because of the experience with SARS-CoV in 2003-2004, pregnant women should be considered an at-risk population for COVID-19.
Despite contradictive evidence, recent data suggest that pregnant women with COVID-19 can in some cases pass the virus to her unborn child.
However, the symptoms of infants born to mothers with COVID seem to be mild and outcome appears favorable.
Pregnant women should take the following actions to prevent the spread of COVID19:
- Cover your cough (using your elbow is a good technique)
- Avoid people who are sick
- Clean your hands often using soap and water or alcohol-based sanitizer
Our knowledge of COVID-19 changes rapidly day by day. I will do my best to provide updated information here as new data comes along.