by Michael Stanclift, ND
Expectant mothers may find some reassurance in recent evidence suggesting COVID-19 infection during pregnancy doesn’t appear to pose the same dangers as related viral infections (e.g. SARS, MERS).1 Pregnant women contracting COVID-19 must still be cautious about their and their developing babies’ health, especially since treatment options are more limited during pregnancy; however, documented cases give us some insight into the short-term effects. As with all things related to COVID-19, the data is still emerging, and we must keep in mind that new information could further support or undermine what we know now. Data on pregnancy is limited by the number of cases and the time frame of the pandemic—meaning we will not know longer range effects or the validity of these findings for some time.
COVID-19-positive pregnant women mostly without symptoms
Doctors in a London hospital during its COVID-19 peak detected coronavirus (SARS-CoV-2) in 7% of pregnant women admitted for delivery; nearly all of them (89%) had no symptoms.2 During the pandemic peak in New York, the positive rate for SARS-CoV-2 in pregnant women was over twice as high as London (15%), with a similar number of them asymptomatic as well.2,3 The authors expressed concern that their findings support a trend of asymptomatic infection in healthcare facilities, suggesting poor infection control.2
What happens when a pregnant woman gets COVID-19
Unlike with infections such as influenza, pregnant women do not appear to be at increased susceptibility for COVID-19 infection, nor do they have more severe disease when they contract it.4 COVID-19 infection in pregnant women presents in much the same way as in nonpregnant patients—usually with a cough, fever, labored breathing, and low lymphocytes.1 Compared to infections caused by similar coronaviruses (SARS/MERS), the death rate in pregnant women with COVID-19 has yet to be determined; initial reports are very low, while SARS/MERS respectively have an 18% and 25% mortality rate in this population.1,5,6
- 1st trimester: In other infections, developing a fever in the first trimester doesn’t contribute to birth defects, though it does increase the likelihood of inattention disorders in childhood.1 Because of the timeline of the pandemic, we don’t have data on COVID-19-related effects from young children born to mothers who had the infection, but experts hypothesize the same may hold true.1 Based on small numbers of COVID-19 cases, it doesn’t appear to increase the risk for miscarriage (spontaneous abortion) above the risk of the general population.1,7
- 2nd/3rd trimester: Data from small numbers of cases show COVID-19 infection poses fetal risks, such as intrauterine growth restriction (9-10%) and preterm birth (39-43%), though the preterm birth information is somewhat conflicting.1,7,8
- Early childhood: COVID-19 presents mostly as a mild respiratory illness in most children.1
- Predicting severity of COVID-19 in pregnancy: Assessing and predicting mortality of COVID-19 in pregnant patients is more difficult than in nonpregnant patients, as the normal course of pregnancy skews measures used to predict the course of disease, such as D-dimer and sequential organ failure assessment (SOFA).1 This can make it a bit more difficult to predict when the severity of a case may increase and require higher levels of interventions.
- Treatment of COVID-19 in pregnancy: Pregnant women who develop severe disease and require a ventilator need higher levels of oxygen to adequately provide for their growing fetus.1 Remdesivir, the most promising drug for the treatment of COVID-19, appears to be safe for use during pregnancy, as does chloroquine, though it may require higher doses in pregnant patients.1 An HIV antiviral being used, lopinavir-ritonavir, is safe in pregnancy, as demonstrated through public health data.1 Unfortunately, ribivarin, an antiviral drug, and baricitinib, a Janus kinase inhibitor being used for COVID-19, aren’t safe to use during pregnancy.1 Pregnant and breastfeeding women are excluded from current vaccine phase 1 and 2 clinical trials, though some OB/GYNs argue this is “both misguided and not justifiable and may have excluded them from potentially beneficial interventions.”9-11
- Special considerations for pregnant healthcare workers: N95 masks can reduce oxygen uptake and are recommended against (as is frontline work) for pregnant women working in healthcare with growth-restricted fetuses.1
- Vertical transmission (mother spreading the virus to baby): In theory, passing the infection from mother to baby while in utero is possible due to ACE2 (the receptor the virus uses to enter cells) expression on the placenta; however, no confirmed cases proving this have been recorded to date.1 A study published in JAMA found IgG and IgM antibodies against SARS-CoV-2 in newborn infants born to COVID-19-positive mothers.12 Since IgM does not cross the placenta, it suggests the infants were possibly exposed to the virus in utero; however, throat swabs and blood samples from the babies were negative for the virus.12 Measuring IgM antibodies has limitations with the possibility of false positives, so more evidence is needed to confirm the infection could be passed this way.13 In cases where a baby tested positive after being delivered by a COVID-19-infected mother, other causes of transmission could not be completely ruled out.1 Additionally, in COVID-19-positive mothers the virus does not seem to appear in amniotic fluid, umbilical cord blood, breast milk, or throat swabs from the infants.1
- Delivery, breastfeeding, and skin-to-skin contact: Numerous reputable professional obstetrics societies declare vaginal delivery is safe for women with COVID-19, without risk of spreading the infection to the infant.1,8 Women with the infection may need to wear a facemask and avoid skin-to-skin contact with their new babies after delivery; however, all evidence suggests it is safe for the baby to drink breastmilk—which should bring some comfort to both.1
Pregnant women are not more likely to get COVID-19, nor are they more likely to have a severe case based on the findings so far. While COVID-19 infection during pregnancy certainly presents possible risks to them and their babies, the emerging evidence is reassuring. In the absence of other modifying factors that increase risk and course of disease, pregnant women can reasonably expect that contracting COVID-19 while pregnant has the same risks as nonpregnant patients of similar makeup. Treatment options for pregnant women are mostly similar, with some limitations. There is no compelling evidence that pregnant women can spread the infection to their babies, other than normal transmission routes, namely respiratory droplets. Should their babies develop the infection, the course is generally mild in children.
The American College of Obstetricians and Gynecologists (ACOG) along with the Centers for Disease Control (CDC) has created guidelines based on the available research to date; however, there are still several unanswered questions, and additional information is needed to make better informed decisions. Therefore, those clinicians with pregnant women under their care should routinely monitor any changes and updates to these recommendations.
- Dashraath P et al. Coronavirus disease 2019 (COVID-19) pandemic and pregnancy. Am J Obstet Gynecol. 2020. pii: S0002-9378(20)30343-4.
- Khalil A et al. SARS-CoV-2 in pregnancy: symptomatic pregnant women are only the tip of the iceberg. Am J Obstet Gynecol. pii: S0002-9378(20)30529-9.
- Coronavirus Resource Center. Johns Hopkins University and Medicine. https://coronavirus.jhu.edu/map.html. Accessed May 14, 2020.
- Blitz MJ et al. Intensive care unit admissions for pregnant and non-pregnant women with COVID-19. Am J Obstet Gynecol. 2020. pii: S0002-9378(20)30528-7.5.
- Karami P et al. Mortality of a pregnant patient diagnosed with COVID-19: A case report with clinical, radiological, and histopathological findings. Travel Med Infect Dis. 2020;101665.
- Hantoushzadeh S et al. Maternal death due to COVID-19 disease. Am J Obstet Gynecol. 2020;S0002-9378(20)30516-0.
- Yan J et al. Coronavirus disease 2019 (COVID-19) in pregnant women: A report based on 116 cases. Am J Obstet Gynecol. 2020;S0002-9378(20)30462-2.
- Della Gatta AN et al. COVID19 during pregnancy: a systematic review of reported cases. Am J Obstet Gynecol. 2020;S0002-9378(20)30438-5.
- Safety and immunogenicity study of 2019-nCoV vaccine (Mrna-1273) for prophylaxis of SARS-CoV-2 iInfection (COVID-19). ClinicalTrials.gov. https://clinicaltrials.gov/ct2/show/NCT04283461?term=mrna-1273&draw=2&rank=1. Accessed May 13, 2020.
- Safety, tolerability and immunogenicity of INO-4800 for COVID-19 in healthy volunteers. ClinicalTrials.gov. https://clinicaltrials.gov/ct2/show/NCT04336410?term=ino-4800&draw=2&rank=1. Accessed May 13, 2020.
- Costantine MM et al. Protection by exclusion: Another missed opportunity to include pregnant women in research during the coronavirus disease 2019 (COVID-19) pandemic. Obstet Gynecol. 2020. [Epub ahead of print].
- Zeng H et al. Antibodies in infants born to mothers with COVID-19 pneumonia. JAMA. 2020;323(18):1848‐1849.
- Kimberlin DW et al. Can SARS-CoV-2 infection be acquired in utero?: Moredefinitive evidence is needed. JAMA. 2020. [Epub ahead of print].
Michael Stanclift, ND is a naturopathic doctor and senior medical writer at Metagenics. He graduated from Bastyr University’s school of naturopathic medicine and practiced in Edinburgh, Scotland, and Southern California. He enjoys educating other healthcare providers and impacting the lives of their many patients. When he’s not working, he spends his hours with his wife and two children.