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Data regarding the effects of coronavirus disease 2019 (COVID-19) during pregnancy are scarce. To date there have been three research letters published in the medical literature about a possible connection between maternal infection with SARS-CoV-2 (the virus that causes COVID-19) and miscarriage. I will summarize each of them here.
Before that, though, I will remind the reader that scientists’ knowledge about the effects of the novel coronavirus (SARS-CoV-2) on pregnant women is grounded in what we know about other coronavirus infections studied in the past, namely SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome), and their effects on pregnant women. Studies have shown that both SARS and MERS cause placental insufficiency—meaning the placenta does not function as well as it should to deliver nutrients to the fetus from the mother—which has resulted in both miscarriage and intrauterine growth restriction. That is to say, SARS and MERS in pregnant women have been known to be associated with miscarriage and low-birth-weight babies. It is important to note that possible placental insufficiency has also been seen in SARS-CoV-2.
“Change in the Incidence of Still-birth and Preterm Delivery During the COVID-19 Pandemic”
The first research letter I would like to summarize here is called “Change in the Incidence of Still-birth and Preterm Delivery During the COVID-19 Pandemic.” It was published in the Journal of the American Medical Association in July of 2020. This small study compared a 4-month pre-COVID period of time in late 2019/early 2020 with a 4-and-a-half-month time period in 2020 during the pandemic. Researchers found that there was an uptick in the numbers of stillbirths since the beginning of the pandemic.
The question remains, however, is this uptick in numbers directly associated with SARS-CoV-2 infection? The researchers were unable to answer this question. None of the women in the study had confirmed COVID-19. A huge caveat here is that at the time the study was taking place, policy was that only symptomatic patients were to be tested for the virus. As we now know, many cases of COVID-19 are asymptomatic, meaning the patients appear healthy even though they are harboring the virus. This means the researchers cannot be certain whether or not any of the women in the study were infected.
Another reason the researchers gave for not being able to answer the question of whether or not the miscarriages were COVID-related was that perhaps women were reluctant to seek prenatal care for fear they would contract the virus. This lack of care and screening could lead to an increased rate of miscarriage.
“Second-Trimester Miscarriage in a Pregnant Woman with SARS-CoV-2 Infection”
The next letter I would like to address is called “Second-Trimester Miscarriage in a Pregnant Woman with SARS-CoV-2 Infection.” It was published in April 2020 in the Journal of the American Medical Association. This letter presents information about a pregnant woman who miscarried at 19 weeks. She originally sought medical care for a fever, muscle aches, fatigue, sore throat, cough, and diarrhea that she had been experiencing for 2 days. She tested positive for SARS-CoV-2 and released home to quarantine.
Two days later, the woman started experiencing uterine contractions in addition to her other symptoms. She presented to the hospital and, after laboring for 10 hours, she gave birth to a stillborn baby. The baby tested negative for the novel coronavirus. Interestingly, samples from the fetal surface of the placenta tested positive for SARS-CoV-2. There were also findings that were suggestive of an inflammatory response in the fetus.
The researchers concluded that the miscarriage in this case appeared to be “related to placental infection.”
“Late Miscarriage as a Presenting Manifestation of COVID-19”
The last letter is called “Late Miscarriage as a Presenting Manifestation of COVID-19.” It appeared in the European Journal of Obstetrics & Gynecology and Reproductive Biology in July of 2020. This letter details a miscarriage that took place at 20 weeks to a woman who presented to the hospital with vaginal bleeding and uterine contractions.
The patient had no symptoms of infection with the novel coronavirus. However, she worked in a healthcare facility that cared for patients who had tested positive for COVID-19. She was tested for SARS-CoV-2. The test came back positive. Results were negative for the fetus. After miscarrying, the patient quickly developed trouble breathing. Imaging showed extensive pneumonia.
The researchers think miscarriage could be a possible way that pregnant women who are fighting COVID-19 present to the hospital.
If you are pregnant, you want to take extra care in protecting yourself against contracting COVID-19. Precautions include staying home when you can, limiting your social contacts, wearing a mask when out of your home, encouraging others outside your immediate family to wear a mask around you, social distancing, and washing hands often. Additionally, you want to keep up on all of your prenatal check-ups and screenings. Don’t hesitate to contact your doctor if you have any concerns regarding your pregnancy.