What does protecting the lives of unborn children look like in the era of Covid-19?
Covid-19 prevention measures have, sadly, become highly politicized. In this article I will address the risks Covid-19 poses to pregnant women and their children and discuss the available safety and efficacy data for Covid-19 vaccines. I will not address vaccine mandates or vaccine passports, which are policy issues separate from the issue of whether the pro-life community should support Covid-19 vaccine use by individuals.
I write from my expertise as a scientist and my experience as a mother, and I focus on what we know from the data. I hold a doctorate in biomedical engineering from Rice University and currently work as a Research Scientist for the Rice360 Institute for Global Health Technologies, where I develop medical tools to improve care for newborns and mothers in low-resource settings. I am also a mother of four: one wonderful living son and three precious babies lost to miscarriage. I have suffered the pain of infertility and loss and understand the great concerns many pregnant women have about new interventions during pregnancy.
The scientific community has learned so much in the last two years of fighting this new virus. Initial recommendations in early 2020 did not list pregnancy as a risk factor for severe disease, but on-the-ground research has demonstrated that pregnant women and their babies are at a higher risk for complications from Covid than their non-pregnant counterparts. Exactly which complications and how much more at risk they are remain under investigation. One challenge is the timeline of pregnancies, pandemic, and scientific publishing: For example, at the time I’m writing this article, the Delta variant has not been dominant for an entire full-term pregnancy (though preliminary research is showing Delta-variant Covid is harming pregnant women and babies more than previous variants did). The new Omicron variant just began emerging as a significant and growing percentage of American Covid cases as I was completing this article, and there have been no publications on whether and how it may vary in its effects on pregnant women and their babies. Another challenge is that different peer-reviewed studies are comparing different groups: all pregnant women during Covid, pregnant women with a positive Covid test, or pregnant women with symptomatic Covid, versus asymptomatic pregnant women, non-infected pregnant women, or non-pregnant people with or without Covid; this makes combining studies to draw large conclusions difficult. However, some clear trends are emerging.
Effects of Covid-19 on Mothers and Babies
In general, we are fortunate that the course of the disease among pregnant women seems similar to that of their non-pregnant counterparts, and the small number of newborns who are infected during birth typically do well.1 Absolute numbers of deaths and adverse events are low, but the converging data indicate that pregnant women and their babies do suffer excess morbidity and mortality from Covid-19 due to pregnancy. As of January 3, 2022, the CDC reports that at least 155,587 pregnant women have contracted Covid in the U.S.; 257 of these women have died.2 In the Americas as a whole, more than 270,000 pregnant women have contracted Covid and 2,600 have died, making Covid the leading cause of maternal mortality in 2021 in Mexico and Columbia (Covid was linked to more than 25 percent of maternal deaths in Mexico in 20203).4
While we know that every fetus of a mother infected with Covid-19 is subject to the elevated risks of miscarriage, stillbirth, pre-term birth, and NICU admission, hard numbers on how many babies have suffered those effects is harder to determine due to a lack of global data on fetal death. The UN Interagency Group for Child Mortality Estimation has predicted that Covid infection and Covid-related health system disruptions could cause an additional 60,000 to 200,000 stillbirths per year worldwide.5
The data show that Covid-19 infection increases risk of stillbirth, and the risk has been increasing with the growing prevalence of the Delta variant: In the U.S., 2.7 percent of deliveries with Covid-19 resulted in stillbirth when Delta was dominant, compared with 0.6 percent of deliveries without Covid in the same period.6 Globally, Chmielewska et al.’s review compared outcomes pre-pandemic to those during the pandemic (pre-Delta), and separated high from low and middle income countries (HIC vs. LMIC). The pandemic has resulted in a significantly increased rate of stillbirth (odds ratio 1.28) and maternal death (odds ratio 1.37) in LMICs, and a significantly increased rate of preterm birth (before 37 weeks gestation) in high-income countries.7 Note that this study merely compares rates of stillbirth and preterm birth before and during the pandemic. It does not distinguish between infected and noninfected mothers, and it thus includes both the effects of Covid-19 infection and Covid-19’s detrimental effects on the healthcare system, which have been especially devastating in resource-limited settings that were already struggling to provide adequate maternal and newborn care.
Covid’s effect on miscarriage rate is less clear: Some studies show that Covid infection does not increase risk of miscarriage8,9 and some studies show a slight increase10; however, sample sizes are very limited, and there are few good studies. Cavalcante et al. noted that there may be some evidence for increased miscarriage risk in those with symptomatic Covid infection (as compared to any Covid infection), but sufficient data were not available to conclude this with confidence. There are reasons to believe that Covid-19 infection near conception may cause pregnancy loss,11 and multiple case reports have reported problems in the placenta following even mild Covid infection,10,12–15 which can lead to intrauterine growth restriction, miscarriage, or stillbirth.
Sadly, the stress of the pandemic has resulted in further loss of life; there were 4,500 more elective abortions in the U.K. in April 2020, following that nation’s lockdown on March 18, than in April 2019, the year before Covid.1 We must also consider morbidity: How many pregnant women and their babies are suffering devastating side effects from Covid-19? Pregnant mothers tend to have fewer symptoms of Covid than non-pregnant women, but when they do have symptoms, they can be more severe.1,16 Pregnant women have higher rates of hospitalization (31.5 percent of pregnant women compared to 5.8 percent of non-pregnant women1), ICU admission, need for mechanical ventilation, need for extracorporeal membrane oxygenation (ECMO, that is, oxygenating the blood with a heart-lung machine to sustain life), and death.16–19 The rates of these complications vary depending on the specific population, time in the pandemic, control group, and decisions of the treating physicians. For example, Sankaran et al. found that 1 percent of symptomatic pregnant women required ICU admission compared to 0.4 percent of symptomatic non-pregnant women, while Mark et al. found 11 percent of pregnant women with Covid were admitted to the ICU. In addition, other adverse outcomes have been reported, such as increased rate of C-section due to maternal breathlessness, pre-eclampsia, postpartum hemorrhage, and deep vein thrombosis.10
Babies born to mothers who have had Covid-19, especially later in pregnancy, experience higher rates of preterm birth, NICU admission, and stillbirth.10,16 Allotey et al. report that 33 percent of newborns born to Covidpositive mothers were admitted to the NICU.
Most of these studies were conducted before the Delta variant was dominant, and due to the scientific publishing timeline, we have little information on how Delta has changed the severity of Covid-19 for pregnant women and their babies. Delta has significantly increased transmission and has placed extraordinary burdens on the healthcare system in many parts of the world; this strain can transform conditions that are ordinarily easily treated, such as gallstones, into deadly conditions due to a lack of space and skilled care—even in the high-resource setting of Houston, Texas, home of the largest medical center in the world.20 The CDC recently released a report showing an almost five-fold increase in the rate of maternal mortality in Mississippi due to Delta: Before Delta, pregnant mothers died at a rate of 5 per 1000 Covid infections; during Delta, the rate jumped to 25 per 1,000 Covid infections during pregnancy.21 In Alabama, a small study showed that Delta is significantly increasing the percentage of Covid-positive pregnant women who are symptomatic (84 percent during Delta, 54 percent before Delta), who have severe to critical disease (36 percent during Delta, 13 percent before Delta), who require ICU admission (29 percent during Delta, 8 percent before Delta), and who require a C-section due to worsening maternal status (71 percent during Delta, 14 percent before Delta); the percentage of Covidpositive pregnant women with babies born before 37 weeks also increased substantially with the ascendancy of Delta (73 percent during Delta, 32 percent before Delta).22 A study in Galveston reports similar increases.23 In Dallas, Delta resulted in over 25 percent of Covid-positive pregnant women needing hospital admission for severe or critical illness.24
A broad sampling of hospitals in the U.S. found that during the pre-Delta period, 1 percent of pregnant mothers with Covid lost their babies to stillbirth; during Delta, that percentage increased to 2.7 percent.6
I expect larger and more detailed studies on Delta and pregnant women and their babies to be published in the coming months.
Severe Covid-19 is survivable when the health system is able to provide care and support, such as oxygen, mechanical ventilation, C-section, and skilled nursing care. However, those resources are reduced when caseloads soar, which occurred in many parts of the U.S. in the fall of 2021, and which occurs continually in low-resource settings that suffer high maternal and newborn mortality even without Covid-19.
So what can we do? Three Covid vaccines are currently available to the general public in the United States—but are they safe for pregnant women and their babies, and safer than the infection itself? Happily, we now have significant evidence that yes, these vaccines are safe and effective even in pregnant women, and are significantly safer than infection with Covid-19.
Initial evidence on vaccine safety in pregnancy was limited because of the traditional exclusion of pregnant women from the first round of trials. This exclusion protects women, their babies, and manufacturers from tragedies that may occur during the testing of newly developed medications; however, exclusion from trials also delays the benefits of research from reaching pregnant women—an especially large problem during a crisis like a global pandemic.
From the initial FDA applications of Pfizer, Moderna, and Johnson & Johnson, we learned that the DART studies (Developmental And Reproductive Toxicity) performed on rats showed no vaccine problems for the mothers or babies, and the handful of women who became pregnant during the human trials had rates of adverse pregnancy outcomes similar to or smaller than the placebo groups.25–29 In the period since these vaccines were approved under Emergency Use Authorization (EUA) in late 2020 and early 2021, more targeted studies on pregnant women have been done.
The most convincing data would result from a randomized, placebo-controlled clinical trial, in which some pregnant women receive the vaccine and some receive a placebo. Such a trial is underway for the Pfizer vaccine,27 but results are delayed due to slow enrollment30—few women who wanted the vaccine were willing to risk receiving a placebo shot, and some doctors felt it was unethical to give the placebo after observational safety data indicated good results in pregnancy. To my knowledge neither Moderna nor Johnson & Johnson have a placebo randomized trial going on for pregnant patients. Though a placebo randomized trial is ideal, it is not the only way to achieve confidence in vaccine safety.
Tracking and reporting of adverse effects after pregnant women receive vaccines is ongoing. V-safe31 is a smartphone-based CDC system collecting reports of side effects after people receive any of the vaccines. Women who report pregnancy at the time of or after receiving the vaccine are invited to participate in the V-safe Pregnancy Registry.32 Scientists are actively monitoring these reports for any warning signs, and those results are being shared with the public. However, because V-safe contains self-reported data, without a control or placebo group, it can be difficult to tell whether a health event is due to the vaccine or would have happened anyway. Nevertheless, V-safe is one good way to monitor trends in side effects. When the data are analyzed, they are typically compared to pre-pandemic data as a substitute for a placebo control group.
The first publication on this data compared rates of adverse events from before the pandemic (unvaccinated women) to rates in vaccinated (Moderna or Pfizer) pregnant women.33 The rates are very similar: 10-26 percent miscarriage rate in women before the pandemic; 12.6 percent in vaccinated pregnant women. Rates for stillbirth, preterm birth, small size for gestational age, congenital anomalies, and neonatal death are all similar in non-vaccinated and in vaccinated women, results that also agree with an Israeli study.34 Further analysis published in September 2021 examined records of 105,226 pregnancies and again showed no increase in miscarriage rate due to receiving the Moderna or Pfizer vaccines (there was insufficient data to make conclusions about the Johnson & Johnson vaccine).35 Another study in Norway of over 18,000 women showed a slightly lower miscarriage rate for vaccinated women compared to unvaccinated.36 While any miscarriage is a cause for grief, these data show that receiving the Covid-19 vaccine does not increase the rate of miscarriage or other adverse pregnancy outcomes.
I will very briefly touch on the data we have for couples trying to conceive. I sympathize with people who are concerned about fertility, and I understand that because the current medical establishment is often focused on preventing fertility, it’s hard to trust them when they assert that a new intervention is safe for fertility. However, in this case, the data supports great safety for fertility. Based on how the vaccines work, scientists do not expect any adverse effects on fertility. The new mRNA vaccines (Moderna and Pfizer) work by giving the body instructions to produce only the spike protein of the Covid virus. The body reacts to this foreign protein by producing antibodies, and the mRNA instructions quickly degrade. There is no mechanism for altering one’s genomic DNA.
Many people are concerned that the vaccines may have long-term effects on fertility, but there is no evidence to support this concern. With previous (non-Covid) vaccines, all “long-term” effects have appeared within 2 months of vaccine administration (vaccines are taken once or twice and then never seen again, unlike drugs that are taken daily for long periods of time; therefore, we are more concerned with the long-term effects of those drugs taken over months or years). Two months of initial safety data were required for the vaccines to receive Emergency Use Authorization (EUA); since then, scientists have been monitoring the side effects of the vaccines for over a year with no concerning long-term side effects noted.*40,41 There is no evidence, from this vaccine or previous vaccines, to support the concern that fertility could be affected years down the road.
Concerns have been circulating that the vaccine nanoparticles pool in the ovaries and cause damage; however, these concerns originate from a poor understanding or a deliberate misreading of Pfizer data submitted to a Japanese regulatory agency.37–39 In the study, researchers injected rats with lipid nanoparticles similar to those used in the Pfizer vaccine; instead of mRNA, the nanoparticles carried a fluorescent particle so researchers could watch where the particles accumulated in the body over 48 hours. By far the greatest concentration (24.6 percent and 16.2 percent of the initial dose) accumulated in the injection site and in the liver, exactly where we would expect. In female rats, the maximum amount of particles in the ovaries was at 48 hours after injection and peaked at 0.095 percent of the initial dose. That is a tiny, tiny amount. Additionally, rats were injected with a dose approximately 1835x higher than that given to humans. This data in no way supports the claim that vaccine nanoparticles target or harm the ovary.
We have other data supporting ovarian health post-vaccination: One Israeli study examined the effect of Covid-19 infection and the Pfizer Covid vaccine on ovarian follicles.42 Several small groups of women recovering from Covid-19 infection, vaccinated women, and women who were uninfected and unvaccinated were studied when they had their eggs collected for in vitro fertilization. The scientists found anti-Covid antibodies in the follicle fluid in both recovering and vaccinated women, but there were no differences among the three groups in terms of follicle quality (estradiol, progesterone, or number of eggs). Other studies have reported no problems with embryo implantation in women43,44 or in sperm parameters45 following mRNA vaccination.
Many women are concerned about the growing reports vaccination produces menstrual changes such as early or late periods, heavier bleeding, or heavier cramping in some women. However, these changes tend to be shortlived, are likely explained by the vaccine’s stressful side effects and the endometrium’s connection to the immune system, and show no detrimental effects on fertility.46 Studies on this issue are much needed and ongoing!47 The first systematic study on this question was published in early 2022.48 This beautiful study recruited women who had been tracking their cycle lengths via the “Natural Cycles” app for at least three cycles before vaccination (2,403 women), and compared their cycle changes post-vaccination to charting women who did not receive the vaccine (1,556 women). This prospective design produces data of much higher quality than asking women after the vaccine if they noticed any changes (retrospective design). The researchers found an average increase in cycle length in vaccinated women of less than one day (for both doses of vaccine). No change in length of menses (bleeding) was seen in the vaccinated group. Some vaccinated women (approximately 10 percent) “experienced a clinically notable change in cycle length of 8 days or more, [but] this change attenuated quickly within two postvaccine cycles.” Only women with normal cycle lengths (24–38 days) were included in this study; I look forward to further reports on this topic.
As many doctors hypothesized, this change in cycle length was short-lived (returned to normal within two cycles). If these cycle changes affected fertility, we would see evidence in vaccinated women’s conception, miscarriage, or stillbirth rates—changes we are not seeing.
No concerning safety data for reproductive-age women, pregnant or not, have been reported. Due to these good reports, multiple groups now recommend that pregnant women receive the vaccine, including the CDC,49 the American College of Obstetricians and Gynecologists or ACOG,50 and the Society for Maternal-Fetal Medicine.51 These sources do recommend that pregnant women who experience fever as a vaccine side effect control it with acetaminophen to prevent adverse pregnancy outcomes; fortunately, pregnant women seem to have fewer vaccine side effects than non-pregnant people. (Since the initial writing of this article, all three groups now also recommend pregnant women and women planning to become pregnant receive a Covid-19 booster shot at the appropriate time following their initial vaccine series. There are no additional safety concerns for the booster shot.) As of this writing, only a handful of people are currently medically ineligible for vaccines: children under 5 years, people who have allergies to vaccine ingredients (this population is small because the vaccines were intentionally developed without common allergens like eggs), and people who have recently received an antibody infusion to treat Covid.52 People with concerns about specific rare side effects, like blood clotting or myocarditis, should speak to their doctor; these concerns can often be mitigated by choosing between the two different types of available vaccines.
Do Vaccines Work for Pregnant Women?
Initially there were some concerns about whether the new mRNA vaccine platform would induce immunity in the pregnant population, but the data look good. A study followed pregnant and lactating women who had been given Pfizer or Moderna vaccines.53 The authors found that:
• Vaccines induced similar antibody levels in pregnant, lactating, and non-pregnant women, implying that the vaccines work well even during pregnancy.
• Vaccines produced higher antibody levels in pregnant women than did natural infection with Covid-19, implying a greater protection against reinfection.
• Vaccines generated antibodies in umbilical cord blood of babies delivered during the study and in breast milk samples, implying that babies of vaccinated mothers receive some protection against Covid-19.
Vaccine efficacy in pregnancy is also demonstrated by the comparative vaccination rates of hospitalized pregnant women: In Alabama and Texas hospitals, none of the pregnant patients testing positive had been vaccinated pre-Delta, and only 3-6 percent of those testing positive were vaccinated after the rise of Delta.22,23 These low numbers indicate that the vaccines give good protection against hospitalization for infected pregnant women, even with the Delta variant.
What Do Vaccines Do for Baby?
Pregnant mothers and the pro-life movement are especially concerned that the vaccine not harm the baby. However, there is growing evidence that the Covid-19 vaccines are not only safe for mother and baby, they may also protect the baby from Covid after birth.
Multiple studies have now looked at babies who were born after their mothers received the Covid vaccine.53–55 They found that Covid antibodies transfer to the baby via the placenta. These are antibodies that the mother’s body makes in response to the vaccine (not the vaccine components themselves). They flow into the baby’s bloodstream and may help the baby fight Covid if the baby is exposed. This is the same process by which, for example, the pertussis (whooping cough) vaccine that mothers are strongly encouraged to get during pregnancy helps protect the baby for the first several months of life outside the womb.
These studies showed that getting a second dose of the two-dose vaccines contributes to better antibody coverage for the baby (44 percent of mothers with 1 dose had babies with antibodies at birth, compared with 99 percent of mothers with 2 doses). They also showed that the longer gap between receiving the second vaccine dose and birth resulted in more antibodies for the baby. Antibodies are also transferred via breast milk, and evidence suggests that receiving the vaccine while breastfeeding is very safe for both mother and baby.56
More studies will be needed to confirm that antibody transfer from the mother helps babies fight Covid, but I think it is extremely likely based on what we are seeing in adults and what we know from other maternal vaccines. While most infected newborns recover quite well from Covid-19, the added protection of the mother’s vaccination will help reduce the small number of infants who suffer severe or long-term effects from Covid.
Can Pro-Life Groups Support Vaccines with a Connection to Aborted Fetal Cells?
All three vaccines currently approved in the U.S. have a connection to aborted fetal cells: All three were tested on these cells, and the Johnson & Johnson vaccine is manufactured using these cells. What is a pro-life person to do in the face of the clear threat of Covid-19 to life, the safety and efficacy of the vaccines, and their association with abortion?
We know that pro-life people have differing opinions about the morality of the vaccine due to the connection with abortion of the Covid vaccines in use in North America and Europe. Some prolifers have decided to avoid even a remote association with the use of aborted fetal cells by declining the vaccine. However, the approach of the Catholic Church seems to me to be the most consistent and well-thought-out response from a pro-life perspective.57 The conclusion of the Church is that we should always advocate for the development of vaccines with no connection to abortion. When alternatives are available and appropriate, we should choose the vaccine with no or lesser association with abortion. When the threat is serious (and I believe Covid-19 clearly qualifies), and the connection with the original abortion used in developing or testing the vaccine is remote, we should use the vaccines to prevent further loss of life, while exhorting the pharmaceutical companies to turn to ethically unproblematic means of production and testing of vaccines, as they have done with many other vaccines [see “Ethical Vaccines Are Becoming a Reality” by Margaret Brady, also in this issue].
Covid-19 threatens the life and health of pregnant women and their babies, as well as other vulnerable populations not discussed here: older adults, people with pre-existing conditions, the small group of people medically unable to get vaccinated, the poor. The data I have reviewed here indicate that the existing Covid-19 vaccines are safe for pregnant women and their babies and help protect them from hospitalization and death.
While most infected pregnant women and their unborn babies do quite well in well-resourced settings, the data clearly show that a significant minority suffer severe complications and death. These numbers increase dramatically in low-resource settings. Prolifers can help prevent their suffering, as well as the suffering of everyone else affected by the pandemic, by speaking with precision and truthfulness about Covid-19 and its mitigation measures. This has been called a pandemic of disinformation, and prolifers ought to do our part to fight false narratives regarding vaccination, fertility, and pregnancy. We can also practice Covid-19 mitigation measures—including vaccines, masks, and social distancing where appropriate—and encourage others, especially pregnant and nursing mothers, to do the same.
*Short-term side effects are common with these vaccines and are well-known and well-studied. Common short-term side effects include pain, redness, and swelling at the injection site; fatigue, headache, muscle pain, fever, etc. The Johnson & Johnson vaccine has a rare side effect of blood clots (thrombosis with thrombocytopenia syndrome); the CDC now encourages people to choose Moderna or Pfizer when available due to this rare risk. The mRNA vaccines (Moderna and Pfizer) have a small risk of myocarditis (heart inflammation), especially in young men, though this risk is less than the risk of myocarditis from Covid-19 infection. These rare side effects are not considered long-term effects: they generally appear within two weeks of receiving a vaccine. People concerned about these risks due to personal medical history should consult with their physician on which vaccine may be appropriate for them.
NOTES (Users may copy and paste doi numbers into their browser for articles so marked; i.e. doi:10.1016/j.bpobgyn.2021.03.004)
1. Elsaddig M, Khalil A. Effects of the COVID pandemic on pregnancy outcomes. Best Pract Res Clin Obstet Gynaecol. 2021;73(January):125-136. doi:10.1016/j.bpobgyn.2021.03.004
2. Centers for Disease Control and Prevention. Data on COVID-19 during Pregnancy: Severity of Maternal Illness. COVID Data Tracker. Published 2021. Accessed October 18, 2021. https://covid. cdc.gov/covid-data-tracker/#pregnant-population
3. Mendez-Dominguez N, Santos-Zaldívar K, Gomez-Carro S, Datta-Banik S, Carrillo G. Maternal mortality during the COVID-19 pandemic in Mexico: a preliminary analysis during the first year. BMC Public Health. 2021;21(1):1-9. doi:10.1186/s12889-021-11325-3
4. PAHO Director urges countries to prioritize pregnant and lactating women for COVID-19 vaccinations. PAHO. September 2021.
5. United Nations Inter-agency Group for Child Mortality Estimation, You D, Hug L, Mishra A, Blencowe H, Moran A. A Neglected Tragedy: The Global Burden of Stillbirths.; 2020.
6. Desisto CL, Wallace B, Simeone RM, Polen K, Ko JY. Risk for Stillbirth Among Women With and Without COVID-19 at Delivery Hospitalization — United States, March 2020—September 2021. 2021;70(47):1640-1645.
7. Chmielewska B, Barratt I, Townsend R, et al. Effects of the COVID-19 pandemic on maternal and perinatal outcomes: a systematic review and meta-analysis. Lancet Glob Heal. 2021;9:e759-72. doi:https://doi.org/10.1016/ S2214-109X(21)00079-6
8. Cavalcante MB, de Melo Bezerra Cavalcante CT, Cavalcante ANM, Sarno M, Barini R, Kwak-Kim
J. COVID-19 and miscarriage: From immunopathological mechanisms to actual clinical evidence. J Reprod Immunol. 2021;148(June):103382. doi:10.1016/j.jri.2021.103382
9. Cosma S, Carosso AR, Cusato J, et al. Coronavirus disease 2019 and first-trimester spontaneous abortion: a case-control study of 225 pregnant patients. Am J Obstet Gynecol. 2021;224(4):391.e1391.e7. doi:10.1016/j.ajog.2020.10.005
10. Badr DA, Picone O, Bevilacqua E, et al. Severe acute respiratory syndrome coronavirus 2 and pregnancy outcomes according to gestational age at time of infection. Emerg Infect Dis. 2021;27(10):2535-2543. doi:10.3201/eid2710.211394
11. Sills ES, Wood SH. An Experimental Model for Peri-conceptual COVID-19 Pregnancy Loss and Proposed Interventions to Optimize Outcomes. Int J Mol Cell Med. 2020;9(3):180-187. doi:10.22088/ IJMCM.BUMS.9.3.
12. Ferraiolo A, Barra F, Kratochwila C, et al. Report of positive placental swabs for sars-cov-2 in an asymptomatic pregnant woman with covid-19. Med. 2020;56(6):1-9. doi:10.3390/medicina56060306
13. Sharps MC, Hayes DJL, Lee S, et al. A structured review of placental morphology and histopathological lesions associated with SARS-CoV-2 infection. Placenta. 2020;101(June):13-29. doi:10.1016/j.placenta.2020.08.018
14. Husen MF, van der Meeren LE, Verdijk RM, et al. Unique severe covid-19 placental signature independent of severity of clinical maternal symptoms. Viruses. 2021;13(8):1-13. doi:10.3390/ v13081670
15. Kazemi SN, Hajikhani B, Didar H, et al. COVID-19 and cause of pregnancy loss during the pandemic: A systematic review. PLoS One. 2021;16(8 August):1-10. doi:10.1371/journal. pone.0255994
16. Allotey J, Stallings E, Bonet M, et al. Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: Living systematic review and metaanalysis. BMJ. 2020;370. doi:10.1136/bmj.m3320
17. Sankaran D, Nakra N, Cheema R, Blumberg D, Lakshminrusimha S. Perinatal sars-cov-2 infection and neonatal covid-19: A 2021 update. Neoreviews. 2021;22(5):e284-e295. doi:10.1542/ neo.22-5-e1001
18. Mark EG, McAleese S, Golden WC, et al. Coronavirus disease 2019 in pregnancy and outcomes among pregnant women and neonates: A literature review. Pediatr Infect Dis J. 2021;40(5):473-478. doi:10.1097/INF.0000000000003102
19. Lokken EM, Huebner EM, Taylor GG, et al. Disease severity, pregnancy outcomes, and maternal deaths among pregnant patients with severe acute respiratory syndrome coronavirus 2 infection in Washington State. Am J Obstet Gynecol. 2021;225(1):77.e1-77.e14. doi:10.1016/j.ajog.2020.12.1221
20. Deloney D. COVID’s impact on those who don’t have virus: Veteran dies at Houston hospital while waiting for treatment. KHOU. August 27, 2021.
21. Kasehagen L, Byers P, Taylor K, et al. COVID-19—Associated Deaths After SARS-CoV-2 Infection During Pregnancy—.2021;70(47):2020-2022.
22. Seasely AR, Blanchard CT, Arora N, et al. Maternal and Perinatal Outcomes Associated With the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Delta (B.1.617.2) Variant. Obstet Gynecol. Published online 2021. doi:10.1097/AOG.0000000000004607
23. Wang AM, Berry M, Moutos CP, et al. Association of the Delta (B.1.617.2) Variant of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) With Pregnancy Outcomes. Obstet Gynecol. Published online 2021. doi:10.1097/AOG.0000000000004595
24. Adhikari EH, SoRelle JA, McIntire DD, Spong CY. Increasing severity of COVID-19 in pregnancy with Delta (B.1.617.2) variant surge. Am J Obstet Gynecol. Published online 2021. doi:10.1016/j. ajog.2021.09.008
25. ModernaTX Inc. FDA Briefing Document: Moderna COVID-19 Vaccine. Vaccines Relat Biol Prod Advis Comm Meet. Published online 2020. doi:10.32388/5n3l17
26. Pfizer-BioNTech. FDA Briefing Document Pfizer-BioNTech COVID-19 Vaccine. Vaccines Relat Biol Prod Advis Comm Meet. Published online 2020.
27. Pfizer. Pfizer And Biontech Commence Global Clinical Trial To Evaluate Covid-19 Vaccine In Pregnant Women. Published 2021. https://www.pfizer.com/news/press-release/press-release-detail/ pfizer-and-biontech-commence-global-clinical-trial-evaluate
28. Janssen Biotech. FDA Briefing Document: Janssen Ad26.COV2.S Vaccine for the Prevention of COVID-19. Vaccines Relat Biol Prod Advis Comm Meet Relat Biol Prod Advis Comm Meet. Published online 2021. doi:10.1007/s40278-021-99446-z
29. Bowman CJ, Bouressam M, Campion SN, et al. Lack of effects on female fertility and prenatal and postnatal offspring development in rats with BNT162b2, a mRNA-based COVID-19 vaccine. Reprod Toxicol. 2021;103:28-35. doi:10.1016/j.reprotox.2021.05.007
30. Hopkins JS, Toy S. Pfizer Study of Covid-19 Vaccine in Pregnant Women Delayed by Slow Enrollment. The Wall Street Journal. September 22, 2021.
33. Shimabukuro TT, Kim SY, Myers TR, et al. Preliminary Findings of mRNA Covid-19 Vaccine Safety in Pregnant Persons. N Engl J Med. 2021;384(24):2273-2282. doi:10.1056/nejmoa2104983
34. Wainstock T, Yoles I, Sergienko R, Sheiner E. Prenatal maternal COVID-19 vaccination and pregnancy outcomes. Vaccine. 2021;39:6037-6040. doi:10.1016/j.vaccine.2021.09.012
35. Kharbanda EO, Haapala J, Desilva M, et al. SpontaneousAbortion following COVID-19 Vaccination during Pregnancy. JAMA—J Am Med Assoc. 2021;330:10-12. doi:10.1001/jama.2021.15494
36. Magnus MC, Gjessing HK, Eide HN, Wilcox AJ, Fell DB, Håberg SE. Covid-19 Vaccination during Pregnancy and First-Trimester Miscarriage. N Engl J Med. 2021;385(21):2008-2010. doi:10.1056/nejmc2114466
37. Al-Ahmad A. [Sciences/Pharmacokinetics] Do nano-particles of the Pfizer COVID-19 vaccine cross the blood-brain barrier and infect your brain with mRNA (or will fritz your gonads)? Published 2021. Accessed January 7, 2022. https://scientistabe.wordpress.com/2021/05/31/sciencespharmacokinetics-do-nano-particles-of-the-pfizer-covid-19-vaccine-cross-the-blood-brain-barrierand-infect-your-brain-with-mrna-or-will-fritz-your-gonads/
38. Teoh F (editor). COVID-19 vaccines don’t affect ovaries or fertility in general; the vaccines are highly effective at preventing illness and death. Health Feedback. Published 2021. Accessed January 7, 2021. https://healthfeedback.org/claimreview/covid-19-vaccines-dont-affect-ovaries-or-fertilityin-general-the-vaccines-are-highly-effective-at-preventing-illness-and-death/
39. Crawford N. COVID Vaccine Nanoparticles Accumulating in the Ovaries? Published 2021. Accessed January 7, 2022. https://www.nataliecrawfordmd.com/youtube/covid-vaccinenanoparticles-accumulating-in-the-ovaries
40. Baton Rouge General. How Likely are Long-Term Effects of the COVID Vaccine? Baton Rouge General. August 6, 2021.
41. MU Healthcare. How Do We Know the COVID-19 Vaccine Won’t Have Long-Term Side Effects? MU Health. Published 2021. Accessed October 21, 2021. https://www.muhealth.org/ourstories/how-do-we-know-covid-19-vaccine-wont-have-long-term-side-effects
42. Bentov Y, Beharier O, Moav-Zafrir A, et al. Ovarian follicular function is not altered by SARSCoV-2 infection or BNT162b2 mRNA COVID-19 vaccination. Hum Reprod. 2021;36(9):2506-2513. doi:10.1093/humrep/deab182
43. Morris RS, Morris AJ, IL N. Exposure of Ovaries To Covid-19 Vaccination Does Not Impair Fertility. Fertil Steril. 2021;116(3):e473. doi:10.1016/j.fertnstert.2021.08.027
44. Aharon D, Canon CM, Hanley WJ, et al. Mrna Covid-19 Vaccines Do Not Compromise Implantation of Euploid Embryos. Fertil Steril. 2021;116(3):e77. doi:10.1016/j.fertnstert.2021.07.215
45. Gonzalez DC, Nassau DE, Khodamoradi K, et al. Sperm parameters before and after COVID-19 mRNA Vaccination. J Am Med Assoc. 2021;326(3):273-274.
46. Male V. Menstrual changes after covid-19 vaccination. BMJ. 2021;374. doi:10.1136/bmj.n2211
47. Martinez M. COVID-19 NEWS: Study to Investigate Impacts of COVID Vaccines on Menstruation.
Johns Hopkins Med Newsroom. Published online September 2021.
48. Edelman A, Boniface ER, Benhar E, et al. Association between menstrual cycle length and coronavirus disease 2019 (COVID-19) Vaccination. Obstet Gynecol. 2022;00(00):1-9. doi:10.1097/ AOG.0000000000004695
50. ACOG and SMFM Recommend COVID-19 Vaccination for Pregnant Individuals. ACOG. Published 2021. Accessed October 21, 2021. https://www.acog.org/news/news-releases/2021/07/ acog-smfm-recommend-covid-19-vaccination-for-pregnant-individuals
52. Kumar A. Most people can safely get the COVID-19 vaccine. Dear Pandemic.
53. Gray KJ, Bordt EA, Atyeo C, et al. Coronavirus disease 2019 vaccine response in pregnant and lactating women: a cohort study. Am J Obstet Gynecol. 2021;225(3):303.e1-303.e17. doi:10.1016/j. ajog.2021.03.023
54. Mithal LB, Otero S, Shanes ED, Goldstein JA, Miller ES. Cord blood antibodies following maternal coronavirus disease 2019 vaccination during pregnancy. Am J Obstet Gynecol. 2021;225(2):192-194. doi:10.1016/j.ajog.2021.03.035
55. Prabhu M, Murphy EA, Sukhu AC, et al. Antibody Response to Coronavirus Disease 2019 (COVID-19) Messenger RNA Vaccination in Pregnant Women and Transplacental Passage Into Cord Blood. Obstet Gynecol. 2021;138(2):278-280. doi:10.1097/AOG.0000000000004438
56. Hale T, Krutsch K. COVID-19 Vaccine in Pregnancy and Breastfeeding. Infant Risk Center. Published 2021. Accessed October 29, 2021. https://www.infantrisk.com/covid-19-vaccinepregnancy-and-breastfeeding
57. Pontifical Academy for Life. Moral Reflections on Vaccines Prepared from Cells Derived From Aborted Human Foetuses. Published online 2005.
Meaghan Bond holds a PhD in Bioengineering from Rice University, and is a NEST Senior Design Engineer & Lecturer at the Rice360 Institute for Global Health Technologies.