Thank you to Professor Jim Thornton, professor of Obstetrics and Gynaecology in Nottingham, author and NHS consultant, for permission to post his primary source research and case report updates here.

All material is copied with permission; use of the first person refers to Dr Thornton.

You can follow Dr Thornton on Twitter.

Primary Sources

Primary scientific reports of clinical data on the safety and effectiveness of SARS-CoV-2 vaccines in pregnancy, and in women of childbearing age. In reverse order. Regularly updated. Click here for ripe-tomato.org’s Covid-19 navigation page.

Update 7 April – source 7 update.

Update 2 April – source 21 added

Source 21 – 27 vaccinated women from USA

Twenty seven vaccinated women who delivered at Prentice Women’s Hospital in Chicago, (January-March 2021) (click here or source). 25/28 (one set of twins) infants had positive cord IgG. The exact vaccine is not reported but the authors note that at the time Pfizer/BioNTech and Moderna/NIH were available. Citation: MITHAL LB, OTERO S, SHANES ED, GOLDSTEIN JA, MILLER ES, Cord Blood Antibodies following Maternal COVID-19 Vaccination During Pregnancy, American Journal of Obstetrics and Gynecology (2021), doi: https://doi.org/10.1016/j.ajog.2021.03.035.

Update 2 April source 20 added

Source 20 – 27 vaccinated women from USA

Twenty seven vaccinated women who delivered at Prentice Women’s Hospital in Chicago, (January-March 2021) (click here or source). 25/28 (one set of twins) infants had positive cord IgG. The exact vaccine is not reported but the authors note that at the time Pfizer/BioNTech and Moderna/NIH were available. Citation: MITHAL LB, OTERO S, SHANES ED, GOLDSTEIN JA, MILLER ES, Cord Blood Antibodies following Maternal COVID-19 Vaccination During Pregnancy, American Journal of Obstetrics and Gynecology (2021), doi: https://doi.org/10.1016/j.ajog.2021.03.035.

Update 17 March – source 19 added

Source 19 – 20 vaccinated women from Israel

This MedRxiv preprint reports 20 pregnant women who received two doses of the Pfizer/BioNTech vaccine in late pregnancy in February 2021 (click here or 2021.03.11.21253352v1.full). All women efficiently transferred antibodies to the fetus. They were cared for at Hadassah Medical Center in Jerusalem. Citation: Amihai Rottenstreich, Gila Zarbiv, Esther Oiknine-Djian, Roy Zigron, Dana G. Wolf, Shay Porat. Efficient maternofetal transplacental transfer of anti- SARS-CoV-2 spike antibodies after antenatal SARS-CoV-2 BNT162b2 mRNA vaccination medRxiv 2021.03.11.21253352; doi: https://doi.org/10.1101/2021.03.11.21253352

Update 10 March – sources 15 to 18 added

Source 18 – 6 postnatal vaccinated women in USA

The MedRxiv preprint describes six lactating women who received both doses of the Pfizer-BioNTech or Moderna vaccine between December 2020 and January 2021 (click here or 2021.02.23.21252328v1.full). They all developed IgA and IgG antibodies in breast milk within seven says. They were cared for at Providence Portland Medical Center, Oregon. Citation: Jill K. Baird, Shawn M. Jensen, Walter J. Urba, Bernard A. Fox, Jason R. Baird SARS-CoV-2 antibodies detected in human breast milk post-vaccination. medRxiv 2021.02.23.21252328; doi: https://doi.org/10.1101/2021.02.23.21252328

Source 17 – case report of 3rd trimester vaccination from USA

A 34-year-old woman received the Pfizer-BioNTech, mRNA vaccine at 32 weeks (click here or 13224_2021_Article_1436). The birth was uncomplicated and the baby had cord blood antibodies. The hospital is unnamed, but the authors were from University of Minnesota, Minneapolis. This is the first peer reviewed report of vaccination in pregnancy. Citation: Gill L, Jones CW. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Antibodies in Neonatal Cord Blood After Vaccination in Pregnancy. Obstet Gynecol. 2021 Mar 8. doi: 10.1097/AOG.0000000000004367. Epub ahead of print. PMID: 33684922.

Source 16 – 10 nursing mothers vaccinated in Israel

This MedRxiv preprint describes ten nursing mothers who received the Pfizer-BioNTech mRNA vaccine (click here or 2021.03.06.21252603v1.full). Clinical details and exact vaccine timings in supplementary table 1 (click here or media-1) From author affiliations the women were probably cared for at Lis Maternity & Women’s Hospital, Tel Aviv. Citation: Michal Rosenberg Friedman, Aya Kigel, Yael Bahar, Yariv Yogev, Yael Dror, Ronit lubetzky, Ariel Many, Yariv Wine BNT162b2 COVID-19 mRNA vaccine elicits a rapid and synchronized antibody response in blood and milk of breastfeeding women medRxiv 2021.03.06.21252603; doi: https://doi.org/10.1101/2021.03.06.21252603

Source 15 – 131 reproductive-age vaccine recipients from USA

This MedRxiv preprint includes 84 pregnant, 31 lactating, and 16 non-pregnant women who received either the Pfizer/BioNTech or Moderna mRNA vaccines (click here or 2021.03.07.21253094v1.full). From author affiliations the hospitals were probably Massachusetts General Hospital, and Brigham and Women’s Hospital, both in Boston, Massachussetts. Citation: Kathryn J Gray, Evan A Bordt, Caroline Atyeo, Elizabeth Deriso, Babatunde Akinwunmi, Nicola Young, Aranxta Medina Baez, Lydia L Shook, Dana Cvrk, Kaitlyn James, Rose De Guzman, Sara Brigida, Khady Diouf, Ilona Goldfarb, Lisa M Bebell, Lael M Yonker, Alessio Fasano, Sayed A Rabi, Michal A Elovitz, Galit Alter, Andrea G Edlow COVID-19 vaccine response in pregnant and lactating women: a cohort study medRxiv 2021.03.07.21253094; doi: https://doi.org/10.1101/2021.03.07.21253094

Update 6 March – sources 13 and 14 added. (We do not plan to update these unless the links change).

Source 14 – UK Yellow card reports for COVID-19 vaccine AstraZeneca

Available here. The latest (25 Feb) report (click here or COVID-19_AstraZeneca_Vaccine_Analysis_Print) included 1 vaccine exposure before pregnancy, 30 during pregnancy and 9 postnatal (p 23). The adverse events included 4 spontaneous abortions, 1 or 2 preterm births, and ten cases of morning sickness (p 41). This was out of 42,917 reports, of 157,637 reactions, of which 244 were fatal. Readers should note that “Conclusions on the safety and risks of the vaccines cannot be made on the data shown in the Print alone” and “The overall safety experience with both vaccines is so far as expected from the clinical trials.”  https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/966183/COVID-19_AstraZeneca_Vaccine_Analysis_Print.pdf Accessed 6 March (Not updated unless links change)

Source 13 – UK Yellow Card reports for COVID-19 mRNA Pfizer- BioNTech vaccine

Available here. The latest (4th March) report (click here or COVID-19_mRNA_Pfizer-_BioNTech_Vaccine_Analysis_Print__2_) included 1 vaccine exposure before pregnancy, 37 during pregnancy and 9 postnatal (p 24). The adverse events included 16 spontaneous abortions, 2 or 3 preterm births, and four cases of morning sickness (p 42). This was out of 29,715 reports, of 85,179 reactions, of which 212 were fatal. Readers should note that “Conclusions on the safety and risks of the vaccines cannot be made on the data shown in the Print alone” and “The overall safety experience with both vaccines is so far as expected from the clinical trials.” https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/966631/COVID-19_mRNA_Pfizer-_BioNTech_Vaccine_Analysis_Print__2_.pdf Accessed 6 March. (Not updated unless links change)

Update 28 Feb – sources 11 and 12 added

Source 12 – Janssen register trial of Ad26.COV2.S in pregnancy

Janssen have registered an RCT of the vaccine Ad26.COV2.S in pregnant women (click here). Planned sample size 824. Anticipated primary completion date January 16, 2023

Source 11 – Pfizer/BioNTech register trial of BNT162b2 in pregnancy

Pfizer/BioNTech have registered an RCT of the vaccine BNT162b2 in pregnant women (click here). Planned sample size 4,000. Estimated primary completion date January 8, 2023

Update 24 Feb – source 10 added

Source 10 – Janssen Ad26.COV2.S Vaccine FDA briefing document

See p 52 for pregnancy data (click here or VRBPAC-02.26.21-Meeting-Briefing-Document-FDA). “Eight pregnancies were reported through January 22, 2021 (4 vaccine, 4 placebo). In 7 participants (3 vaccine, 4 placebo) vaccination was within 30 days after LMP, and in 1 vaccine recipient vaccination was prior to LMP. Unsolicited AEs related to pregnancy include spontaneous abortion (1 vaccine, 0 placebo), incomplete abortion (0 vaccine, 1 placebo), elective abortion (0 vaccine, 2 placebo) and ectopic pregnancy (1 vaccine, 0 placebo). Among participants in the vaccine group, two pregnancies are ongoing with outcomes unknown at this time.” Note: Janssen is a subsidiary of Johnson & Johnson, and the Ad26.COV2.S vaccine is usually referred to in the press as the “Johnson & Johnson vaccine”. Citation: Vaccines and Related Biological Products Advisory Committee Meeting. February 26, 2021. FDA Briefing Document. Janssen Ad26.COV2.S Vaccine for the Prevention of COVID-19. Accessed 24 Feb 2021 https://www.fda.gov/media/146217/download

Update 21 Feb – Source 9 added – special HT Keelin O’Donogue. One out of 31,000 vaccinations!

Source 9 – one pregnant woman tested positive following vaccination

This preprint reports 31,069 people who received at least one dose of a COVID-19 vaccine via the Mayo Clinic health system, in Arizona, Florida, Minnesota, or Wisconsin, between December 1^st 2020 and February 8^th 2021. Of the 263 who subsequently received a positive PCR test, one (0.4%) was pregnant (table 3) (click here or Pawlowski pre print). In a propensity matched cohort of 2,630 unvaccinated individuals who also tested positive, seven (0.3%) were pregnant. Citation: Colin Pawlowski, Patrick Lenehan, Arjun Puranik, Vineet Agarwal, AJ Venkatakrishnan, Michiel J.M. Niesen, John C. O’Horo, Andrew D. Badley, John Halamka, Venky Soundararajan. FDA-authorized COVID-19 vaccines are effective per real-world evidence synthesized across a multi-state health system. medRxiv 2021.02.15.21251623; doi: https://doi.org/10.1101/2021.02.15.21251623 

Update 20 Feb – Source 8 added

Source 8 – 15,131 post vaccine pregnancies reported to V-safe

Up to 20 January 8,633 pregnancies related to, or following, the Pfizer-BioNTech vaccine and 6,498 after the Moderna vaccine had been self-reported to the CDC using the V-safe vaccine tracker (click here or 06-COVID-Shimabukuro). Over the same period nearly 22m people had received at least one vaccine dose, and 2M had registered with the V-safe vaccine tracker.  As of January 22nd, 227 pregnancies had also been enrolled in the V-safe pregnancy registry. Citation: Advisory Committee on Immunization Practices (ACIP): COVID-19 vaccine Safety update—January 2021 (slide deck)

Update 6 Feb – source 7 added

Source 7 – IgG in cord blood post SARS-CoV-2 vaccine

This Medxiv preprint reports detection of anti-SARS-CoV-2 IgG in a baby whose mother had received the Moderna mRNA COVID-19 vaccine three weeks prior to birth (click here or 2021.02.03.21250579v1.full). The baby was healthy, with normal newborn nursery course and subsequent well-infant evaluation. The hospital is unnamed but the authors were affiliated with Charles E. Schmidt College of Medicine, Boca Raton, Florida. Citation: Paul D Gilbert, Chad A Rudnick. Newborn antibodies to SARS-CoV-2 detected in cord blood after maternal vaccination. medRxiv 2021.02.03.21250579; doi: https://doi.org/10.1101/2021.02.03.21250579 

Update 7 April. Peer reviewed paper published in BMC Pediatrics (click here or source). Citation: Paul G, Chad R. Newborn antibodies to SARS-CoV-2 detected in cord blood after maternal vaccination – a case report. BMC Pediatr. 2021 Mar 22;21(1):138. doi: 10.1186/s12887-021-02618-y. PMID: 33752624; PMCID: PMC7982334.

Update 25 Jan – source 6 added

Source 6 – Astra Zeneca/Oxford. Safety & Efficacy report, Lancet

The supplementary appendix of the interim safety and efficacy report of four trials of the Astra Zeneca/Oxford (ChAdOx1 nCoV-19) vaccine reports one spontaneous abortion in the intervention group and one in the control group. For main paper (click here or PIIS0140673620326611) appendix (here or mmc1). These cases are presumably included in Source 3. Citation: Voysey M, Clemens SAC, Madhi SA, Weckx LY, Folegatti PM, Aley PK, Angus B, Baillie VL, Barnabas SL, Bhorat QE, Bibi S, Briner C, Cicconi P, Collins AM, Colin-Jones R, Cutland CL, Darton TC, Dheda K, Duncan CJA, Emary KRW, Ewer KJ, Fairlie L, Faust SN, Feng S, Ferreira DM, Finn A, Goodman AL, Green CM, Green CA, Heath PT, Hill C, Hill H, Hirsch I, Hodgson SHC, Izu A, Jackson S, Jenkin D, Joe CCD, Kerridge S, Koen A, Kwatra G, Lazarus R, Lawrie AM, Lelliott A, Libri V, Lillie PJ, Mallory R, Mendes AVA, Milan EP, Minassian AM, McGregor A, Morrison H, Mujadidi YF, Nana A, O’Reilly PJ, Padayachee SD, Pittella A, Plested E, Pollock KM, Ramasamy MN, Rhead S, Schwarzbold AV, Singh N, Smith A, Song R, Snape MD, Sprinz E, Sutherland RK, Tarrant R, Thomson EC, Török ME, Toshner M, Turner DPJ, Vekemans J, Villafana TL, Watson MEE, Williams CJ, Douglas AD, Hill AVS, Lambe T, Gilbert SC, Pollard AJ; Oxford COVID Vaccine Trial Group. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Lancet. 2021 Jan 9;397(10269):99-111. doi: 10.1016/S0140-6736(20)32661-1. Epub 2020 Dec 8. Erratum in: Lancet. 2021 Jan 9;397(10269):98. PMID: 33306989; PMCID: PMC7723445.

Update 18 Jan – source 5 added

Source 5 – BioNTech/Pfizer. Safety and Efficacy report, NEJM

The Safety and Efficacy report of the phase 2/3 placebo controlled trial of the BioNTech/Pfizer (BNT162b2 mRNA) Covid-19 Vaccine (click here or nejmoa2034577) includes four pregnancies in the vaccine group and five in controls. These will overlap with those in studies 1 and 4.  Citation; Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, Perez JL, Pérez Marc G, Moreira ED, Zerbini C, Bailey R, Swanson KA, Roychoudhury S, Koury K, Li P, Kalina WV, Cooper D, Frenck RW Jr, Hammitt LL, Türeci Ö, Nell H, Schaefer A, Ünal S, Tresnan DB, Mather S, Dormitzer PR, Şahin U, Jansen KU, Gruber WC; C4591001 Clinical Trial Group. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med. 2020 Dec 31;383(27):2603-2615. doi: 10.1056/NEJMoa2034577. Epub 2020 Dec 10. PMID: 33301246; PMCID: PMC7745181.

Update 15 Jan – source 4 added

Source 4 – Comirnarty. EMA Assessment report

See p 109 for pregnancy data (click here or comirnaty-epar-public-assessment-report_en). Comirnarty is the EU name for the BioNTech/Pfizer vaccine. The data therefore likely overlap with Source 1. Citation: European Medicines Agency. 21 December 2020. EMA/707383/2020. Committee for Medicinal Products for Human Use (CHMP). Assessment report. Comirnaty. Common name: COVID-19 mRNA vaccine (nucleoside-modified) Procedure No. EMEA/H/C/005735/0000. Accessed 14 January 2021. https://www.ema.europa.eu/en/documents/assessment-report/comirnaty-epar-public-assessment-report_en.pdf 

Update 14 Jan – Sources 1-3 added

Source 3 – Astra Zeneca/Oxford. MHRA public assessment report

See p 48 onward for pregnancy data (click here or UKPAR_COVID_19_Vaccine_AstraZeneca_05.01.2021). Citation: Medicines and Healthcare products Regulatory Agency. Public Assessment Report. Authorisation for Temporary Supply. COVID-19 Vaccine AstraZeneca, solution for injection in multidose container COVID-19 Vaccine (ChAdOx1-S [recombinant]). Department of Health and Social Care (DHSC) AstraZeneca AB. Accessed January 14 2021. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/949772/UKPAR_COVID_19_Vaccine_AstraZeneca_05.01.2021.pdf 

Source 2 – Moderna. FDA briefing document

See p 44 onward for pregnancy data (click here or VRBPAC-12.17.20-Meeting-Briefing-Document-FDA_0). Citation: U.S. Food and Drug Administration. Vaccines and Related
Biological Products Advisory Committee meeting—December 17, 2020—FDA briefing document—Moderna COVID-19 vaccine. Accessed January 14, 2021. https://www.fda.gov/media/144434/download

Source 1 – BioNTech/Pfizer. FDA briefing document

See p 42 onwards for pregnancy data (click here or VRBPAC-12.10.20-Meeting-Briefing-Document-FDA). Citation: U.S. Food and Drug Administration. Vaccines and Related Biological Products Advisory Committee Meeting, December 10, 2020. FDA Briefing Document. Pfizer-BioNTech COVID-19 Vaccine. Accessed January 14 2021. https://www.fda.gov/media/144245/download 

Jim Thornton