# COVID‐19 and Pregnancy: Key Findings

**Authors:** Gabrielle Gimenes Lima, Ana Flávia Segati, Giovanna Santos Oliveira, Nicoly Simões de Melo, Túlio Nakazato da Cunha, Elizabeth De Gaspari

PMC · DOI: 10.1111/sji.70109 · 2026-03-25

## TL;DR

This paper reviews how pregnancy affects COVID-19 outcomes and how maternal vaccination protects newborns through antibody transfer.

## Contribution

The paper provides a synthesis of maternal SARS-CoV-2 infection risks and the protective effects of vaccination during pregnancy.

## Key findings

- Symptomatic maternal COVID-19 increases risks of severe outcomes, but vertical transmission is rare.
- Maternal vaccination induces strong IgG responses and efficient antibody transfer to newborns.
- Placental pathology involves maternal vascular malperfusion and inflammation, with limited direct viral infection.

## Abstract

Pregnant individuals were prioritised for COVID‐19 research due to concerns about increased susceptibility and limited clinical trial data. This narrative review synthesises evidence on maternal infection, immunological adaptations, placental susceptibility, and antibody transfer following maternal SARS‐CoV‐2 vaccination. Symptomatic COVID‐19 during pregnancy increases risks of severe outcomes, whereas vertical transmission remains rare. Placental pathology is characterised mainly by maternal vascular malperfusion and inflammation, with limited evidence of direct viral infection. Maternal vaccination—particularly with mRNA vaccines—induces robust IgG responses with efficient transplacental and lactational transfer, conferring passive neonatal protection. Key uncertainties include optimal vaccine timing, durability of neonatal immunity, and variant‐specific responses. Strengthening standardised research and ensuring inclusion of pregnant individuals is essential for global maternal health policy.

Mechanistic overview of maternal SARS‐CoV‐2 immunisation, affinity‐matured IgG production, FcRn‐mediated transplacental IgG transport, and antibody delivery to the newborn via fetal circulation and breast milk. The schematic also highlights the translational relevance of murine models, which share conserved mechanisms of antibody induction despite structural differences in placental architecture.

## Linked entities

- **Proteins:** IGG (Immunoglobulin G level), FCGRT (Fc gamma receptor and transporter)
- **Diseases:** COVID-19 (MONDO:0100096)
- **Species:** Mus musculus (taxon 10090)

## Full-text entities

- **Genes:** Fcgrt (Fc fragment of IgG receptor and transporter) [NCBI Gene 14132] {aka FcRn}, FCGRT (Fc gamma receptor and transporter) [NCBI Gene 2217] {aka FCRN, FcgammaRn, alpha-chain}, CD79A (CD79a molecule) [NCBI Gene 973] {aka IGA, IGAlpha, MB-1, MB1}, DPP4 (dipeptidyl peptidase 4) [NCBI Gene 1803] {aka ADABP, ADCP2, CD26, DPPIV, TP103}, TNF (tumor necrosis factor) [NCBI Gene 7124] {aka DIF, IMD127, TNF-alpha, TNFA, TNFSF2, TNLG1F}, Ighv1-62 (immunoglobulin heavy variable 1-62) [NCBI Gene 668542] {aka IgG, IgM, IgVH, Igh}, CTSL (cathepsin L) [NCBI Gene 1514] {aka CATL, CTSL1, MEP}, TMPRSS2 (transmembrane serine protease 2) [NCBI Gene 7113] {aka PRSS10}, ACE2 (angiotensin converting enzyme 2) [NCBI Gene 59272] {aka ACEH}, HTC2 (hypertrichosis 2 (generalized, congenital)) [NCBI Gene 3342] {aka CGH, CXINSq27.1, HCG}, IL6 (interleukin 6) [NCBI Gene 3569] {aka BSF-2, BSF2, CDF, HGF, HSF, IFN-beta-2}
- **Diseases:** infectious diseases (MESH:D003141), fatigue (MESH:D005221), respiratory complications (MESH:D012140), anxiety (MESH:D001007), COVID-19 (MESH:D000086382), Inflammatory (MESH:D007249), viral infection (MESH:D014777), inflammatory infiltrates (MESH:D017254), placental dysfunction (MESH:D010922), Maternal Infection (MESH:D007239), preterm birth (MESH:D047928), maternal disease (MESH:D000079262)
- **Chemicals:** progesterone (MESH:D011374)
- **Species:** Homo sapiens (human, species) [taxon 9606], Mus musculus (house mouse, species) [taxon 10090], Severe acute respiratory syndrome coronavirus 2 (no rank) [taxon 2697049]

## Figures

5 figures with captions in the complete paper: https://tomesphere.com/paper/PMC13018292/full.md

---
Source: https://tomesphere.com/paper/PMC13018292