Table 4 Timing and adverse effects of mRNA vaccination

Inoculation timing

 First trimester

18.7 (156/834)

8.2 (68/834)

 Second trimester

61.8 (515/834)

58.2 (485/834)

 Third trimester

18.1 (151/834)

31.4 (262/834)

 Unvaccinated

0.0 (0/834)

1.1 (9/834)

 Unknown

1.4 (12/834)

1.2 (10/834)

Adverse reactions (multiple answers)

 Headache

18.5 (153/828)

33.4 (274/820)

 < 0.001

 Malaise

46.3 (383/828)

66.1 (543/822)

 < 0.001

 Dizziness

2.8 (23/828)

6.2 (51/819)

 < 0.001

 Fever (> 37.5 ℃)

12.7 (105/827)

33.0 (271/820)

 < 0.001

 Cold

8.2 (68/828)

23.9 (196/821)

 < 0.001

 Nausea

3.4 (28/828)

6.6 (54/820)

0.003

 Pain at injection site

90.0 (745/828)

81.0 (665/821)

 < 0.001

 Breathing difficulty

0.61 (5/825)

17.1 (14/821)

0.037

 Thrombosis

0.12 (1/825)

0.12 (1/818)

0.993

 Anaphylaxis

0.12 (1/827)

0.12 (1/820)

0.997

Treatment for adverse reactions

0.12 (1/827)

0.37 (3/818)

0.311