I’m not sure you first dash is correct.
See Table S4. (Help needed)
Here: https://www.nejm.org/doi/suppl/10.1056/NEJMoa2104983/suppl_file/nejmoa2104983_appendix.pdf
It looks like this table says (including the notes) that 37 out of the 81 first trimester vax moms that had completed pregnancy, had miscarriages. (About twice the expected rate of miscarriage)
Your interpretation please...
Characteristics of reports to VAERS among pregnant persons following mRNA COVID-19 vaccines, December 14,2020–February 28, 2021 (N=221)*.
Median maternal age in years (range)
Trimester of pregnancy at time of vaccination in completed weeks†
First (0–13 weeks) Second (14–27 weeks) Third (28+ weeks)
Vaccine brand (%)
Pfizer-BioNTech Moderna
Most frequently reported nonpregnancy-specific adverse events (%)‡ Fatigue
Headache
Chills
Pain in extremity Nausea
Pain
Fever
Injection site pain Dizziness
Injection site erythema
Pregnancy- or neonatal- specific conditions (%)
Miscarriage§
Stillbirth
Premature rupture of membranes
Vaginal bleeding
Fetal hydrops
Preterm delivery
Neonatal death in 22-week preterm birth║ Other¶
33 (16–51)
163
81 (49.7) 53 (32.5) 29 (17.8)
130 (58.8) 90 (40.7)
155 (70.1)
44
43
30
27
25
21
18
17
17
11
66 (29.9)
46 3 3 3 2 2 1 6
* Reports received and processed through February 28, 2021; 1 report with unknown vaccine brand
† Includes 163 reports where information was available on trimester of pregnancy at the time of vaccination
‡ Not mutually exclusive; more than one adverse event can be assigned to a single report
§ 37 in first trimester, 2 in second trimester, and 7 where trimester was unknown or not reported
║ Person was diagnosed with COVID-19 before pregnancy (mild 3-day illness 8 months before delivery) and received dose 2 of Pfizer-BioNTech vaccine one day prior to delivery; onset of
8
preterm labor symptoms began 2 days before dose 2 and birth occurred 32 hours after dose 2 at 22 weeks and 2 days; reported symptoms following receipt of dose 2 were muscle aches and chills; additional information regarding any adverse events associated with dose 1 of the vaccine were not available
¶ Other pregnancy- or neonatal-specific conditions include 1 report each of calcified placenta, leakage of amniotic fluid, shortened cervix, gestational diabetes, pre-eclampsia, irregular/painful contractions
You are mixing VAERS report data with study data.