No observable influence of COVID-19 inactivated vaccines on pregnancy and birth outcomes in the first trimester of gestation

Figures & data

Figure 1. The process of study cohort formation from the recruited pregnant women.

Table 1. Pregnancy and birth outcomes in unvaccinated and vaccinated subjects.

	COVID-9 vaccination during the first trimester
Pregnancy and birth outcomes	No (n = 2032)	Yes (n = 326)	Total (n = 2358)	P value
Maternal background characteristics
Maternal age at delivery (y)	27.9	30.85	28.3	<0.01
Education, ≥ 12 (y)	998 (49.1)	185 (56.7)	1183 (50.2)	0.01
Obesity	203 (10.0)	34 (10.4)	228 (9.7)	0.81
Exposure to primigravida	1068 (52.6)	145 (44.5)	1213 (51.4)	<0.01
Pregnancy complications diagnosed in late pregnancy
Pregnancy-related hypertensive disorders	107 (5.3)	19 (5.8)	126 (5.3)	0.68
Gestational diabetes mellitus	130 (6.4)	23 (7.1)	153 (6.5)	0.66
Oligohydramnios	58 (2.9)	11 (3.4)	69 (2.9)	0.61
Polyhydramnios	54 (2.7)	8 (2.5)	62 (2.6)	0.83
Pathological fetal positions	67 (3.3)	12 (3.7)	79 (3.4)	0.72
Meconium-stained amniotic fluid	89 (4.4)	14 (4.3)	103 (4.4)	0.96
Delivery and postpartum characteristics
Gestational age <37 week	229 (11.3)	40 (12.3)	269 (11.4)	0.60
Cesarean delivery	701 (34.5)	128 (39.3)	829 (35.2)	0.09
Forceps delivery	22 (1.1)	5 (1.5)	27 (1.1)	0.48
Postpartum hemorrhage ≥1000 ml	70 (3.4)	12 (3.7)	82 (3.5)	0.72
Newborn characteristics
Apgar score < 7 at 5 min	20 (1.0)	6 (1.8)	26 (1.1)	0.17
Low birth weight (<2500 g)	19 (0.9)	6 (1.8)	25 (1.2)	0.14
Newborn respiratory complications	32 (1.6)	7 (2.1)	39 (1.7)	0.45
Stillbirth or neonatal death Major structural birth defects	0 (0.0) 31 (1.5)	0 (0.0) 7 (2.1)	0 (0.0) 38 (1.6)	0.41

Table 2. List of major structural birth defects occurring in subjects unvaccinated (no) and vaccinated with COVID-19 inactivated vaccines (yes).

Major structural birth defects	No (n = 31)	Yes (n = 7)
Atrial septal defect	10	2
Ventricular septal defect	5	2
Patent ductus arteriosus	1	0
Fallot’s tetrad	1	0
accessory earlobe malformation	6	1
Cleft lip and palate	1	0
Polydactyly	1	1
Hypospadias	3	1
strephenopodia	1	0
Syndactyly	1	0
forearm Dysplasia	1	0

Table 3. Odds ratios for COVID-19 inactivated vaccine exposure regarding miscarriage or ongoing pregnancy.

Subjects’ vaccination status	Number of ongoing pregnancies	Number of miscarriages	Odds ratio (95% CI) *
Unvaccinated	2032	237	Reference
Vaccinated	326	40	0.95 (0.67–1.36)

Data availability statement

The datasets that support the findings of this study are managed by Suzhou Municipal Health Commission and can be requested from the corresponding author upon reasonable request.