Table 1.

Characteristics of reports following hepatitis B vaccination during pregnancy in the Vaccine Adverse Event Reporting System (VAERS), United States, 1990 – 2016

Characteristic
Total reports	192
Reports describing adverse events n (%)	110 (57.3)
Maternal age in years, median (range)a	24 (14 – 41)
Interval from vaccination to adverse event in days, median (range)b	3 (0 – 274)
Gestational age in weeks at time of vaccination, median (range)c	6 (1 – 39)
Serious adverse events, n (%)d	12 (6.3)
Type of reporter, N (%)e
Manufacturer	83 (43.2)
Provider	43 (22.4)
Other	33 (17.2)
Patient/parent	14 (7.3)
Maternal age groups N (%)
14 – 19 years	44 (22.9)
20 – 29 years	71 (36.9)
30 – 41 years	42 (21.9)
Vaccines administered, N(%)f
Only Hepatitis B	99 (51.6)
Hepatitis B + Varicella	40 (20.8)
Hepatitis B + MMR	34 (17.7)
Hepatitis B + Hep A	21 (10.9)
Hepatitis B + HPV4	19 (9.9)
Trimester of pregnancy at time of vaccination (N=115) g, N (%)
First (0 – 13 weeks) h	86 (74.7)
< 8 weeks gestation	53/65 (82%)
≥ 8 weeks gestation	12/65 (18%)
Second (14 – 27 weeks)	18 (15.7)
Third (28+ weeks)	11 (9.6)

^a Maternal age unknown in 30 (15.6%) reports

^b Interval unknown for 16 reports with adverse events

^cGestational age at time of vaccination is unknown for 99 reports

MMR: measles, mumps, rubella; hep A: hepatitis A

^dA report is defined as serious when one of the following is reported: death, life-threatening illness, hospitalization or prolongation of hospitalization, or permanent disability

^eType of reporter unknown in 19 (9.9%) reports

^fHepatitis B vaccines administered include: Engerix (93;46.7%), Recombivax (85;42.7%), no brand name (19;9.6%), Comvax (1;0.5%)

^gNeither trimester nor gestational age was indicated in 77 reports

^hOf 86 reports noting vaccination during the first trimester only 65 provided information on gestational age