Initial report received on 17 November 2011 via search of the literature. This case involved reports received through 01 March 2010 by the CDC of pregnant women who were vaccinated with the 2009 H1N1 vaccine (trade name, manufacturer name and lot number not reported) during 01 October 2009 through 28 February 2010. Some of these patients (31/294 patients) may have also received a dose of seasonal INFLUENZA vaccine (trade name, manufacturer name and lot number not reported). Non-country reports were excluded. Include in the reports were AEs in neonates of the report indicated their mother had received 2009 H1N1 vaccine during pregnancy. One of those patients was born with congenital anomaly and has been captured in case number 2011-11325. Information regarding that patient's mother has been captured in case number 2011-11324. Regarding this case: Characteristics of the reports (which included all 294 patients that were vaccinated) were received by the CDC of pregnant women vaccinated 01 October 2009 through 28 February 2010: 60/294 reports were serious; 2/294 involved deaths (1 patient died from ruptured aortic aneurysm, and one patient died from hemorrhagic shock. In both cases the neonates were born alive); median maternal age of patients was 30 years of age (age range 15.0-46.0 years); median onset interval for onset of adverse and serious adverse events was 2 days (range 0-84.0 days); Median gestational age (in weeks) at time of vaccinations was 13 weeks (range 3.0-39.0 weeks) with 133/247 patients in the first trimester of pregnancy, 67/247 in the second trimester and 42.247 in the third trimester. Adverse events that had been reported after vaccinations included: Pregnancy-specific outcomes: SAB (121; 41.2%); Stillbirth (19; 6.5%); preterm delivery (7; 2.4 %); threatened abortion (4; 1.4%); preterm labor (3; 1.0%); maternal death (2; 0.7%); preeclampsia (2; 0.7%); intrauterine growth restriction (2; 0.7%); fetal hydronephrosis (1; 0.3%); fetal tachycardia (1; 0.3%); cleft lip (1:0.3%); neonatal intraparenchymal hemorrhage (1; 0.3%); and intrauterine fetal death (1; 0.3%). Non-pregnancy-specific outcomes included allergic reactions other than anaphylaxis (36; 12.2 %); general or constitutional symptoms (28; 9.5%); local reactions (10; 3.4%); paresthesias (8; 2.7%); Bell's Palsy (5; 1.7%); syncope (5; 1.7%); dizziness (5; 1.7%); hypoesthesia (3; 1.0%); headache (3; 1.0%); anaphylaxis (1;0.3%); and other (25; 8.5%, which included anxiety, arthralgia, asthenia, arthritis, blurred vision, chest pain, chronic bronchitis, cough, diarrhea, dyspnea, eye swelling, influenza, influenza-like illness, lip injury, nail bleeding, panic attack, shingles, wheezing, tachycardia, tremors, unusual taste, upper respiratory infection, wheezing). Risk factors for the SABs (which were 95) and stillbirths (which were 18) included advanced maternal age, smoking, history of intrauterine fetal death, hypothyroidism, diabetes mellitus, urinary tract infection, alcohol or drug use, obesity, and "other" (which included chlamydia infection and complicated pregnancy, congenital malformations in past pregnancies, uncontrolled diabetes, chronic hypertension, positive Down Syndrome screening, k chronic hypertension, and macrocytic hyperchromic anemia). Recovery status was not reported for any of the patients. The following is verbatim from the published summary of the article regarding all patients: "Background and Objective: In April 2009, H1N1 virus infection( 2009 H1N1) was identified. The Advisory Committee on Immunization Practices recommended that pregnant women (in any trimester) be included as an initial target group for 2009 H1N1 vaccination. Monitoring adverse events (AEs) following 2009 H1N1 vaccine administration in pregnant woman was a priority for the Centers for Disease Control and Prevention (CDC) in collaboration with the Food and Drug Administration (FDA). Raid surveillance was conducted for adverse events reported to Vaccine Adverse Event Reporting System (VAERS) in pregnant women who received H1N1 vaccines to assess for potential vaccine safety problems. Materials and Methods: The VAERS, established in 1990, is jointly administered by the CDC and FDA. VAERS generally cannot assess whether a vaccination caused an AE but can identify possible vaccines safety problems for further investigation. Reports are classified as serious, based on the Code of Federal Regulations, if they result in death, life-threatening illness, hospitalization or prolongation of hospitalization, permanent disability, or congenital anomaly. As part of the federal response to monitor the safety of 2009 H1N1 vaccine, VAERS was enhanced in several ways. VAERS reports received through March 1, 2010, on pregnant women vaccinated with 2009 H1N1 vaccine from Oct.1, 2009, through Feb. 28, 2010 were analyzed. Included were reports of AEs in neonates if the report indicated that their mothers had received the 2009 H1N1 vaccine during pregnancy. All VAERS reports for pregnant cases were manually reviewed. Medical records were requested for all reports that suggested the vaccinee was pregnant at the time of receipt of the 2009 H1N1 vaccine or that concerned infants born to mothers who had received 2009 H1N1 vaccine during pregnancy. Reporting rated of AEs in pregnant women were calculated by dividing the number of AEs by the estimated number of inactivated 2009 H1N1 vaccines doses administered to pregnant women during the time period were covered in this review. RESULTS: From Oct. 1, 2009, through Feb.28, 2010, VAERS received 294 reports; 288 followed inactivated and 6 followed live vaccines. Sixty reports (20.4%) were coded as serious, including 2 maternal deaths. Serious reports corresponded to 59 pregnant women who were hospitalized for any reason and 1 to an infant born with a congenital anomaly. The 2009 H1N1 vaccine was reported as administered mostly during the first (133; 53.9%) or second trimester of pregnancy (67; 27.1%). The most frequent pregnancy-specific AE reported following 2009 H1N1 vaccine administration was spontaneous abortion (SAB) in 121 women (41.2% of reports), followed by stillbirth in 19 women (6.5% of reports). Ninety-five SABs (78.5%) and 18 stillbirths (94.7%) were verified by review of medical records. Five fetal adverse outcomes were reported. Risk factors for SAB were identified in 47 of the 95 verified reports (49.5%). The most common risk factor was maternal age 35 years or older in 25 (26.3%) reports. Of 18 stillbirths with verified diagnosis, 13 (72.2%) had at least 1 maternal risk factor for stillbirth or a pathologic finding that may have contributed to the fetal demise. The overall reporting rate of AEs to VAERS in pregnant women after inactivated 2009 H1N1 vaccine was 118.2 reports per 1 million pregnant women vaccinated. The reporting rates for SABs and stillbirths were 49.2 and 7.8 reports, respectively, per 1 million pregnant women vaccinated. Table of adverse events (presented in the article) were based on main diagnosis following medical chart review. The events included: Pregnancy-specific outcome of SAB (121; 41.2%); stillbirth (19; 6.5%); preterm delivery (7; 2.4%); threatened abortion (4; 1.4%); preterm labor (3; 1.0%); maternal death (2; 0.7%); preeclampsia (2; 0.7%); intrauterine growth restriction (2; 0.7%); fetal hydronephrosis (1; 0.3%); fetal tachycardia (1; 0.3%); cleft lip (1; 0.3%); neonatal intraparenchymal hemorrhage (1; 0.3%); and intrauterine fetal death (1; 0.3%). Non-pregnancy-specific outcomes included allergic reactions other than anaphylaxis (36; 12.2%); general or constitutional symptoms (28; 9.5%); local reactions (10; 3.4%); paresthesias (8; 2.7%); Bell's Palsy (5; 1.7%); syncope (5; 1.7%); dizziness (5; 1.7%); hypoesthesia (3; 1.0%); headache (3; 1.0%); anaphylaxis (1; 0.3%); and other (25; 8.5%, Includes anxiety, arthralgia, asthenia, asthma, arthritis, blurred vision, chest pain, chronic bronchitis, cough, diarrhea, dyspnea, eye swelling, influenza, influenza-like illness, lip injury, nail bleeding, panic attack, shingles, sneezing, tachycardia, tremors, unusual taste, upper respiratory infection, wheezing). Comment: From October 2009 through February 2010, approximately 3% of reports to VAERS after 2009 H1N1 vaccine were of pregnant women who experienced at least 1 AE after vaccination. Among these 294 reports of AEs, no unusual patterns of adverse maternal or fetal outcomes were observed. The most common pregnancy-specific AE reported was SAB. In the review of medical records, more than an third of women who experienced a SAB had at least 1 risk factor, the most common being advance maternal age. The second most common pregnancy specific AE was stillbirth. Careful review of medical records revealed that 72% of those women had at least 1 risk factor or a pathologic finding in the fetus or placenta, suggesting factors other than vaccination that may have contributed to the fetal demise. SAB is a relatively frequent event in pregnancy, with a rate as high as 22.4% in women aged 34 years or older and 10.4% in women younger than 25 years. Stillbirths occur at a background rate of 0.4% of all pregnancies or 6.22 per 1000 live births and fetal deaths. There is underreporting to VAERS in general and the proportion of AEs following immunization among pregnant women that are reported to VAERS is unknown. Nonetheless, the reporting rates to VAERS for SABs and stillbirths after H1N1 vaccines was several orders of magnitude lower than the expected rates of fetal losses in the general population of pregnant women during a time of heightened awareness about vaccine safety. The VAERS data provided no indication that the occurrence of SAB and stillbirths following INFLUENZA vaccination was higher than in the general population. Other AEs observed in pregnant women were mostly nonserious and were similar to those reported in a preliminary review of the safety of 2009 H1N1 vaccines among the general population. VAERS is a passive surveillance system that may be prone to biased reporting (over-or underreporting) and inconsistency in the quality and completeness of reports. VAERS generally cannot determine whether a vaccine caused an AE. Stimulated reporting can occur following publicity around a potential AE. One important limitation of VAERS is that it collects data only on vaccinated individuals who have experienced an AE. The total vaccinated population is not known with certainty and therefore incidence rates of AE cannot be directly calculated. Review of VAERS reports following 2009 H1N1 vaccination had provided a comprehensive and rapid assessment of the safety of inactivated 2009 H1N1 vaccine among pregnant women during a period when INFLUENZA vaccine coverage during pregnancy was at its highest recorded levels. Clinical Implications: 1) No unusual patterns of adverse maternal or fetal outcomes were observed in pregnant women who received influenza A 2009 monovalent vaccines and who reported to the Vaccine Adverse Event Reporting System (VAERS). 2) The reporting rates of spontaneous abortion and stillbirth were markedly lower than the expected number of fetal losses in the general population of pregnant women, probably because of underreporting in VAERS. 3) VAERS generally cannot assess whether a vaccination caused an adverse event but can identify possible vaccine safety problems for further investigation. 4) Findings in passive surveillance systems such as VAERS need to be interpreted with caution, given their inherent limitations, such as over-underreporting, biased reporting, and inconsistency in quality and completeness of reports." Documents held by sender: None.