Risk factors associated with preterm birth after a prior term delivery.

OBJECTIVE: The objective of this study was to assess the presence of newly acquired preterm birth (PTB) risk factors among primiparous women with no prior history of PTB. DESIGN: Case-control study. SETTING: Deliveries occurring within a large healthcare system from 2002 to 2012. POPULATION: Women with their first two consecutive pregnancies carried to ≥20(0/7)  weeks' gestation. METHODS: Those delivering the first pregnancy at term and the second preterm ≥20(0/7) and <37(0/7)  weeks (term-preterm cases) were compared with women with a term birth in their first two pregnancies (term-term controls). Social factors with the potential to change between the first and second pregnancies and intrapartum labour characteristics in the first pregnancy were compared between cases and controls. MAIN OUTCOME MEASURES: Risk factors for term-preterm sequence. RESULTS: About 38 215 women met inclusion criteria; 1353 (3.8%) were term-preterm cases. Cases and controls were similar with regard to race/ethnicity and maternal age at the time of the first and second deliveries. Cases delivered their second pregnancy approximately 3 weeks earlier (35.7 versus 39.1, P < 0.001). In multivariable models accounting for known PTB risk factors, women with a caesarean delivery in the first pregnancy [adjusted odds ratio (aOR) = 2.20; 95% confidence interval (CI) 1.57-3.08], new tobacco use (aOR = 2.33; 95% CI 1.61-3.38), and an interpregnancy interval <18 months (aOR = 1.37; 95% CI 1.21-1.55) were at increased risk of term-preterm sequence. CONCLUSION: Caesarean delivery in the first pregnancy, new tobacco use, and short interpregnancy interval <18 months are significant risk factors for term-preterm sequence. Women should receive postpartum counselling regarding appropriate interpregnancy interval and cessation of tobacco use. TWEETABLE ABSTRACT: Caesarean delivery in the 1st pregnancy is a significant risk factor for preterm birth following a term delivery.

Continued early onset group B streptococcal infections in the era of intrapartum prophylaxis.

OBJECTIVE: The objective of the study was to determine the rate of early onset group B streptococcus (EOGBS) infection in Utah and identify potential areas of failure in EOGBS prevention. STUDY DESIGN: We queried the microbiology records of Intermountain Healthcare for infants with culture-confirmed EOGBS between 1 January 2002 and 31 May 2006 and calculated rates of EOGBS per 1000 deliveries. We reviewed the infant and maternal records of each EOGBS case to identify possible failures in EOGBS prevention. RESULT: There were 54 cases of EOGBS among the 127 205 births (0.42/1000 births). Of all, 12 were preterm. Of the 39 (93%) women prenatally screened for GBS, 31 (79%) had negative results and 7/8 (88%) women with positive prenatal GBS screens either did not receive intrapartum antibiotic prophylaxis (IAP) or received inadequate IAP. Of the 54 infants with EOGBS, 3 (6%) died. CONCLUSION: Utah's rates of EOGBS were higher than the national average. Factors associated with EOGBS include missed screening opportunities, inadequate IAP, and false-negative maternal GBS culture.

Comparison of a commercial reversed passive latex agglutination assay to an enzyme immunoassay for the detection of Shiga toxin-producing Escherichia coli.

A multicenter study was performed to compare the performance of a prototypic reversed passive latex agglutination assay (VTEC Screen "Seiken"; Denka-Seiken, Japan) with the Premier EHEC Enzyme Immunoassay (Meridian Diagnostics, USA) for the detection of Shiga toxin in 554 diarrheal stool samples. Standard culture on sorbitol MacConkey agar and the use of latex agglutination reagents were included to identify the Escherichia coli O157, O26 and O111 serotypes. There was 99% agreement between the VTEC screen and enzyme immunoassay (kappa=0.823). Seventeen samples were positive for toxin by one or both assays. One toxin-positive sample using the enzyme immunoassay and four positive samples using the VTEC Screen could not be confirmed. Serotypes identified included: O157:H7 (n=8), O26 (n=2), O111 (n=1) and O45:H2 (n=1). The VTEC screen is easy to perform and comparable to the Meridian EHEC test for detection of Shiga toxin in clinical samples.

Susceptibility of beta-hemolytic streptococci to nine antimicrobial agents among four medical centers in Salt Lake City, Utah, USA.

A multicenter study was performed to evaluate the susceptibility of beta-hemolytic streptococci to nine antimicrobial agents. MICs were performed in cation-supplemented Mueller-Hinton broth with 3.5% lysed sheep red blood cells according to NCCLS guidelines. A total of 646 isolates were tested: 300 (46%) group A; 170 (26%) group B; 38 (6%) group C, 35 (5%) group F; 83 (17%) group G; and 20 (3%) nongroupable. Six percent of the total isolates were resistant to one or more of the antibiotics tested. Approximately 7% of 387 strains from the University of Utah Hospital and Clinics were resistant to erythromycin. Four isolates were resistant to clindamycin. Six strains (3%) from Primary Children's Medical Center (207 tested) were resistant to one or more of the macrolides. Resistance was rare at the LDS Hospital and the Salt Lake Veteran's Affairs Hospital. Overall, resistance among beta-hemolytic streptococci in this geographic location does not seem to be a significant problem, except at the tertiary care university hospital.