A novel schistosome species hosted by Planorbella (Helisoma) trivolvis is the most widespread swimmer's itch-causing parasite in Michigan inland lakes.

Cercarial dermatitis ('swimmer's itch'; SI), characterized by small itchy bumps caused by schistosome parasites of birds and mammals, is a common problem in Michigan. Research on avian schistosomes began nearly 100 years ago in Michigan inland lakes, yet scientists are still uncovering basic biological information including the identification of local snail and parasite species that cause SI. Previous research primarily focused on lakes in the northern half of Michigan's lower peninsula, although SI occurs throughout the state. We surveyed snails and snail-borne trematodes in lakes across Michigan's lower peninsula and used quantitative polymerase chain reaction analysis of filtered water samples to identify parasites to the species level, including a recently discovered parasite species that uses the snail Planorbella (Helisoma) trivolvis as its intermediate host. Most SI mitigation efforts have focused on a parasite species hosted by the snail Lymnaea catescopium ( = Stagnicola emarginata); however, lymnaeid snails and their associated schistosome species were largely restricted to northern lakes. In contrast, P. trivolvis and its associated parasite species were common in both northern and southern Michigan lakes. A third schistosome species associated with physid snails was also present at low levels in both northern and southern lakes. These results indicate that the recently discovered parasite species and its planorbid snail intermediate host may be more important drivers of Michigan SI than previously thought, possibly due to increased definitive host abundance in recent decades. These results have potentially important implications for SI mitigation and control efforts.

Growth and Cyclin-E Expression in the Stony Coral Species Orbicella faveolata Post-Microfragmentation.

AbstractCoral growth is critical to reef health, resilience under rapidly changing environmental conditions, and restoration efforts. Although fragmenting coral has been occurring for many years in an effort to restore reefs, recently it was discovered that microfragmenting, the process of cutting one piece of coral into many small pieces (about three to five polyps), induces exponential growth. Our study investigates the process by which microfragments of nine different genotypes from the stony coral species Orbicella faveolata grow and exhibit Cyclin-E expression. Microfragments were examined by using a high-powered dissecting microscope with a camera to document the precise areas of tissue exhibiting exponential growth. We found that new polyp formation occurs only on the microfragment edges and that edge polyp growth rates varied between different genotypes. We then extracted tissue from both the edge and the center of five genotypes for genetic analysis. We chose to analyze Cyclin-E expression because it is involved with stimulating mitotic division and is a conserved signaling pathway that is known to exist in Drosophila, mammals, and Cnidaria. Two primers for Cyclin-E were utilized to examine the level of expression for center and edge tissue. We found that Cyclin-E is expressed differentially between O. faveolata polyps, with a tendency for increased expression of the Cyclin-E in edge versus center tissue in each of five genotypes, although this result was not significant. Despite consistently higher levels of Cyclin-E expression within an organism's edge tissue, genotypes varied significantly in the degree of increased expression. This variation positively correlated with growth rate, suggesting the potential for molecular selection in aid of more rapid reef restoration. Future work will focus on deciphering the specific growth pathways involved in microfragmented coral growth and analyzing expression patterns in injured tissues.

Direct evidence for increased disease resistance in polyandrous broods exists only in eusocial Hymenoptera.

BACKGROUND: The 'genetic diversity' hypothesis posits that polyandry evolved as a mechanism to increase genetic diversity within broods. One extension of this hypothesis is the 'genetic diversity for disease resistance' hypothesis (GDDRH). Originally designed for eusocial Hymenoptera, GDDRH states that polyandry will evolve as an effect of lower parasite prevalence in genetically variable broods. However, this hypothesis has been broadly applied to several other taxa. It is unclear how much empirical evidence supports GDDRH specifically, especially outside eusocial Hymenoptera. RESULTS: This question was addressed by conducting a literature review and posteriorly conducting meta-analyses on the data available using Hedges's g. The literature review found 10 direct and 32 indirect studies with both having a strong publication bias towards Hymenoptera. Two meta-analyses were conducted and both found increased polyandry (direct tests; n = 8, g = 0.2283, p = < 0.0001) and genetic diversity generated by other mechanisms (indirect tests; n = 10, g = 0.21, p = < 0.0001) reduced parasite load. A subsequent moderator analysis revealed that there were no differences among Orders, indicating there may be applicability outside of Hymenoptera. However, due to publication bias and low sample size we must exercise caution with these results. CONCLUSION: Despite the fact that the GDDRH was developed for Hymenoptera, it is frequently applied to other taxa. This study highlights the low amount of direct evidence supporting GDDRH, particularly outside of eusocial Hymenoptera. It calls for future research to address species that have high dispersal rates and contain mixes of solitary and communal nesting.

Necrotizing Fasciitis and Toxic Shock Syndrome from Clostridium septicum following a Term Cesarean Delivery.

Necrotizing fasciitis and toxic shock syndrome are life-threatening conditions that can be seen after any surgical procedure. With only 4 previous published case reports in the obstetrics and gynecology literature of these two conditions occurring secondary to Clostridium septicum, we describe a case of necrotizing fasciitis and toxic shock syndrome occurring after a term cesarean delivery caused by this microorganism, requiring aggressive medical and surgical intervention.

Exposure to parasites increases promiscuity in a freshwater snail.

Under the Red Queen hypothesis, outcrossing can produce genetically variable progeny, which may be more resistant, on average, to locally adapted parasites. Mating with multiple partners may enhance this resistance by further increasing the genetic variation among offspring. We exposed Potamopyrgus antipodarum to the eggs of a sterilizing, trematode parasite and tested whether this altered mating behaviour. We found that exposure to parasites increased the number of snail mating pairs and the total number of different mating partners for both males and females. Thus, our results suggest that, in host populations under parasite-mediated selection, exposure to infective propagules increases the rate of mating and the number of mates.

Spermatozoa Production by Triploid Males in the New Zealand Freshwater Snail Potamopyrgus antipodarum.

Asexual lineages derived from dioecious taxa are typically assumed to be all female. Even so, asexual females from a variety of animal taxa occasionally produce males. The existence of these males sets the stage for potential gene flow across asexual lineages as well as between sexual and asexual lineages. A recent study showed that asexual triploid female Potamopyrgus antipodarum, a New Zealand freshwater snail often used as a model to study sexual reproduction, occasionally produce triploid male offspring. Here, we show that these triploid male P. antipodarum 1) have testes that produce morphologically normal sperm, 2) make larger sperm cells that contain more nuclear DNA than the sperm produced by diploid sexual males, and 3) produce sperm that range in DNA content from haploid to diploid, and are often aneuploid. Analysis of meiotic chromosomes of triploid males showed that aberrant pairing during prophase I likely accounts for the high variation in DNA content among sperm. These results indicate that triploid male P. antipodarum produce sperm, but the extent to which these sperm are able to fertilize female ova remains unclear. Our results also suggest that the general assumption of sterility in triploid males should be more closely examined in other species in which such males are occasionally produced.

Fluconazole susceptibility of vaginal isolates obtained from women with complicated Candida vaginitis: clinical implications.

Despite considerable evidence of azole resistance in oral candidiasis due to Candida species, little is known about the azole susceptibilities of the genital tract isolates responsible for vaginitis. The fluconazole susceptibilities of vaginal isolates obtained during a multicenter study of 556 women with complicated Candida vaginitis were determined by evaluating two fluconazole treatment regimens. Of 393 baseline isolates of Candida albicans, 377 (96%) were highly susceptible to fluconazole (MICs, <8 microg/ml) and 14 (3.6%) were resistant (MICs, >or=64 microg/ml). Following fluconazole therapy, one case of in vitro resistance developed during 6 weeks of monitoring. In accordance with the NCCLS definition, in vitro fluconazole resistance correlated poorly with the clinical response, although a trend of a higher mycological failure rate was found (41 versus 19.6% on day 14). By using an alternative breakpoint of 1 micro g/ml, based upon the concentrations of fluconazole achievable in vaginal tissue, no significant differences in the clinical and mycological responses were observed when isolates (n = 250) for which MICs were 1 microg/ml, although a trend toward an improved clinical outcome was noted on day 14 (odds ratio, >2.7; 95% confidence interval, 0.91, 8.30). Although clinical failure was uncommon, symptomatic recurrence or mycological relapse almost invariably occurred with highly sensitive strains (MICs, <1.0 microg/ml). In vitro fluconazole resistance developed in 2 of 18 initially susceptible C. glabrata isolates following fluconazole exposure. Susceptibility testing for women with complicated Candida vaginitis appears to be unjustified.

Synthesis and biological evaluation of prostaglandin-F alkylphosphinic acid derivatives as bone anabolic agents for the treatment of osteoporosis.

A series of novel C(1) alkylphosphinic acid analogues of the prostaglandin-F family have been evaluated at the eight human prostaglandin receptors for potential use in the treatment of osteoporosis. Using molecular modeling as a tool for structure-based drug design, we have discovered that the phosphinic acid moiety (P(O)(OH)R) behaves as an isostere for the C(1) carboxylic acid in the human prostaglandin FP binding assay in vitro and possesses enhanced hFP receptor selectivity when compared to the parent carboxylic acid. When evaluated in vivo, the methyl phosphinic acid analogue (4b) produced a bone anabolic response in rats, returning bone mineral volume (BMV) [corrected], to intact levels in the distal femur in the ovariectomized rat (OVX) model. These results suggest that prostaglandins of this class may be useful agents in the treatment of diseases associated with bone loss.

Effectiveness of a rescue dose of antenatal betamethasone after an initial single course.

OBJECTIVE: To evaluate the effects of a single rescue dose of antenatal betamethasone after an initial single course on the frequency of neonatal respiratory distress syndrome and perinatal infectious morbidity in pregnancies complicated with preterm labor and delivery. STUDY DESIGN: We performed a cohort analysis of singleton pregnancies for which delivery occurred between 28 and 34 weeks' gestation after a single course of betamethasone administered before 28 weeks' gestation. Patients were then segregated into the following 2 groups on the basis of betamethasone exposure at the delivery admission: (1) a single 12-mg injection (rescue group) and (2) observation only (observation group). Patients who delivered infants within 24 hours of the rescue dose were excluded, as were those who had ruptured membranes for longer than 24 hours before delivery, those with diabetes that required insulin, and those with exposure to repeated doses of betamethasone before admission. Data were analyzed by use of the Student t test, chi2 test, and Fisher exact test. Multiple logistic regression was performed to examine the effect of each steroid dosing regimen on respiratory distress syndrome. Two-tailed P values <.05 were considered to be significant. RESULTS: A total of 152 patients were included, with 89 in the rescue group and 63 in the observation group. Both groups were similar with respect to maternal demographics, mean gestational age at the initial single course and at delivery, mode of delivery, and mean birth weights. Rescue administration was significantly associated with a reduction in the frequency of respiratory distress syndrome (odds ratio, 0.44; 95% confidence interval, 0.2 to 0.9) and mean ventilator days (odds ratio, 0.44; 95% confidence interval, 0.2 to 0.8) compared with observation alone. All other studied perinatal outcomes analyzed were similar between the groups. Multiple logistic regression confirmed an independent association between a single rescue dose and a reduction in the frequency of respiratory distress syndrome (odds ratio, 0.40; 95% confidence interval, 0.2 to 0.9). CONCLUSIONS: A single rescue dose of betamethasone is associated with a reduction in the frequency of respiratory distress syndrome without an apparent increase in perinatal infectious disease.

Scheduled cesarean delivery and the prevention of human immunodeficiency virus transmission: a survey of practicing obstetricians.

OBJECTIVE: To characterize practice patterns among obstetrician-gynecologists with respect to delivery for human immunodeficiency virus (HIV)-seropositive women, following publication of the 1999 American College of Obstetricians and Gynecologists (ACOG) Committee Opinion regarding scheduled cesarean delivery for HIV-infected patients. METHODS: A 25-question, multiple-choice survey was mailed to 2000 randomly selected obstetrician-gynecologists: 1000 maternal-fetal medicine specialists and 1000 general obstetrician-gynecologists. Mailing addresses were obtained from the 1999-2000 editions of the Society for Maternal-Fetal Medicine (SMFM) and ACOG membership directories. Information was requested about general perceptions of the 1999 ACOG Committee Opinion and about practice patterns with respect to management of HIV disease in pregnancy. Data were analyzed by using descriptive statistics and the chi-square test. Any P values <.05 were considered significant. RESULTS: After a single mailing we received 512 responses (25.6%), including 433 (43%) from SMFM members and 79 (8%) from ACOG members. Among the respondents, 47% disagreed with the current scientific validity of the 1999 ACOG Committee Opinion recommendation to offer cesarean delivery to all HIV-seropositive pregnant women. No statistically significant differences were detected in the demographic profiles, years of experience, or practice settings of participants who agreed with the scientific validity when compared to those who did not. Most respondents used viral load detection (87%) monitored on a trimester basis (67%) for clinical management decisions. Most practitioners (72%) do not recommend cesarean delivery for women who are compliant with antiretroviral therapy and who have undetectable viral loads regardless of CD4 counts. However, most practitioners (67%) do recommend cesarean delivery for those compliant women with detectable viral loads, irrespective of CD4 counts (67%). CONCLUSIONS: There is considerable disagreement among practicing obstetricians with respect to the 1999 ACOG Committee Opinion recommendation to offer cesarean delivery to all HIV-seropositive women. Most physicians use viral load detection to assist with the counseling in delivery options for HIV-infected pregnant women.

Treatment of complicated Candida vaginitis: comparison of single and sequential doses of fluconazole.

OBJECTIVE: An attempt was made to validate recent recommendations that women with complicated Candida vaginitis (severe or recurrent, non-albicans Candida spp or abnormal host) require longer-duration antifungal therapy to achieve clinical cure and mycologic eradication. STUDY DESIGN: A prospective, multicenter, randomized, double-blind study was performed comparing a single dose of 150 mg of fluconazole with 2 sequential 150-mg doses of fluconazole given 3 days apart. RESULTS: Five hundred fifty-six women with severe or recurrent Candida vaginitis were enrolled, and 398 had at least one postbaseline evaluation (intent to treat) and of these 309 were fully evaluable (efficacy-valid). At baseline, 92% of vaginal isolates were Candida albicans. The 2-dose fluconazole regimen achieved significantly higher clinical cure rates in women with severe vaginitis when evaluated on day 14 (P =.015) and higher clinical and mycologic responses persisted at day 35. Women with recurrent but not severe vaginitis did not benefit clinically short term by the additional fluconazole dose. Multivariate logistic regression analysis showed that being infected with non-albicans Candida predicted significantly reduced clinical and mycologic response regardless of duration of therapy. Fluconazole therapy was well tolerated and free of serious adverse effects. CONCLUSION: Treatment of Candida vaginitis requires individualization, and women with severe Candida vaginitis achieve superior clinical and mycologic eradication with a 2-dose fluconazole regimen.

Hormonal and barrier contraception and risk of upper genital tract disease in the PID Evaluation and Clinical Health (PEACH) study.

OBJECTIVE: Among women diagnosed with pelvic inflammatory disease, we examined the associations between hormonal or barrier methods of contraception and upper genital tract infection or inflammation. METHODS: Participants were 563 patients from a treatment trial for pelvic inflammatory disease. All had pelvic pain; pelvic organ tenderness; and leukorrhea, mucopurulent cervicitis, or untreated cervicitis. Contraceptive use within the prior 4 weeks was compared among women with baseline upper genital tract gonorrhea or chlamydia, women with endometritis without upper genital tract gonorrhea or chlamydia, and women with neither upper genital tract gonorrhea or chlamydia nor endometritis. RESULTS: Inconsistent condom use was significantly and independently associated with a 2 to 3 times elevated risk for upper genital tract infection. Upper genital tract gonorrhea or chlamydia was not significantly associated with use of oral contraceptives, use of medroxyprogesterone, condoms used consistently, nor other barrier methods. CONCLUSION: No hormonal or barrier contraceptive method was related to a reduction in upper genital tract disease among women with clinical pelvic inflammatory diseases.

Antibiotic resistance patterns of group B streptococci in late third-trimester rectovaginal cultures.

OBJECTIVE: Our purpose was to determine the antibiotic sensitivity patterns of rectovaginal group B streptococcal isolates obtained from a heterogeneous obstetric population in the late third trimester. STUDY DESIGN: We performed a prospective observational study of rectovaginal group B streptococcal isolates obtained in the late third trimester during routine screening over a 12-month period. All cultures were prepared in a selective broth medium for 18 to 24 hours before plating onto sheep blood agar. Susceptibility testing of all isolates was performed for ampicillin, cefazolin, clindamycin, erythromycin, penicillin G, and vancomycin with the E-test method. RESULTS: A total of 2111 consecutive rectovaginal cultures were performed in which group B streptococci were isolated from 574 (27.2%) different patients. The "antibiogram" of the susceptible percentage is as follows: vancomycin, 100%; ampicillin, 98.2%; penicillin G, 98.2%; cefazolin, 98.1%; clindamycin, 92%; erythromycin, 81%. Ten isolates (1.8%) demonstrated intermediate susceptibility to both ampicillin and penicillin G. CONCLUSION: Routine susceptibility testing of group B streptococcal isolates collected during pregnancy should be considered because of the emergence of antibiotic resistance among group B streptococcal strains.

Douching and endometritis: results from the PID evaluation and clinical health (PEACH) study.

BACKGROUND: Douching has been related to risk of pelvic inflammatory disease (PID). GOAL: To examine the association between douching and PID in a large, multicenter, clinical trial of PID after adjustment for race/ethnicity. STUDY DESIGN: Interviews were conducted with 654 women who had signs and symptoms of PID. Vaginal Gram stains and upper genital tract pathology/cultures were obtained from all the women. Women with evidence of plasma cell endometritis and/or gonococcal or chlamydial upper genital tract infections were compared with women who had neither endometritis nor upper genital tract infection. RESULTS: Women with endometritis or upper genital tract infection were more likely to have douched more than once a month or within 6 days of enrollment than women who never douched. These associations remained after adjustment for confounding factors, after analysis of black women only; and among women with normal or intermediate vaginal flora but not bacterial vaginosis. CONCLUSION: Among a predominantly black group of women with clinical PID, frequent and recent douching was associated with endometritis and upper genital tract infection.

Clinical predictors of endometritis in women with symptoms and signs of pelvic inflammatory disease.

OBJECTIVE: Careful detection and treatment of pelvic inflammatory disease are essential for the prevention of adverse sequelae. The purpose of this study was to evaluate the diagnostic test characteristics of clinical criteria for the diagnosis of pelvic inflammatory disease. STUDY DESIGN: We performed a cross-sectional analysis of the baseline characteristics of 651 patients enrolled in a multicenter randomized treatment trial for pelvic inflammatory disease. Clinical and laboratory findings were recorded for all patients, and endometrial sampling was performed. We calculated sensitivity and specificity and performed receiver operating characteristic curve analysis and multivariate logistic regression, using histologic endometritis as the criterion standard. RESULTS: The minimal criteria for pelvic inflammatory disease, as recommended by the Centers for Disease Control and Prevention, had a sensitivity of 83%, in comparison with a 95% sensitivity for adnexal tenderness (P =.001). Of the supportive clinical criteria, the finding most highly associated with endometritis was a positive test result for Chlamydia trachomatis or Neisseria gonorrhoeae (adjusted odds ratio, 4.3; 95% confidence interval, 2.89--6.63). A multivariate logistic regression model indicated that combinations of criteria significantly improve the prediction of endometritis. CONCLUSION: Sensitivity can be maximized by using the presence of adnexal tenderness as a minimal criterion for the diagnosis of pelvic inflammatory disease, and supportive criteria are helpful in estimating the probability of endometritis.

An efficient synthesis of 3-hetero-13,14-dihydro prostaglandin F1alpha analogues.

[structure: see text]. A new class of 3-hetero-13,14-dihydro prostaglandin F(1)(alpha) analogues was synthesized from a common intermediate. The latter was constructed via a two-step, three-component process. The lower chain, containing the 15-(phenoxymethyl) group, was synthesized in enantiopure form using Jacobsen's (salen)Co-catalyzed kinetic resolution of a terminal epoxide with phenol.

Is betamethasone effective longer than 7 days after treatment?

OBJECTIVE: To determine whether perinatal outcomes are influenced by the interval between antenatal betamethasone administration and delivery. METHODS: We did a retrospective cohort analysis of live-born singleton neonates born between 28 and 34 weeks' gestation after a single course of betamethasone, defined as two 12-mg doses over 24 hours. Subjects were grouped according to length of interval between initial betamethasone dose and delivery (1-2 days, 3-7 days, and 8-14 days). We excluded women who had membranes ruptured for longer than 24 hours before delivery, delivery before the second dose of betamethasone, or more than two doses of betamethasone. Data were analyzed by Student t test, chi(2) test, or Fisher exact test. Multiple logistic regression analyses were done using suspected risk factors for respiratory distress syndrome (RDS) and intraventricular hemorrhage (IVH). We calculated that a sample of 200 women would provide more than 80% power to detect a 50% reduction in incidence of RDS for a two-sided test of significance at a critical level of.05. RESULTS: Among 216 women, 97 delivered in 1-2 days, 78 in 3-7 days, and 41 in 8-14 days after a single course of betamethasone. Groups were similar in selected demographics, tocolytic exposure, gestational age at delivery, modes of delivery, and mean birth weights. There were no significant differences in frequencies of RDS (39.2%, 41.1%, and 36.6%, respectively) or grades 3-4 IVH (1.1%, 1.3%, and 0%, respectively) between groups. Frequencies of selected perinatal infectious outcomes also were similar between groups. Multiple logistic regression analyses found no association between RDS or IVH and delivery more than 7 days from betamethasone therapy. CONCLUSION: There were no differences in perinatal outcomes in pregnancies delivered 8-14 days after antenatal exposure to betamethasone compared with those delivered within 7 days of exposure.

Urinalysis and urinary tract infection: update for clinicians.

Dysuria is a common presenting complaint of women and urinalysis is a valuable tool in the initial evaluation of this presentation. Clinicians need to be aware that pyuria is the best determinate of bacteriuria requiring therapy and that values significant for infection differ depending on the method of analysis. A hemocytometer yields a value of > or = 10 WBC/mm3 significant for bacteriuria, while manual microscopy studies show > or = 8 WBC/high-power field reliably predicts a positive urine culture. In cases of uncomplicated symptomatic urinary tract infection, a positive value for nitrites and leukocyte esterase by urine dipstick can be treated without the need for a urine culture. Automated urinalysis used widely in large volume laboratories provides more sensitive detection of leukocytes and bacteria in the urine. With automated microscopy, a value of > 2 WBC/hpf is significant pyuria indicative of inflammation of the urinary tract. In complicated cases such as pregnancy, recurrent infection or renal involvement, further evaluation is necessary including manual microscopy and urine culture with sensitivities.

Neonatal sepsis and death after multiple courses of antenatal betamethasone therapy.

OBJECTIVE: This study was undertaken to compare the effects of single versus multiple courses of betamethasone therapy on the frequencies of neonatal outcomes and perinatal infectious morbidity among singleton pregnancies complicated by preterm delivery. STUDY DESIGN: We performed a nonconcurrent prospective analysis of singleton pregnancies delivered between 24 and 34 weeks' gestation after antenatal betamethasone exposure. Patients were categorized into two groups according to betamethasone exposure: (1) two 12-mg doses in a 24-hour interval on admission (single-course group) and (2) repeated dosing after the initial single course (multiple-course group). All patients received prophylactic antibiotics for group B streptococci. Any patients with ruptured membranes for >24 hours before delivery were excluded. Data were analyzed with the Student t test, the chi(2) test, and the Fisher exact test. Multiple logistic regression analyses were performed to examine the effect of each steroid dosing regimen on early-onset neonatal sepsis and neonatal death. P <.05 was considered significant for all 2-tailed tests. RESULTS: A total of 453 patients were included, with 267 in the single-course group and 186 in the multiple-course group. The two groups were similar with respect to maternal demographic characteristics, gestational age at delivery, mode of delivery, birth weight, and maternal group B streptococcal colonization. Multiple courses were significantly associated with early-onset neonatal sepsis (odds ratio, 5.00; 95% confidence interval, 1.3-23. 2), chorioamnionitis (odds ratio, 9.96; 95% confidence interval, 2. 1-64.6), endometritis (odds ratio, 3.61; 95% confidence interval, 1. 7-8.1), and neonatal death (odds ratio, 2.92; 95% confidence interval, 1.3-6.9). The frequencies of the other neonatal outcomes analyzed, including respiratory distress syndrome and grade III or IV intraventricular hemorrhage, were similar between the 2 groups. Multiple logistic regression analyses confirmed that multiple courses of antenatal betamethasone were independently associated with early-onset neonatal sepsis (odds ratio, 1.25; 95% confidence interval, 1.1-1.9) and neonatal death (odds ratio, 1.70; 95% confidence interval, 1.1-1.9). CONCLUSIONS: Multiple courses of antenatal betamethasone are associated with increased risks of perinatal infectious morbidity and neonatal death.

Effectiveness of antenatal corticosteroid administration after preterm premature rupture of the membranes.

OBJECTIVE: This study was undertaken to determine the effect of antenatal betamethasone administration on the incidences of respiratory distress syndrome, intraventricular hemorrhage, and perinatal infectious morbidity in the setting of preterm premature rupture of membranes. STUDY DESIGN: We performed a nonconcurrent prospective analysis of women with singleton pregnancies who were delivered between 24 and 32 weeks' gestation after preterm premature rupture of membranes. Patients were subdivided into 2 groups according to betamethasone exposure: (1) none (control group) and (2) two 12-mg doses in a 24-hour interval on admission (single-course group). Patients who received >2 doses of betamethasone were excluded. All patients received broad-spectrum prophylactic antibiotics. Data were analyzed with the Student t test, the chi(2) test, and the Fisher exact test. Multiple logistic regression analyses incorporated multiple variables considered risk factors for respiratory distress syndrome and intraventricular hemorrhage. P <.05 for all 2-tailed tests was considered significant. RESULTS: A total of 362 patients were included, with 203 in the control group and 159 in the single-course group. Patients in these groups were delivered at 31.0 +/- 3.0 and 30.2 +/- 2.7 (mean +/- SD) weeks' gestation, respectively. The groups were similar with respect to selected demographic characteristics, latency until delivery, mode of delivery, birth weight, and maternal group B streptococcal colonization status. Univariate analysis demonstrated significant decreases in the frequencies of both respiratory distress syndrome (odds ratio, 0.31; 95% confidence interval, 0.2-0.5) and grade III/IV intraventricular hemorrhage (odds ratio, 0.14; 95% confidence interval, 0.1-0.6) in the single-course group. The frequencies of early neonatal sepsis, chorioamnionitis, endometritis, and neonatal death were similar between groups. Multiple logistic regression analyses determined that a single course of betamethasone was independently associated with reductions in the frequencies of both respiratory distress syndrome (odds ratio, 0.16; 95% confidence interval, 0.1-0.4) and grade III/IV intraventricular hemorrhage (odds ratio, 0.18; 95% confidence interval, 0.1-0.4). CONCLUSIONS: A single course of betamethasone administered antenatally to patients with preterm premature rupture of membranes was associated with decreases in the frequencies of both respiratory distress syndrome and advanced grades of intraventricular hemorrhage without any increase in perinatal infectious morbidity.