Clinical interventions to reduce stillbirths in sub-Saharan Africa: a mathematical model to estimate the potential reduction of stillbirths associated with specific obstetric conditions.

OBJECTIVE: Stillbirths are among the most common adverse pregnancy outcomes, with 98% occurring in low-income countries. More than one-third occur in sub-Saharan Africa (SSA). However, the medical conditions causing stillbirths and interventions to reduce stillbirths from these conditions are not well documented. We estimated the reductions in stillbirths possible with combinations of interventions. DESIGN: We developed a computerised model to estimate the impact of various interventions on stillbirths caused by the most common conditions. The model considered the location of obstetric care (home, clinic or hospital) and each intervention's efficacy, penetration and utilisation. Maternal transfers were also considered. SETTING AND POPULATION: Pregnancies in SSA in 2012. METHODS: For each condition, we created a series of scenarios involving different combinations of interventions and modelled their impact on stillbirth rates. MAIN OUTCOME MEASURES: Stillbirths associated with various maternal and fetal conditions and the percentage reduction with various interventions. RESULTS: Eight to ten maternal and fetal conditions were responsible for most stillbirths, but none for more than 15%. The most common conditions causing stillbirths in SSA include obstructed labour and uterine rupture, fetal distress and umbilical cord complications, fetal growth restriction, pre-eclampsia/eclampsia, and placental abruption/placenta praevia. Syphilis and malaria contribute smaller numbers. Reducing stillbirths requires appropriate diagnosis and management of each condition, usually including hospital care for monitoring and delivery, often by caesarean section. Maternal syphilis and malaria were the only conditions for which outpatient management alone reduced stillbirth. CONCLUSIONS: Most stillbirths in low-income countries occur at term and during labour and therefore are preventable by appropriate obstetric care. Management focused on the maternal and fetal conditions that cause stillbirths is necessary to achieve stillbirth rates approaching those found in high-income countries. TWEETABLE ABSTRACT: Reducing stillbirth incidence requires appropriate management of each causative condition and often caesarean delivery.

Cervical funneling or intra-amniotic debris and preterm birth in nulliparous women with midtrimester cervical length less than 30 mm.

OBJECTIVE: To evaluate whether the presence of cervical funneling or intra-amniotic debris identified in the second trimester is associated with a higher rate of preterm birth (PTB) in asymptomatic nulliparous pregnant women with a midtrimester cervical length (CL) less than 30 mm (i.e. below the 10th percentile). METHODS: This was a secondary cohort analysis of data from a multicenter trial in nulliparous women between 16 and 22 weeks' gestation with a singleton gestation and CL less than 30 mm on transvaginal ultrasound, randomized to treatment with either 17-alpha-hydroxyprogesterone caproate or placebo. Sonographers were centrally certified in CL measurement, as well as in identification of intra-amniotic debris and cervical funneling. Univariable and multivariable analysis was performed to assess the associations of cervical funneling and intra-amniotic debris with PTB. RESULTS: Of the 657 women randomized, 112 (17%) had cervical funneling only, 33 (5%) had intra-amniotic debris only and 45 (7%) had both on second-trimester ultrasound. Women with either of these findings had a shorter median CL than those without (21.0 mm vs 26.4 mm; P < 0.001). PTB prior to 37 weeks was more likely in women with cervical funneling (37% vs 21%; odds ratio (OR), 2.2 (95% CI, 1.5-3.3)) or intra-amniotic debris (35% vs 23%; OR, 1.7 (95% CI, 1.1-2.9)). Results were similar for PTB before 34 and before 32 weeks' gestation. After multivariable adjustment that included CL, PTB < 34 and < 32 weeks continued to be associated with the presence of intra-amniotic debris (adjusted OR (aOR), 1.85 (95% CI, 1.00-3.44) and aOR, 2.78 (95% CI, 1.42-5.45), respectively), but not cervical funneling (aOR, 1.17 (95% CI, 0.63-2.17) and aOR, 1.45 (95% CI, 0.71-2.96), respectively). CONCLUSIONS: Among asymptomatic nulliparous women with midtrimester CL less than 30 mm, the presence of intra-amniotic debris, but not cervical funneling, is associated with an increased risk for PTB before 34 and 32 weeks' gestation, independently of CL. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Neonatal Genetic Variation in Steroid Metabolism and Key Respiratory Function Genes and Perinatal Outcomes in Single and Multiple Courses of Corticosteroids.

OBJECTIVE: The aim of the study is to evaluate the association of steroid metabolism and respiratory gene polymorphisms in neonates exposed to antenatal corticosteroids (ACS) with respiratory outcomes, small for gestational age (SGA), and response to repeat ACS. STUDY DESIGN: This candidate gene study is a secondary analysis of women enrolled in a randomized controlled trial of single versus weekly courses of ACS. Nineteen single nucleotide polymorphisms (SNPs) in 13 steroid metabolism and respiratory function genes were evaluated. DNA was extracted from placenta or fetal cord serum and analyzed with TaqMan genotyping. Each SNP was evaluated for association via logistic regression with respiratory distress syndrome (RDS), continuous positive airway pressure (CPAP)/ventilator use (CPV), and SGA. RESULTS: CRHBP, CRH, and CRHR1 minor alleles were associated with an increased risk of SGA. HSD11B1 and SCNN1B minor alleles were associated with an increased likelihood of RDS. Carriage of minor alleles in SerpinA6 was associated with an increased risk of CPV. CRH and CRHR1 minor alleles were associated with a decreased likelihood of CPV. CONCLUSION: Steroid metabolism and respiratory gene SNPs are associated with respiratory outcomes and SGA in patients exposed to ACS. Risks for respiratory outcomes are affected by minor allele carriage as well as by treatment with multiple ACS.

The association of beta-2 adrenoceptor genotype with short-cervix mediated preterm birth: a case-control study.

OBJECTIVE: To determine whether ß2 -adrenoceptor (ß2 AR) genotype is associated with shortening of the cervix or with preterm birth (PTB) risk among women with a short cervix in the second trimester. DESIGN: A case-control ancillary study to a multicentre randomised controlled trial. SETTING: Fourteen participating centres of the Maternal-Fetal Medicine Units Network of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. POPULATION: Four hundred thirty-nine women, including 315 with short cervix and 124 with normal cervical length. METHODS: Nulliparous women with cervical length <30 mm upon a 16-22-week transvaginal sonogram and controls frequency-matched for race/ethnicity with cervical lengths ≥40 mm were studied. ß2 AR genotype was determined at positions encoding for amino acid residues 16 and 27. MAIN OUTCOME MEASURES: Genotype distributions were compared between case and control groups. Within the short cervix group, pregnancy outcomes were compared by genotype, with a primary outcome of PTB <37 weeks. RESULTS: Genotype data were available at position 16 for 433 women and at position 27 for 437. Using a recessive model testing for association between short cervix and genotype, and adjusted for ethnicity, there was no statistical difference between cases and controls for Arg16 homozygosity (OR 0.7, 95% CI 0.4-1.3) or Gln27 homozygosity (OR 0.9, 95% CI 0.3-2.7). Among cases, Arg16 homozygosity was not associated with protection from PTB or spontaneous PTB. Gln27 homozygosity was not associated with PTB risk, although sample size was limited. CONCLUSIONS: ß2 AR genotype does not seem to be associated with short cervical length or with PTB following the second-trimester identification of a short cervix. Influences on PTB associated with ß2 AR genotype do not appear to involve a short cervix pathway.

Effectiveness of progestogens to improve perinatal outcome in twin pregnancies: an individual participant data meta-analysis.

BACKGROUND: In twin pregnancies, the rates of adverse perinatal outcome and subsequent long-term morbidity are substantial, and mainly result from preterm birth (PTB). OBJECTIVES: To assess the effectiveness of progestogen treatment in the prevention of neonatal morbidity or PTB in twin pregnancies using individual participant data meta-analysis (IPDMA). SEARCH STRATEGY: We searched international scientific databases, trial registration websites, and references of identified articles. SELECTION CRITERIA: Randomised clinical trials (RCTs) of 17-hydroxyprogesterone caproate (17Pc) or vaginally administered natural progesterone, compared with placebo or no treatment. DATA COLLECTION AND ANALYSIS: Investigators of identified RCTs were asked to share their IPD. The primary outcome was a composite of perinatal mortality and severe neonatal morbidity. Prespecified subgroup analyses were performed for chorionicity, cervical length, and prior spontaneous PTB. MAIN RESULTS: Thirteen trials included 3768 women and their 7536 babies. Neither 17Pc nor vaginal progesterone reduced the incidence of adverse perinatal outcome (17Pc relative risk, RR 1.1; 95% confidence interval, 95% CI 0.97-1.4, vaginal progesterone RR 0.97; 95% CI 0.77-1.2). In a subgroup of women with a cervical length of ≤25 mm, vaginal progesterone reduced adverse perinatal outcome when cervical length was measured at randomisation (15/56 versus 22/60; RR 0.57; 95% CI 0.47-0.70) or before 24 weeks of gestation (14/52 versus 21/56; RR 0.56; 95% CI 0.42-0.75). AUTHOR'S CONCLUSIONS: In unselected women with an uncomplicated twin gestation, treatment with progestogens (intramuscular 17Pc or vaginal natural progesterone) does not improve perinatal outcome. Vaginal progesterone may be effective in the reduction of adverse perinatal outcome in women with a cervical length of ≤25 mm; however, further research is warranted to confirm this finding.

Gut hormone activity of children born to women with and without gestational diabetes.

UNLABELLED: What is already known about this subject Children born to women with gestational diabetes have greater risk for obesity. Obesity in adults and children is associated with blunted postprandial gut hormone responses. What this study adds Children of women with gestational diabetes have a blunted postprandial response of GLP-1. Children of women with gestational diabetes have high fasting PYY concentrations. BACKGROUND: Intrauterine exposure to gestational diabetes mellitus (GDM) increases risk for obesity. Obesity is associated with a blunted postprandial gut hormone response, which may impair satiety and thereby contribute to weight gain. The postprandial response of gut hormones among children of women with GDM has not previously been investigated. OBJECTIVE: To examine whether children of women with GDM have suppressed peptide-tyrosine-tyrosine (PYY) and glucagon-like-peptide-1 (GLP-1), and higher concentrations of ghrelin, following a meal challenge. A secondary objective was to investigate associations of these hormones with children's free-living energy intake. METHODS: Children (n = 42) aged 5-10 years were stratified into two groups: offspring of GDM mothers (OGD) and of non-diabetic mothers (CTRL). Body composition was measured by dual-energy X-ray absorptiometry, and circulating PYY, GLP-1 and total ghrelin were measured during a liquid meal challenge. Energy intake was assessed by three 24-h diet recalls. RESULTS: Between-groups analyses of fasting and incremental area under the curve (AUC) found no differences in ghrelin. Incremental AUC for GLP-1 was greater among the CTRL vs. OGD (P < 0.05), and fasting PYY, but not incremental AUC, was higher among OGD vs. CTRL (P < 0.01). Associations of fasting and incremental AUC for each gut hormone with children's usual energy intake did not differ significantly by group. CONCLUSIONS: Further research is needed to more fully examine the potential role of postprandial GLP-1 suppression and high-fasting PYY concentrations on the feeding behaviour and risk for obesity among children exposed to GDM in utero.

Vitamin D status and recurrent preterm birth: a nested case-control study in high-risk women.

OBJECTIVE: To determine whether vitamin D status is associated with recurrent preterm birth, and any interactions between vitamin D levels and fish consumption. DESIGN: A nested case-control study, using data from a randomised trial of omega-3 fatty acid supplementation to prevent recurrent preterm birth. SETTING: Fourteen academic health centres in the USA. POPULATION: Women with prior spontaneous preterm birth. METHODS: In 131 cases (preterm delivery at <35 weeks of gestation) and 134 term controls, we measured serum 25-hydroxyvitamin D [25(OH)D] concentrations by liquid chromatography-tandem mass spectrometry (LC-MS) from samples collected at baseline (16-22 weeks of gestation). Logistic regression models controlled for study centre, maternal age, race/ethnicity, number of prior preterm deliveries, smoking status, body mass index, and treatment. MAIN OUTCOME MEASURES: Recurrent preterm birth at <37 and <32 weeks of gestation. RESULTS: The median mid-gestation serum 25(OH)D concentration was 67 nmol/l, and 27% had concentrations of <50 nmol/l. Serum 25(OH)D concentration was not significantly associated with preterm birth (OR 1.33; 95% CI 0.48-3.70 for lowest versus highest quartiles). Likewise, comparing women with 25(OH)D concentrations of 50 nmol/l, or higher, with those with <50 nmol/l generated an odds ratio of 0.80 (95% CI 0.38-1.69). Contrary to our expectation, a negative correlation was observed between fish consumption and serum 25(OH)D concentration (-0.18, P < 0.01). CONCLUSIONS: In a cohort of women with a prior preterm birth, vitamin D status at mid-pregnancy was not associated with recurrent preterm birth.

Overweight status and intrauterine exposure to gestational diabetes are associated with children's metabolic health.

BACKGROUND: Offspring of women with gestational diabetes (OGD) have greater risk for obesity and impaired metabolic health. Whether impaired metabolic health occurs in the absence of obesity is not clear. OBJECTIVE: The purpose of this study was to investigate the independent and interactive effects of intrauterine exposure to gestational diabetes and of children's current weight status on their metabolic health. METHODS: Children aged 5­10 years (n = 51) with and without intrauterine exposure to gestational diabetes (OGD vs. offspring of non-diabetic women [CTRL]) were grouped into normal weight (body mass index [BMI] < 85th %) and overweight (BMI > 85th %) according to Centers for Disease Control growth curves. Lipid profile was obtained by fasting blood draw, insulin sensitivity (SI) and secretion by liquid meal tolerance test, and body composition by dual-energy X-ray absorptiometry. RESULTS: Despite similar average BMI percentiles among normal weight OGD versus CTRL, and overweight OGD vs. CTRL, OGD had greater total %fat and trunk fat adjusted for leg fat compared with CTRL (P < 0.05). Overweight children had lower SI (P < 0.05) and greater basal, static, and total insulin secretion independent of SI (P < 0.05). OGD was independently associated with greater static insulin secretion (P < 0.05) and the interaction between OGD and overweight was associated with greater basal insulin secretion independent of SI (P < 0.01). OGD and overweight were each associated with lower high-density lipoprotein-cholesterol (HDL-C) (P < 0.05). CONCLUSION: Intrauterine exposure to gestational diabetes was associated with greater central adiposity and insulin secretion, and lower HDL-C, irrespective of current weight status. Future research should examine respective contributions of the intrauterine environment and of underlying genotype on children's metabolic health.

Chlorhexidine vaginal and neonatal wipes in home births in Pakistan: a randomized controlled trial.

OBJECTIVE: To assess tolerance and safety of 0.6% chlorhexidine vaginal and neonatal wipes to improve perinatal outcomes in home deliveries in Pakistan and the ability of traditional birth attendants and project staff to perform a randomized trial of this intervention. METHODS: Focus groups of pregnant and nonpregnant women and in-depth interviews of traditional birth attendants explored barriers to the use of chlorhexidine wipes. Then, a study was performed of women delivering at home attended by traditional birth attendants. Consenting women were randomly assigned to receive either 0.6% chlorhexidine or saline vaginal and neonatal wipes. Women and their infants were followed up on postpartum days 7, 14, and 28. Acceptability and tolerance of vaginal and neonatal wipes, as well as maternal and neonatal outcomes, were assessed. RESULTS: The focus groups and interviews indicated that the chlorhexidine intervention would be acceptable to women and their providers. Of the 213 eligible pregnant women approached, 203 (95%) gave informed consent and were enrolled and allocated to groups. Traditional birth attendants had no difficulty administering chlorhexidine vaginal and neonatal wipes in a home setting. Of the 203 births, 103 (51%) of whom received 0.6% chlorhexidine, there were no allergic reactions, vaginal itching, burning, or requests for study termination. Follow-up at 28 days postpartum was more than 95%. Although this study was not powered to show significant differences in neonatal outcomes between treatment groups, the lower rates of some neonatal adverse clinical outcomes in the chlorhexidine group were encouraging. CONCLUSION: Use of 0.6% chlorhexidine vaginal and neonatal wipes for the prevention of neonatal infection is well-tolerated and seems safe. A trial of this intervention by traditional birth attendants in a home-delivery setting is feasible. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00121394 LEVEL OF EVIDENCE: I.

Intrapartum chlorhexidine vaginal irrigation and chorioamnion and placental microbial colonization.

OBJECTIVES: To determine whether intrapartum chlorhexidine vaginal irrigation reduces microbial colonization of the chorioamnion or placenta. METHODS: Secondary analysis was made of a randomized trial. Cultures for aerobic and anaerobic bacteria, Mycoplasma species and Ureaplasma urealyticum were performed using standard isolation techniques. RESULTS: The placentas of 83 trial participants allocated to chlorhexidine and 93 allocated to placebo underwent evaluation. These two groups were statistically balanced for risk factors for infection. Aerobic bacteria were isolated from 47% of the chlorhexidine placentas vs. 51% of the placebo placentas (relative risk 0.9, 95% confidence interval 0.7-1.3), anaerobic bacteria from 30% and 35%, respectively (0.8, 0.5-1.3), group B streptococcus from 12% and 15% (0.8, 0.4-1.7), U. urealyticum from 18% and 29% (0.6, 0.4-1.1), Mycoplasma species from 6% and 11% (0.6, 0.2-1.6), and any organism from 57% and 67%, respectively (0.8, 0.7-1.1). CONCLUSIONS: Intrapartum chlorhexidine vaginal irrigation was associated with non-significant reductions in the rates of placental microbial isolation.

The effect of the increasing prevalence of maternal obesity on perinatal morbidity.

OBJECTIVE: In this study, we assessed the temporal trends and relative and attributable perinatal risks of maternal obesity over a 20-year period. STUDY DESIGN: We conducted a retrospective cohort study between 1980 and 1999 by using a computerized perinatal database of all women who received prenatal care and delivered their infants within a regional health care system. The main outcome measures were as follows: (1) annual mean body weight and the percentage of women classified as obese at the first prenatal visit (primary definition > or = 200 lb; secondary definitions > or = 250 lb, > or = 300 lb, body mass index > 29 kg/m(2)); and (2) relative and attributable risks of obesity for selected maternal and perinatal morbidities in successive 5-year periods. RESULTS: From 1980 to 1999, the mean maternal weight of women at the first prenatal visit increased 20% (144-172 lb), as did the percentage of women > or = 200 lb (7.3-24.4), the percentage > or = 250 lb (1.9-10.7), the percentage > or = 300 lb (0.5-4.9), and the percentage with a body mass index > 29 kg/m(2) (16.3-36.4), P < .01 for all. Controlling for maternal age, race, and smoking status, obese women were at increased risk at each period for cesarean delivery (range of adjusted relative risk, 1.5-1.8), gestational diabetes (range, 1.8-2.9), and large (> 90th percentile) for gestational age infants (range, 1.8-2.2). From the earliest 5-year period (1980-1984) to the most recent (1995-1999), the percentage of obesity-attributable cesarean deliveries more than tripled from 3.9 to 11.6. Similar percentage increases were observed for the obesity-attributable risks for gestational diabetes (12.8-29.6) and large for gestational age infants (6.5-19.1). Trends for secondary obesity definitions were similar, although the magnitude of the increased attributable risks was smaller. CONCLUSIONS: Efforts to reduce the frequency of certain perinatal morbidities will be constrained unless effective measures to prevent, or limit the risks of, maternal obesity are developed and implemented.

Active phase labor arrest: revisiting the 2-hour minimum.

OBJECTIVE: To generate contemporary uterine activity and labor progress data for oxytocin-augmented labor, and assess whether 2 hours of active phase labor arrest with at least 200 Montevideo units justifies cesarean delivery. METHODS: Five hundred and one consecutive spontaneously laboring term women with abnormally progressive labor were managed by a standardized protocol: oxytocin and intrauterine pressure catheter with an intent to sustain at least 200 Montevideo units for 4 hours or more before cesarean for labor arrest. Uterine activity was measured, and maternal and neonatal outcomes were evaluated. With a sample of this size, the upper 95% confidence interval limit for an event with an observed rate of 1% is below 3%. RESULTS: During oxytocin augmentation, nulliparas who were delivered vaginally dilated at a median rate of 1.4 cm/hour versus 1.8 cm/hour for parous women. In both groups, the 5th percentile of cervical dilation rate was 0.5 cm/hour. Thirty-eight women experienced labor arrest for over 2 hours despite at least 200 sustained Montevideo units; 23 (61%) achieved a vaginal delivery. Rates of chorioamnionitis and endometritis for the 38 women were 26%. None of their infants sustained a serious complication, including brachial plexus injury, even though three of the 23 vaginal deliveries (13%) were complicated by shoulder dystocia. CONCLUSION: These data demonstrate that oxytocin-augmented labor proceeds at substantially slower rates than spontaneous labor, and support our previous contention that the criteria of labor arrest for 2 hours, despite at least 200 sustained Montevideo units, are insufficiently rigorous for the performance of cesarean.

Magnesium sulfate as a tocolytic agent.

Although magnesium sulfate is widely used as a tocolytic agent in the hope of preventing spontaneous preterm birth, there is a paucity of data from large well-designed randomized clinical studies demonstrating the efficacy of magnesium sulfate therapy. Given the potential for untoward side effects and the inherent risks of magnesium sulfate therapy, a thorough understanding of the potential risks and benefits of this agent is needed. To accomplish this understanding we have provided a detailed review the history, pharmacology, physiology, maternal/fetal side effects, and tocolytic efficacy of magnesium sulfate.

Criteria for failed labor induction: prospective evaluation of a standardized protocol.

OBJECTIVE: To assess the safety and efficacy of a protocol that mandated at least 12 hours of oxytocin administration after membrane rupture before cesarean delivery for failed labor induction in the latent phase. METHODS: Gravidas at or beyond 36 weeks' gestation undergoing indicated induction with cervical dilatation up to 2 cm were studied prospectively. Prior cesarean was an exclusion criterion. If the fetal heart rate pattern was reassuring, cesarean was not permitted before the active phase of labor (4-cm dilatation and at least 90% effacement or 5-cm dilatation regardless of effacement) unless the membranes had been ruptured and oxytocin administered for at least 12 hours. RESULTS: Five hundred nine women were treated according to protocol; 360 (71%) were nulliparas and 149 (29%) were parous. Twenty-five percent of nulliparas and 9% of parous women were delivered by cesarean. After 6 hours of ruptured membranes and oxytocin, 14% of nulliparas were still in the latent phase; 39% of whom delivered vaginally, compared with 7% still in the latent phase after 9 hours (vaginal delivery rate 28%), and 4% after 12 hours (vaginal delivery rate 13%). In contrast, after 6 hours of ruptured membranes and oxytocin, only five (3%) parous women were still in the latent phase. Among those, none remained in the latent phase for 12 hours and all were delivered vaginally. No women had serious complications. Severe neonatal morbidities were infrequent and not related to duration of the latent phase. CONCLUSION: By requiring a minimum of 12 hours of oxytocin after membrane rupture before failed labor induction could be diagnosed, many nulliparas who remained in the latent phase at 6 and 9 hours had safe vaginal deliveries, and failed labor induction was eliminated as an indication for cesarean in parous women.

Cost-effective use of nevirapine to prevent vertical HIV transmission in sub-Saharan Africa.

OBJECTIVE: To assess the cost-effectiveness of alternative strategies of nevirapine (NVP) administration to prevent vertical HIV transmission in sub-Saharan Africa. DESIGN: A decision-analysis model was constructed to estimate the costs and effects of NVP-based prevention strategies for two separate groups of women: those who qualify for standard therapy by attending a 36-week prenatal visit, and those who do not qualify, owing to preterm delivery or lack of prenatal care. RESULTS: For women in prenatal care, mass provision of NVP without maternal serodiagnosis was found to yield greater health gains at an acceptable cost, compared with providing targeted therapy to only those women identified as seropositive. However, this conclusion was strongly contingent on several uncertain assumptions, most importantly the probability that a woman who does not know her serostatus will nonetheless adhere to therapy. Among those women who present for delivery without prior enrollment in a prenatal strategy, either late provision of maternal-infant NVP or treatment of only the infant would likely be a cost-effective alternative to the current practice of offering no preventive therapy. CONCLUSIONS: NVP intervention offers a cost-effective avenue for preventing vertical HIV transmission in sub-Saharan Africa. The optimal choice between mass therapy and targeted therapy cannot be confidently identified without information regarding adherence among women who do not know their serostatus. For women who do not receive NVP prenatally, treatment on presentation for delivery would be cost-effective even in the face of modest clinical efficacy. Clinical assessment of adherence to therapy among women who do not know their status and the field effectiveness of alternative approaches to NVP administration is urgently needed to allow identification of optimal prevention strategies.

An appraisal of screening for maternal type-specific herpes simplex virus antibodies to prevent neonatal herpes.

Almost all neonatal herpes simplex virus infections occur as a result of first-episode maternal infection during late pregnancy when delivery occurs before the development of protective maternal antibodies. Screening of pregnant women for the presence of type-specific herpes simplex virus antibodies has therefore been suggested as a means of identifying women vulnerable to herpes simplex virus acquisition and subsequent transmission of herpes simplex virus to their neonates. Couples in whom herpes simplex virus serotype discordance is identified could be counseled regarding sexual behavior modification to avoid maternal herpes simplex virus infection. However, the ramifications of routine screening for herpes simplex virus susceptibility during pregnancy could be profound in terms of costs, prenatal care delivery, and even social duress. The recent US Food and Drug Administration approval of type-specific herpes simplex virus antibody assays for clinical use lends temporal urgency to the need for a critical examination of the relevant data. After we performed such an evaluation and created a decision analysis model to assess the potential cost-effectiveness of herpes simplex virus antibody screening, we concluded that screening for maternal type-specific herpes simplex virus antibodies cannot be recommended to prevent neonatal herpes.

Prophylactic cesarean delivery for fetal macrosomia diagnosed by means of ultrasonography--A Faustian bargain?

Both our previously performed decision analysis and more recent clinical data considered in the context of our decision analytic framework support the claim that in the pregnancies of women without diabetes the level of intervention and the economic costs of prophylactic cesarean delivery for fetal macrosomia diagnosed by means of ultrasonography are predicted to be excessive. Under the most plausible assumptions, a prophylactic cesarean policy with either a 4000- or 4500-g macrosomia threshold would require more than 1000 cesarean deliveries and millions of dollars to avert a single permanent brachial plexus injury. In the pregnancies of diabetic women, although such policies would be expected to perform appreciably better, their use would nevertheless entail considerable intervention for any benefit achieved. Under most assumptions, hundreds of cesarean deliveries and hundreds of thousands of dollars would be required to avert a single permanent brachial plexus injury. In light of the available data, optimizing the management of shoulder dystocia seems at present to be the most immediate and tenable approach to the prevention of birth-related brachial plexus injury.

Rapid testing and zidovudine treatment to prevent vertical transmission of human immunodeficiency virus in unregistered parturients: a cost-effectiveness analysis.

OBJECTIVE: To assess the potential effectiveness and costs of a program to prevent vertical transmission of human immunodeficiency virus (HIV) in parturients without prenatal care. METHODS: A decision-analysis model was constructed to compare three management strategies for unregistered women presenting in labor: 1) the current standard of treating no one; 2) HIV testing with a rapid antibody assay, followed by zidovudine treatment according to AIDS Clinical Trial Group Protocol 076 if seropositive; and 3) treating all women without rapid testing. Cost and probability data were obtained from a literature review and local estimates. Sensitivity analyses were performed for pertinent uncertainties. RESULTS: Under baseline assumptions (5% HIV prevalence, treatment efficacy of an 18% reduction in transmission rate, and lifetime cost of pediatric HIV $103,708), giving no treatment resulted in 1275 infected infants per 100,000 mother-infant pairs. The rapid-test strategy prevented 183 cases of infant HIV infection and resulted in a net savings to the medical system of $57,997 per case averted. The treat-all strategy prevented an additional 46 cases per 100,000 mother-infant pairs, but at a cost of $342,068 per additional case averted. With other estimates at baseline, rapid testing was cost-saving when the HIV prevalence exceeded 0.97%, the treatment efficacy exceeded a 5.8% reduction in the transmission rate, and the lifetime cost of pediatric HIV infection exceeded $33,625. CONCLUSION: Rapid HIV testing of unregistered parturients followed by zidovudine treatment if seropositive would be cost saving to the medical system.