Maternal Infection Rates Research Articles

Antibiotic Prophylaxis in Premature Rupture of Membranes at Term

To determine whether prophylactic antibiotic administration in women presenting with premature rupture of membranes (PROM) at term can alter the rates of maternal and neonatal infections. In a randomized, controlled, nonblinded trial, women at low risk with singleton term pregnancies presenting with PROM were assigned to either antibiotic administration or no treatment. Main outcomes evaluated were rates of maternal infection (chorioamnionitis and endometritis) and neonatal infection. A total of 161 patients were evaluated, 78 in the antibiotic group and 83 in the control group. Maternal infection was significantly lower when antibiotics were administered (2.6% compared with 13.2%; relative risk 0.89, 95% confidence interval 0.81-0.98; P=.013). All cases of maternal infection occurred in women with more than 12 hours of PROM. Newborns of mothers receiving antibiotics had fewer infections (3.8%) compared with those in the control group (6.0%), but the difference was not statistically significant (P=.375). Prophylactic use of antibiotics in PROM at term significantly reduced the risk of maternal infection in our population. ClinicalTrials.gov, www.clinicaltrials.gov, NCT01633294. I.

Maintaining Perioperative Normothermia in the Patient Undergoing Cesarean Delivery

Anesthesia and surgery interfere with normal thermoregulation, and nearly all patients will become hypothermic unless compensatory measures are used. Preoperative patient warming and intraoperative methods using forced air and warmed intravenous fluids are important methods for maintaining patient's core temperature during the perioperative period. The benefits of maintaining normothermia include reductions in postoperative wound infection, the risk of perioperative coagulopathy, and myocardial ischemia. These advantages, demonstrated in patients undergoing general surgery, would be expected in patients undergoing gynecological surgery but have not been specifically studied in that population. Few studies have examined the maternal and neonatal effects of hypothermia after cesarean delivery. The results conflict as to the effectiveness of maternal warming techniques used to prevent it and the effects on neonatal temperature and acid-base status at delivery. Large prospective studies will be required to show significant effects on rates of maternal wound infection after cesarean delivery. European and American national obstetrical organizations have not published recommendations regarding the perioperative thermal regulation for cesarean delivery. We review the physiology of thermal regulation and perioperative thermal management in surgical patients and the literature that has examined perioperative maternal warming for cesarean delivery.

Prenatal Toxoplasma gondii

Prenatal Toxoplasma gondii

Group B Streptococcal Infection in Taiwan: Maternal Colonization and Neonatal Infection

There is no national data on group B streptococcus (GBS) infection in Taiwan. We investigated incidence of maternal GBS colonization and neonatal GBS infection rate and clinical pictures of neonatal GBS infection to estimate the value of intrapartum chemoprophylactic strategy in Taiwan. From January 2004 to June 2005, a prospective study to estimate maternal colonization rate by maternal rectovaginal culture at six hospitals was conducted. Neonatal GBS infection rate based on inborn infants was calculated retrospectively from January 2001 to June 2005; clinical pictures of infants diagnosed with invasive GBS disease were reviewed. Maternal colonization rate of GBS was around 20% at hospital base, incidence of neonatal GBS infection was 1 per 1000 live births of infants born at hospitals. There were 221 infants with GBS infection: in 142, the disease occurred within 7 days of birth (early-onset disease, EOD), and in 79, it developed later (late-onset disease). Infantile EOD was more often seen in mothers with premature rupture of membrane, often accompanied by respiratory failure necessitating ventilator support. Infants with late-onset disease often manifested fever, leukopenia, thrombocytopenia, and meningitis. Fifteen infants died, mostly of EOD type (12 of 15). Risk factors of mortality included rescue at delivery room, leukopenia, thrombocytopenia, sepsis, respiratory distress, persistent hypertension of newborn, respiratory failure needing intensive respiratory support (intermittent mandatory ventilator and high frequency oscillatory ventilator), surfactant use, shock, and congenital heart diseases. We concluded that universal maternal rectovaginal culture of GBS with intrapartum antibiotic prophylaxis is an urgent call to reduce EOD and mortality because of GBS infection in neonates in Taiwan.

Safe spinal anesthesia in a woman with chronic renal failure and placenta previa

Chronic renal failure is strongly associated with poor pregnancy outcome. Women dependent on hemodialysis before conception rarely achieve a successful live birth. A 31-year-old multiparous Turkish woman was scheduled for cesarean section under spinal anesthesia at 37 weeks and five days' gestation because of hemorrhage due to secondary placenta previa. Spinal anesthesia with 8 mg of hyperbaric bupivacaine was successfully performed. Invasive blood pressure, central venous pressure, and heart rate were stable during the surgery. The mother returned to regular hemodialysis on the first postoperative day. Pregnancy is uncommon in women with chronic renal failure requiring chronic dialysis. Rates of maternal hypertension, pre-eclampsia, anemia, and infection in the pregnant chronic dialysis patient are high. However, our findings suggest that with careful, close, and effective monitoring preoperatively and intraoperatively, spinal anesthesia can be safely performed for cesarean section in patients undergoing hemodialysis.

Maternal infection rates after cesarean delivery by Pfannenstiel or Joel–Cohen incision: A multicenter surveillance study

Objective Our purpose was to evaluate maternal nosocomial infection rates according to the incision technique used for caesarean delivery, in a routine surveillance study. Study design This was a prospective study of 5123 cesarean deliveries (43.2% Joel–Cohen, 56.8% Pfannenstiel incisions) in 35 maternity units (Mater Sud Est network). Data on routine surveillance variables, operative duration, and three additional variables (manual removal of the placenta, uterine exteriorization, and/or cleaning of the parieto-colic gutter) were collected. Multiple logistic regression analysis was used to identify independent risk factors for infection. Results The overall nosocomial infection and endometritis rates were higher for the Joel–Cohen than Pfannenstiel incision (4.5% vs. 3.3%, 0.8% vs. 0.3%, respectively). The higher rate of nosocomial infections with the Joel–Cohen incision was due to a greater proportion of patients presenting risk factors (i.e., emergency delivery, primary cesarean, blood loss ≥800 mL, no manual removal of the placenta and no uterine exteriorization). However, the Joel–Cohen technique was an independent risk factor for endometritis. Conclusion The Joel–Cohen technique is faster than the Pfannenstiel technique but is associated with a higher incidence of endometritis.

Maternal and neonatal infections and obstetrical outcome in water birth

Objectives The goal of our study was to assess the effect of water birth on obstetrical outcome, the maternal and neonatal infection rate in a selected low risk collective. Study design In this prospective observational study (1998–2002) 513 women, wished to have a water birth. The study was approved by the local ethical committee, informed consent was obtained. According to the course of delivery, we compared three groups: woman who had a water birth, a normal vaginal delivery after immersion and a normal vaginal delivery without immersion. Outcome measurements were maternal and fetal infection rate, obstetrical outcome parameters and relevant laboratory parameters. Results The groups were comparable in terms of demographic and obstetric data. The maternal and neonatal infection rate and laboratory parameters showed no significant difference among the groups. There was no maternal infection related to water birth. There were five water born neonates and three neonates after normal vaginal delivery preceded by immersion with conjunctivitis. Significant differences were observed in obstetrical outcome parameters: less use of analgesia, shorter duration of first and second stage of labor, smaller episiotomy rate in water birth. In contrast no differences were seen in all observed fetal outcome parameters: APGAR score, arterial and venous pH, admission rate to neonatal intensive care unit. Conclusions Water birth is a valuable alternative to traditional delivery. The maternal and fetal infection rate was comparable to traditional deliveries. A careful selection of a low risk collective is essential to minimize potential risks.

Intermittent Preventive Treatment in Infants—Adjusting Expectations and Seeing Opportunity

Antimalarial drugs have long been used to treat acute cases of malaria to cure infection and to prevent disease progression severe disease and death. They have also been used to prevent illness (e.g. chemoprophylaxis) and to reduce transmission (e.g. mass drug administration coupled with vector control measures). With each preventive strategy the balance of efficacy and long-term feasibility has led to progressively more focused use of the drug. That is mass drug administration and broad use of chemoprophylaxis in a population have been reduced to targeted drug administration to fewer people and only specific groups or to shorter time intervals to maximize benefits and to reduce costs poor adherence and the potential impact on drug resistance. Among pregnant women in settings where malaria is endemic who have long been a target population for chemoprophylaxis studies have demonstrated that a few treatment doses of a safe and efficacious antimalarial at intervals linked to routine antenatal clinic visits could produce a substantial reduction in rates of maternal anemia placental parasite infection and the attendant risk of low birth weight. This proactive and presumptive (not linked to symptoms or documentation of infection) use of treatment doses at a few specific intervals which is known as intermittent preventive treatment (IPT) during pregnancy has been widely adopted in many sub-Saharan African countries. (excerpt)

Quality of obstetric care and risk-adjusted primary cesarean delivery rates

The purpose of this study was to examine the association between risk-adjusted primary cesarean delivery rates and maternal and neonatal outcomes. California birth certificate data that were linked to hospital discharge data for 2001 were used to create a primary cesarean delivery rate risk-adjustment model. Two hundred eighty-five hospitals were divided into 3 groups that were above, below, or within expected rate confidence intervals. Maternal and neonatal outcomes were compared within each of the 3 hospital groupings. Of the 285 hospitals, 27% had primary cesarean delivery rates that were above expected confidence intervals; 34% had primary cesarean delivery rates that were below expected confidence intervals, and 39% had primary cesarean delivery rates that were within expected confidence intervals. Neonatal asphyxia rates were higher in hospitals that had lower than expected rates of cesarean deliveries (0.05%, 0.1%, 0.07% for above, below, and within the confidence intervals, respectively; P < .0001). Maternal infection rates (2.1%, 2.3%, 1.8%, respectively; P < .0001) and third-degree tears (2.3%, 3.0%, 2.6%, respectively; P < .0001) were also higher in hospitals for which the cesarean delivery rates were above or below the expected rates. Risk-adjusted primary cesarean delivery rates are a good marker for maternal and neonatal outcomes.

A study on the traditional Chinese medicine Jinyebaidu for prevention and treatment of intrauterine infection with guinea pigs cytomegalovirus.

The purpose is to study the prophylactic and therapeutic effect of the traditional Chinese Medicine (TCM)-Jinyebaidu (JYBD) to guinea pig cytomegalovirus (GPCMV) intrauterine infection. The virus-free female and male guinea pigs were screened with nest-polymerase chain reaction (N-PCR). After inbred, pregnant guinea pigs were selected and divided into 3 groups randomly: 5 guniea pigs of the blank control group were not given either GPCMV or JYBD. 31 guniea pigs of the positive control group were inoculated 1 mL (10(7) TCID50) suspension of GPCMV intraperitoneal. 10 guniea pigs of the experimental group were inoculated GPCMV firstly and then perfused stomach with JYBD for 14 days (Dosage in accordance with the modulus of the weight ratio of human to guniea pig). The effects of JYBD on the intrauterine infection of GPCMV were observed. The results showed that JYBD could decrease the maternal infection rate from 100% (31/31) to 50% (5/10) (P < 0.001), the intrauterine infection rate from 100% (72/72) to 75% (21/28) (P < 0.001), and the rate of abnormal outcome of pregnancy from 64.4% (29/45) to 25.0% (7/28) (P < 0.001), the infective symptoms being relieved. It can be concluded that traditional Chinese medicine- JYBD can prevent and treat (GPCMV intrauterine infection, and can be expected a prophylactic drug for HCMV intrauterine infection.

Hospital Rates of Maternal and Neonatal Infection in a Low-Risk Population

In 2003, the Agency for Healthcare Quality and Research (AHRQ) published its Quality Indicators for healthcare, and set out methodological criteria for the evaluation of potential candidates. Because perinatal infections may result from poor obstetrical practices, we intended to describe the variability of maternal and congenital neonatal infections across different types of hospital ownership (e.g., not for profit, government), and to assess whether rates of these infections meet criteria as quality indicators. Population-based cohort study. All laboring women without maternal, fetal, or placental complications who delivered in California in 1997, and their neonates, as reported through hospital discharge data. A Bayesian hierarchical logistic regression model was used to quantify the effects of both "patient-level" risk factors such as parity and prior cesarean history, and "hospital-level" risk factors such as ownership and teaching status. The 308,841 mother-newborn pairs in this low-risk study population delivered at 281 hospitals; 0.39% had uterine infections and 1.3% had neonatal infections. Hospital ownership and teaching status were strongly associated with perinatal infection. Secondly, methods used to estimate and analyze hospital-specific infection rates identified hospitals with exceptionally high rates. Twenty-eight hospitals had neonatal infection rates that ranged from 3% to 28%. The methods presented here were consistent with AHRQ methods and criteria for potential Quality Indicators. They also identified hospitals with exceptionally high rates of infectious morbidity. The relationship between hospital ownership and obstetrical practice patterns, and the feasibility of practice improvement, remain to be studied.

The impact of clinical management type on maternal and neo-natal outcome following pre-labour rupture of membranes at term

To investigate the impact of home compared to hospital conservative management on maternal and neonatal outcome on women with pre-labour rupture of membranes (PROM) at term. A randomised, controlled trial, participants were randomly allocated to one of the following two arms of clinical intervention, hospital management group (N = 27) or home management group (N = 29). The dependent variables were established clinical indices of maternal and neonatal outcome. 56 women admitted to the maternity unit of a north east England maternity hospital with confirmed PROM. All participants were over 37 weeks gestation (mean 39.08, SD 1.08), with a singleton pregnancy of cephalic presentation and no apparent medical or obstetric contra-indications and absence of uterine contractions. No significant differences were found between groups in maternal high vaginal swab infection rates, neonatal infection screen or Apgar scores. No other statistically significant differences between groups were observed on any of the key clinical outcome maternal or neonatal indices. This study provides empirical evidence that women allowed home for the period of expectant management are at no greater risk from adverse maternal or neonatal outcomes than their counterparts who remained in hospital. This has important clinical implications for the management of PROM at term. The direction of future research in this area is indicated.

Multiple Courses of Antenatal Steroids

In Brief OBJECTIVE To review the existing literature regarding the effect of multiple courses of antenatal corticosteroids in reducing the occurrence of complications arising because of lung immaturity. DATA SOURCES A systematic review of the English-language literature was conducted using a computerized database. We searched the English-language human and animal literature in MEDLINE and PubMed (National Library of Medicine, Bethesda, MD), as well as abstracts from recent meetings of the Society for Gynecologic Investigation and the Society for Maternal-Fetal Medicine. The search terms used were antenatal steroids, prenatal steroids, and respiratory distress syndrome. STUDY SELECTION We screened 2472 abstracts and found 280 relevant articles, which we independently reviewed. Only prospective well-designed animal studies were included. In humans, no well-designed randomized controlled trials (RCTs) were identified. Data that specifically addressed the issue of beneficial and adverse outcome of multiple courses of antenatal corticosteroids were included. TABULATION, INTEGRATION, AND RESULTS Twelve studies and three abstracts concerning animal models were included. These suggest multiple adverse consequences including decrease in birth and lung weights and brain growth restriction. In humans, 14 publications and five abstracts, mostly in the form of retrospective studies, although methodologicaly lacking, were included. Possible beneficial effects include lower rates of respiratory distress syndrome and a decrease in oxygen use, whereas adverse outcomes embody reduction in birth head circumference, birth weights, and increased neonatal and maternal infection rates. CONCLUSION To date, there are no well-designed RCTs in humans that support the advantages of multiple courses over a single course of antenatal corticosteroids. An increasing body of evidence raises the concern of adverse consequences from the use of repeated courses. While awaiting results from RCTs in progress, we recommend that a single course of antenatal corticosteroids be given to all women at risk for preterm birth at 24–34 weeks' gestation. Repeated doses of antenatal steroids for fetal lung maturation may have multiple adverse consequences with no clear benefit over a single course.

Timing of cerclage removal after preterm premature rupture of membranes: Maternal and neonatal outcomes

Objective: Our aim was to evaluate immediate versus delayed removal of cerclage for women with preterm premature rupture of membranes with respect to maternal and neonatal outcomes. Study Design: We retrospectively analyzed women with preterm premature rupture of membranes at <34 weeks’ gestation with prior cerclage placement. Exclusion criteria included presentation with chorioamnionitis, active labor, or nonreassuring fetal status. Timing of cerclage removal, immediate (<24 hours) or delayed (>24 hours), was compared. Results: There were 25 women in the delayed-removal group and 37 in the immediate-removal group. Average times to removal were 206.8 ± 7.4 and 5.4 ± 0.2 hours, respectively. Use of betamethasone was similar for both groups; however, antenatal antibiotic use (100% vs 80%; P = .03) and short-term tocolytic use (20% vs 3%; P = .04) were higher in the delayed-removal group. Duration of latency was significantly longer with delayed removal (10.1 vs 5.0 days; P < .001). Delivery occurred >48 hours from preterm premature rupture of membranes in 96% (24/25) versus 54% (20/37; P < .001) and >7 days from rupture in 56% (14/25) versus 24% (9/37; P = .02), respectively. Rates of neonatal sepsis (at <10 days) and maternal infection were not statistically different. Neonatal outcomes did not significantly differ regarding mortality, respiratory distress syndrome, birth weight, or duration of stay in the intensive care nursery. Conclusion: With the current management scheme for preterm premature rupture of membranes, cerclage retention significantly increases duration of latency without significantly altering maternal or neonatal outcomes. (Am J Obstet Gynecol 2000;183:847-52.)

Expanded-spectrum antibiotics with preterm premature rupture of membranes

Objective: To compare maternal infection rates, neonatal sepsis rates, and bacterial resistance patterns in cases of neonatal sepsis for three antibiotic protocols for women with preterm premature rupture of membranes (PROM). Methods: From January 1, 1988 to February 28, 1998, women with preterm PROM not requiring immediate delivery were treated according to one of three antibiotic protocols. During three distinct periods, patients received no antibiotics, intravenous ampicillin for 48 hours followed by oral amoxicillin, or intravenous ticarcillin-clavulanic acid for 48 hours followed by oral amoxicillin-clavulanic acid. Rates of chorioamnionitis, endometritis, and neonatal sepsis were compared, as were antimicrobial resistance patterns. Statistical analysis was done using χ 2 analysis, Fisher exact test, and the log-likelihood ratio test. The Bonferroni correction was used for multiple comparisons. Results: During the three periods, preterm PROM was diagnosed in 1695 women. The incidence of endometritis was lower during the third (5.3%) compared with the first (15.1%, P < .001) and second (11.6%, P < .001) protocols. Chorioamnionitis rates were 13.6%, 12.7%, and 15.6% ( P = .34) for the first, second, and third periods, respectively, and neonatal sepsis rates were 2.2%, 0.6%, and 1.1% ( P = .08), respectively. Neonatal sepsis with gram-negative ( P = .02) and ampicillin-resistant ( P = .04) organisms was more likely when mothers received antepartum ampicillin or ticarcillin-clavulanic acid. Conclusion: Antibiotic therapy for patients with preterm PROM was associated with a decrease in the rate of endometritis and a trend toward less neonatal sepsis but an increase in the proportion of gram-negative and ampicillin-resistant organisms causing neonatal sepsis.

Hydrotherapy Use During Labor: An Integrative Review

Hydrotherapy is an effective, alternative intervention that can be used by care providers to provide a nonpharmacological method to assist low risk, laboring women cope with labor. This article provides a synthesis of the state of the science on the effects of hydrotherapy with labor and delivery. The indications, physiologic mechanism, benefits, practice implications, and needed research are discussed. The data-based articles support numerous benefits such as increased relaxation, increased satisfaction, lower blood pressure, and increased diuresis with women who bathe during labor. These studies found that there was no difference in maternal and neonatal morbidity such as infections between bathers and nonbathers. Additionally, there was no difference in maternal and neonatal infection rates between women with intact or ruptured membranes. The use of hydrotherapy during established labor increases cervical dilation while bathing although there is no difference in the total length of labor between bathers and nonbathers. Researchers conclude that hydrotherapy is a safe, nonpharmacological alternative for women to use during labor and delivery.

Maternal and neonatal infection rates with three different protocols for prevention of group B streptococcal disease

Objectives: We compared maternal and neonatal infection rates under 3 different group B streptococcal prevention strategies and also evaluated reasons for each protocol’s failures in preventing neonatal disease. Study Design: Women who were delivered at our center from August 1, 1991, through April 30, 1998, were managed by 1 of 3 protocols for prevention of early-onset neonatal group B streptococcal infection: a selective screening protocol, The American College of Obstetricians and Gynecologists protocol, and the Centers for Disease Control and Prevention–recommended universal screening strategy. We compared maternal infection rates and neonatal group B streptococcal infection rates under each protocol. We also compared reasons for each protocol’s failures in preventing neonatal infection. Results: Clinical chorioamnionitis rates were 7.4% with selective screening, 7.7% under The American College of Obstetricians and Gynecologists’ protocol, and 5.2% with universal screening (relative risk 0.7, 95% confidence interval 0.6-0.8). Endometritis rates were 4.0% with selective screening, 4.6% with The American College of Obstetricians and Gynecologists protocol, and 2.8% with universal screening (relative risk 0.7, 95% confidence interval 0.6-0.8). Overall neonatal group B streptococcal infection rates were lower under the 2 more recent strategies, but not significantly so. Despite the ability of universal screening to find more women at risk for group B streptococcal transmission, half of the neonatal infections under this protocol occurred when the mothers were not considered candidates for prophylaxis. Conclusions: The Centers for Disease Control and Prevention–endorsed universal screening strategy for group B streptococcal infection prevention was associated with significantly lower rates of clinical chorioamnionitis and endometritis than were the other strategies. We were unable to document statistically significant improvement in neonatal outcome under the universal screening protocol. (Am J Obstet Gynecol 1999;180:416-22.)

Prophylactic Cefazolin in Amnioinfusions Administered for Meconium‐Stained Amniotic Fluid

Objective: To determine if amnioinfusion with an antibiotic solution decreased the rate of clinical chorioamnionitis and puerperal endometritis in patients with meconium‐stained amniotic fluid.Methods: Patients in labor at 36 weeks of gestation or greater with singleton pregnancies and meconium‐stained amniotic fluid were randomized to receive either cefazolin, 1 g/l,000 mL, of normal saline (n = 90) or normal saline (n = 93) amnioinfusion. Rates of clinically diagnosed chorioamnionitis and endometritis and of suspected and culture‐proven neonatal infection were determined.Results: Between the study and control groups, the incidences of clinical chorioamnionitis (7.8% vs. 8.6%), endometritis (2.4% vs. 3.5%), aggregate intrauterine infection (10.0% vs. 11.8%), suspected neonatal infection (17.8% vs. 21.5%), and proven neonatal infection (0.0% vs. 2.2%) were not significantly different.Conclusions: Prophylactic use of cefazolin in amnioinfusions did not significantly reduce rates of maternal or neonatal infection in patients with meconium‐stained amniotic fluid. Infect. Dis. Obstet. Gynecol. 7:153–157, 1999.

Meta-Analysis of Low-Dose versus High-Dose Oxytocin for Labour Induction

Many trials have attempted to determine the best dose of oxytocin for labour induction. This meta-analysis reviews and summarizes the results of all published English language randomized trials (and two unpublished trials) of low-dose versus high-dose oxytocin administration. The 11 trials identified underwent quality assessment, and data were abstracted from each study. Low-dose protocols resulted in fewer episodes of excessive uterine activity (summary odds ratio [OR] 0.41, 95 percent confidence interval [CI] 0.33–0.52), fewer operative vaginal deliveries (OR 0.58, 95 percent CI 0.40–0.83), a higher rate of spontaneous vaginal delivery (OR 1.67, 95 percent CI 1.27–2.20) and a trend toward a lower rate of Caesarean delivery (OR 0.78, 95 percent CI 0.60–1.02). There were lower rates of post-partum maternal infection (OR 0.57, 95 percent CI 0.32–0.99) and post-partum haemorrhage (OR 0.42, 95 percent CI 0.24–0.74) in the low-dose group. Although the ideal regimen is not known, induction of labour with the minimum dose of oxytocin to achieve active labour, increasing intervals no more frequently than every 30 minutes, is appropriate.

Ampicillin-Metronidazole Treatment in Idiopathic Preterm Labour

Objective To determine whether treatment with ampicillin and metronidazole in women with threatened idiopathic preterm labour will prolong the gestation and reduce maternal and neonatal infectious morbidity. Design Randomised controlled double-blind trial. Setting Six obstetric departments in the Copenhagen area. Population One hundred and twelve women with singleton pregnancies, with threatened idiopathic preterm labour and intact amniotic membranes at 26 to 34 weeks of gestation. Methods Random allocation to eight days intravenous and oral treatment with ampicillin and metronidazole, or placebo. Main outcome measures Number of days from admission to delivery, gestational age at delivery, rates of preterm delivery, low birthweight, maternal infections and neonatal infections. Results Treatment with ampicillin and metronidazole was associated with a significant prolongation of pregnancy (admission to delivery 47.5 days versus 27 days, P < 0.05), higher gestational age at delivery (37 weeks versus 34 weeks, P < 0.05), decreased incidence of preterm birth (42%versus 65%, P < 0.05), and lower rate of admission to neonatal intensive care unit (40%versus 63%, P < 0.05), when compared with placebo treatment. Antibiotic treatment had no significant effects on infectious morbidity. Conclusions Treatment with ampicillin and metronidazole in women with threatened idiopathic preterm labour significantly prolonged the gestation, but had no effects on maternal and neonatal infectious morbidity.