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PubMed2004

Role of ERK1/2 in uterine contractility and preterm labor in rats.

The present study tested the hypothesis that ERK activation is an essential step in the onset of labor in a rat model of preterm labor. The administration of RU-486, an antiprogesterone agent, to rats induced preterm delivery 22.2 +/- 0.24 h after treatment. Changes in basal signaling events were studied in myometrial tissue from CO(2)-euthanized rats. Rats treated with RU-486 displayed a dramatically increased in vitro uterine contractility compared with gestational stage-matched, sham-treated rats. In vitro contractility was not significantly different from that during spontaneous labor. During RU-486-induced preterm labor, as previously described for spontaneous labor, ERK phosphorylation levels increased, as did phosphorylation of caldesmon at Ser(789), an ERK phosphorylation site. Also, a small but significant increase in 20-kDa myosin light chain phosphorylation was seen at a constant intracellular pCa of 7. When rats were chronically treated with an agent that prevents ERK activation, U-0126, the onset of RU-486-induced preterm labor was delayed in a statistically significant manner. Chronic in vivo treatment with U-0126 also significantly inhibited the RU-486-induced increase in in vitro contractility and ERK and caldesmon phosphorylation but did not alter the RU-486-induced increase in 20-kDa myosin light chain phosphorylation. These data indicate that ERK activation is a component of the multiple events leading to the development of labor in this rat model. We suggest that the ERK pathway could possibly be used to identify targets for the development of a novel class of tocolytic agents.

Animals↗
PubMed2006

A meta-analysis of labor supply effects of interventions for major depressive disorder.

OBJECTIVE: The aims of this study were to examine labor supply effects of interventions for major depressive disorder and to compare these effects with a summary measure of clinical effectiveness. METHODS: Research articles published in English-language journals from 1980 through May 2004 were searched by using five research databases. Only randomized trials that included a placebo group or a usual care group were eligible for the study, regardless of the specific type of intervention. Valid trials were those that enrolled adult patients with major depressive disorder and assessed changes in labor output by using a measure of time worked or labor market participation. From a total of 706 trials uncovered from the database searches, only four met all inclusion criteria. Trial outcomes were transformed into standardized effect sizes on the basis of Cohen's d. Hierarchical linear models were used to separately pool work outcomes and clinical outcomes. RESULTS: An improvement of .34 standard deviation was found in the size of the clinical effect of interventions compared with placebo or usual care among 1,261 unique patients with depression. An improvement of .12 standard deviation was found in the size of the effect on labor supply among 1,848 unique patients. CONCLUSIONS: Although the interventions studied were associated with reduced symptoms of depression and increased labor output, the labor benefits were small according to standard benchmarks used in interpreting the substantive significance of values of Cohen's d. The difference in effects may have been due to different underlying efficacies, brief durations of follow-up, or extrinsic factors that affect labor supply.

Major Depressive Disorder↗
PubMedDate not supplied

Hazardous child labor: lead and neurocognitive development.

Hazardous child labor is challenging to define and quantify in the context of acute or chronic toxic exposures--either of which may cause significant disease and disability. Epidemiologic occupational studies in adults have documented many harmful outcomes secondary to exposure to toxic substances. Occupational surveillance efforts often have focused on acute injuries because they are more readily identified. Fassa has been able to compile data concerning injuries to child laborers but notes, "There is great need for studies in developing countries ... on the impact of child labour on illness." Although injuries may be underreported or undocumented among child laborers, acute injury is, at least, potentially recordable. This is in sharp contrast to toxic exposures, where exposure assessment is usually difficult and costly. This is especially true when it is done after an exposure has taken place. The outcomes of most toxic workplace exposures to children remain unknown. The Agency for Toxic Substances and Disease Registries (ATSDR) notes that in similar environments, children may have greater exposures than adults: "Pound for pound of body weight, children drink more water, eat more food, and breathe more air than adults," and "In some instances, children are less able than adults to detoxify chemicals and are thus more vulnerable." Children who begin work at an early age have many more years to develop illness than an adult doing the same work. A household survey of child laborers in Ethiopia found that a high proportion (greater than 90%) of children in both urban and rural areas of the country reported non-use of protective equipment. However, it is the experience of present author D.P. that this equipment is rarely if ever adequate, even when made available. For example, protective equipment such as respirators or impermeable gloves are designed for adults, and thus do not properly fit children. In defining hazardous child labor, the larger context of public health cannot be ignored. The study of child labor needs to take into account the baseline health of exposed individuals. In developing countries, the poorest and most vulnerable children are most often involved in work in order to earn money for survival. These children are also likely to already lack basic necessities of food and medical care, predisposing them to diarrhea, anemia, and micronutrient deficiencies. Underlying nutritional conditions may make children more susceptible to the effects of toxic substances such as lead. In addition, child laborers also may be exposed to lead and other toxic substances from their poor living conditions.

Adolescent↗
PubMed2006

Effects of epidural lidocaine analgesia on labor and delivery: a randomized, prospective, controlled trial.

BACKGROUND: Whether epidural analgesia for labor prolongs the active-first and second labor stages and increases the risk of vacuum-assisted delivery is a controversial topic. Our study was conducted to answer the question: does lumbar epidural analgesia with lidocaine affect the progress of labor in our obstetric population? METHOD: 395 healthy, nulliparous women, at term, presented in spontaneous labor with a singleton vertex presentation. These patients were randomized to receive analgesia either, epidural with bolus doses of 1% lidocaine or intravenous, with meperidine 25 to 50 mg when their cervix was dilated to 4 centimeters. The duration of the active-first and second stages of labor and the neonatal apgar scores were recorded, in each patient. The total number of vacuum-assisted and cesarean deliveries were also measured. RESULTS: 197 women were randomized to the epidural group. 198 women were randomized to the single-dose intravenous meperidine group. There was no statistical difference in rates of vacuum-assisted delivery rate. Cesarean deliveries, as a consequence of fetal bradycardia or dystocia, did not differ significantly between the groups. Differences in the duration of the active-first and the second stages of labor were not statistically significant. The number of newborns with 1-min and 5-min Apgar scores less than 7, did not differ significantly between both analgesia groups. CONCLUSION: Epidural analgesia with 1% lidocaine does not prolong the active-first and second stages of labor and does not increase vacuum-assisted or cesarean delivery rate.

Journal Article↗
PubMed2005

Educational and labor wastage of doctors in Mexico: towards the construction of a common methodology.

BACKGROUND: This paper addresses the problem of wastage of the qualified labor force, which takes place both during the education process and when trained personnel try to find jobs in the local market. METHODS: Secondary sources were used, mainly the Statistical yearbooks of the National Association of Universities and Higher Education Institutions (ANUIES in Spanish). Also, the 2000 Population Census was used to estimate the different sources of labor market wastage. The formulas were modified to estimate educational and labor wastage rates. RESULTS: Out of every 1000 students who started a medical training in 1996, over 20% were not able to finish the training by 2000. Furthermore, out of every 1000 graduates, 31% were not able to find a remunerated position in the labor market that would enable them to put into practice the abilities and capacities obtained at school. Important differences can be observed between generalists and specialists, as well as between men and women. In the case of specialists and men, lower wastage rates can be observed as compared to the wastage rates of generalists and women. A large percentage of women dedicate themselves exclusively to household duties, which in labor terms represents a wastage of their capacity to participate in the production of formal health services. CONCLUSION: Women are becoming a majority in most medical schools, yet their participation in the labor market does not reflect the same trend. Among men, policies should be formulated to incorporate doctors in the specific health field for which they were trained. Regarding women, specific policies should target those who are dedicated full-time to household activities in order to create the possibility of having them occupy a remunerated job if they are willing to do so. Reducing wastage at both the educational and labor levels should improve the capacity of social investment, thereby increasing the capacity of the health system as a whole to provide services, particularly to those populations who are most in need.

Journal Article↗
PubMed2006

Maternal position during the first stage of labor: a systematic review.

BACKGROUND: Policy makers and health professionals are progressively using evidence-based rationale to guide their decisions. There has long been controversy regarding which maternal position is more appropriate during the first stage of labor. This problem has been examined often and repeatedly and the optimal recommendation remains unclear. METHODS: This is a systematic review of the effect of maternal position during the first stage of labor. The main question addressed here is: Does encouraging women to adopt an upright position or to ambulate during the first stage of labor reduce the duration of this stage? All randomized controlled trials carried out to assess this effect were taken into consideration in this review. The following electronic databases were accessed to identify studies: MEDLINE, Popline, the Scientific Electronic Library On-line and the Latin American and Caribbean Health Science Information. Citation eligibility was independently assessed by two reviewers. The methodological quality of each trial was also evaluated independently by two reviewers and a trial under consideration was included only when consensus had been attained. Allocation concealment and screening for the occurrence of attrition, performance and detection biases were considered when studies were appraised. The decision whether to perform data pooling was based on the clinical similarity of studies. RESULTS: The search strategy resulted in 260 citations, of which 18 were assessed in full-text. Nine eligible randomized controlled trials were included in the systematic review. Randomization methods were not fully described in eight studies. The allocation concealment was considered adequate in four studies and unclear in five. The investigators pooled the data from seven studies in which the length of the first stage of labor and results were in favor of the intervention, but the high level of heterogeneity (I2 = 88.4%) impaired the meaning of this finding. The intervention did not affect other outcomes studied (mode of delivery, use of analgesia, labor augmentation and condition of the child at birth). CONCLUSION: Adoption of the upright position or ambulation during first stage of labor may be safe, but considering the available evidence and its consistency, it cannot be recommended as an effective intervention to reduce duration of the first stage of labor.

Journal Article↗
PubMed1998

Maternal, umbilical, and amniotic fluid concentrations of tryptophan and kynurenine after labor or cesarean section.

A major route of tryptophan metabolism is via the hepatic and cerebral synthesis of kynurenine, a substance subsequently used by astrocytes in the brain for the production of the neuroactive substances kynurenic acid and quinolinic acid. Both kynurenic and quinolinic acids have been implicated in modulating the activity of excitatory amino acid pathways in the brain, the former as a neuroprotectant because of its antagonist properties, and the latter as an excitotoxin because of its agonist actions, at NMDA receptors. We therefore determined the concentrations of tryptophan and kynurenine in maternal venous and umbilical cord blood, and in amniotic fluid, of infants after labor and vaginal delivery, and after delivery by cesarean section. Concentrations of tryptophan and kynurenine were significantly higher in umbilical vein plasma compared with maternal venous plasma. Tryptophan and kynurenine concentrations in umbilical vein plasma and amniotic fluid were significantly higher after labor, compared with samples obtained from infants of the same gestational age delivered by cesarean section. There was no umbilical vein-to-artery concentration difference for kynurenine in samples obtained after either labor or cesarean section, but there was a significant gradient for tryptophan in samples obtained after vaginal delivery, indicating increased transfer of this amino acid during labor. There was a significant correlation between umbilical vein tryptophan and kynurenine concentrations for both the labor and cesarean section groups, and plasma kynurenine concentrations were also significantly correlated with both umbilical vein cortisol concentrations and the duration of the second stage of labor in the vaginally delivered infants. These results suggest that the placental transfer of tryptophan and the fetal synthesis of kynurenine are increased during labor. These findings have implications for understanding the vulnerability of the infant brain to ischemic/hypoxic damage in the perinatal period. By analogy with the adult brain, the molar ratio of these substances is likely to determine the susceptibility of the brain to seizure and excitotoxic damage.

Adult↗
PubMed2004

Epidural infusions of ropivacaine and bupivacaine for labor analgesia: a randomized, double-blind study of obstetric outcome.

UNLABELLED: Studies have shown better obstetric outcome when ropivacaine 0.25% was used for labor epidural analgesia compared with bupivacaine 0.25%, but it is controversial whether there is any difference at smaller concentrations. In a prospective, double-blind trial, we randomized 350 ASA physical status I and II parturients with term cephalic singleton pregnancies to receive epidural labor analgesia using ropivacaine or bupivacaine. Analgesia was initiated with a 0.25% solution and maintained with a continuous infusion of a 0.1% solution with fentanyl 0.0002%. Supplementary boluses of 0.25% solution were given when requested. Labor was managed according to institutional standard labor ward protocols. Among patients who delivered vaginally, the duration of the first stage of labor was shorter in the ropivacaine group (median, 520 min; interquartile range, 377-745 min) compared with the bupivacaine group (645 min; interquartile range, 460-820 min; P = 0.009), but there was no difference in any other obstetric or neonatal outcomes. The mode of delivery was similar between groups, with operative (instrumental vaginal and cesarean) delivery rates of 61.8% (95% confidence interval, 54.4%-68.8%) in the ropivacaine group and 58.4% (95% confidence interval, 50.9%-65.5%) in the bupivacaine group (P = 0.72). IMPLICATIONS: In a randomized-controlled study, we found no major outcome advantage of continuous epidural infusion of ropivacaine 0.1% with fentanyl 0.0002% over bupivacaine 0.1% with fentanyl 0.0002% for labor analgesia. Although ropivacaine was associated with a shorter first stage of labor, the relative difference is probably of limited clinical importance, and there was no difference in the mode of delivery.

Adult↗
PubMed1982

How valid are self-report measures for evaluating relationships between women's health and labor force participation?

For a sample of white women aged 45-64, women who were out of the labor force had poorer self-reported health and higher mortality than women who were in the labor force. It has been hypothesized that women who are out of the labor force may tend to exaggerate their poor health in self-report data. However, no evidence of bias of this type was found in an analysis of the relationships between self-reported health and subsequent mortality. The validity of self-reports of illness as a reason for not seeking work has been assessed using data for a sample of 30-44 year old women who were out of the labor force. Over 90% of the women who gave illness or disability as their main reason for not seeking work had previous or contemporaneous independent, self-report evidence of poor health. The findings of this study and previous evidence indicate that poor health reduces the likelihood that a woman will join the labor force, and this is a major reason why women who are not in the labor force have poorer health than those who are in the labor force.

Employment↗
PubMed1992

Markets in women's reproductive labor.

Much of the evolution of social policy in the twentieth century has occurred around conflicts over the scope of markets. To what extent, under what conditions, and for what reasons should we limit the use of markets? Recently, American society has begun to experiment with markets in women's reproductive labor. Many people believe that markets in women's reproductive labor, as exemplified by contract pregnancy, are more problematic than other currently accepted labor markets. I will call this the asymmetry thesis because its proponents believe that there ought to be an asymmetry between our treatment of reproductive labor and our treatment of other forms of labor. Advocates of the asymmetry thesis hold that treating reproductive labor as a commodity, as something subject to the supply-and-demand principles that govern economic markets, is worse than treating other types of human labor as commodities. Is the asymmetry thesis true? And, if so, what are the reasons for thinking that it is true? My aims in this article are to criticize several popular ways of defending the asymmetry thesis and to offer an alternative defense....I focus my discussion on those arguments against contract pregnancy that depend on the asymmetry thesis. I believe that the asymmetry thesis both captures strong intuitions that exist in our society and provides a plausible argument against contract pregnancy.

Adoption↗
PubMed1999

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.

Journal Article↗
PubMed2004

Does ultrasound examination when the cervix is unfavorable improve the prediction of failed labor induction?

OBJECTIVE: To compare the Bishop score, ultrasound cervical parameters and fetal fibronectin assessment for predicting failed labor induction when the cervix is unfavorable. METHOD: A prospective observational study was performed in 106 consecutive pregnant women with a Bishop score < or =5 undergoing labor induction. Assessment of fetal fibronectin and ultrasound measurement of cervical length, cervical wedging and cervical lip areas were performed. The relationship between these parameters and failure of labor induction was determined. RESULTS: Failure of labor induction was defined as failure to reach a cervical dilatation of > or =5 cm, and it occurred in 16 patients (15.1%). Induction failure was associated with low Bishop scores before (P = 0.004) and 6 h after the start of induction (P = 0.007), increased clinical cervical length (P = 0.02) and increased ultrasound anterior cervical lip area (P = 0.04). The logistic regression model identified the Bishop score before induction (odds ratio = 2.25; 95% CI, 1.30-3.91; P = 0.003) and the clinical cervical length (odds ratio = 3.95; 95% CI, 1.3-11.7; P = 0.01) as being independent predictors of failed induction. To predict an induction failure, the best Bishop score cut-off value was 4, with a sensitivity of 87.5%, a specificity of 45.6%, a likelihood ratio of 1.58, a positive predictive value of 22.2% and a negative predictive value of 95.4%. CONCLUSION: Compared with the Bishop score, cervical length by ultrasound is not a better predictor for the outcome of labor induction in an unfavorable cervix. Nevertheless, the Bishop score appears to be of poor predictive value for failed induction of labor.

Adult↗
PubMed1976

Oral prostaglandin E2 for labor induction in high-risk pregnancy.

Oral prostaglandin E2 (PGE2) was used alone or synergistically with intravenous oxytocin to induce labor in 84 women whose pregnancies were at high risk. A control group of 84 similar high-risk pregnancies where labor was induced with intravenous oxytocin alone was studied to compare the safety and efficacy of the two regimens. Oral PGE2 administration, combined with the synergistic effect of intravenous oxytocin, is safe for induction of labor in gravid women whose fetuses are at risk. Uterine polysystole, which is potentially dangerous, especially to the high-risk fetus, was not commonly encountered and only once was associated with transient fetal bradycardia. Uterine hypertonus was not encountered with PGE2; however, it did occur with oxytocin stimulation. Nausea and vomiting occurred in one third of the women treated with PGE2 but were well tolerated and required discontinuation of the drug in only one instance. There was no apparent advantage of using the combination PGE2 regimen in patients whose cervices were more favorable for induction of labor (Bishop score, 5 to 9). However, oral PGE2, used either alone or synergistically with oxytocin, appears twice as effective in inducing labor than was oxytocin alone in women in whom labor was considered to be "difficult to induce" (Bishop score, 0 to 4).

Administration, Oral↗
PubMed1984

Management of spontaneous rupture of the membranes in the absence of labor in primigravid women at term.

One hundred and thirty-five healthy primigravid women at or near term with spontaneous rupture of the membranes without uterine contractions were submitted to a prospective trial of management. Rupture of the membranes was diagnosed by speculum examination. If labor did not commence, induction was performed by oxytocin infusion starting at 9 AM following admission. One hundred and five women went into labor spontaneously before induction became necessary. Sixty-three of these women required augmentation with oxytocin. Twenty-seven percent of the induced group required cesarean section delivery compared to 10% of those in spontaneous labor augmented by oxytocin and to none of those who did not require oxytocin (p less than 0.01). Ninety-four percent of those in spontaneous labor were delivered vaginally compared to 73% of the induced group (p less than 0.01). Forty-one percent of the augmented group were delivered by forceps. Awaiting the spontaneous onset of labor for 24 hours or less did not result in clinical maternal or neonatal infection. We would therefore advocate awaiting the spontaneous onset of labor after spontaneous rupture of membranes without contractions at or near term in healthy primigravid women for up to 24 hours because it seems to confer significant advantages without producing any additional hazard.

Adolescent↗
PubMed1985

Previous cesarean section: the risks and benefits of oxytocin usage in a trial of labor.

Permitting a trial of labor in patients with a previous cesarean birth is rapidly becoming an accepted alternative to routine elective repeat cesarean section. As interest in this approach has grown and the risks associated with a trial of labor have been better defined, the use of oxytocin in these patients emerges as a pertinent issue. Our retrospective experience of oxytocin use in patients undergoing a trial of labor suggested no increased maternal or fetal risk compared to patients who did not receive oxytocin. On the basis of our prior experience, we set out to investigate prospectively the role of oxytocin in 732 patients with prior cesarean section who underwent a trial of labor. During the study period, 289 (40%) patients received oxytocin for either induction (32, 11%) or augmentation (257, 89%) of labor and 443 patients did not receive oxytocin. Successful vaginal delivery was achieved in 200 patients (69%) as opposed to 395 (89%) of the patients who did not receive oxytocin. The incidences of dehiscence in the oxytocin and no oxytocin groups were 3% and 2%, respectively. Further analysis of vaginal and cesarean delivery complications for the two groups were contrasted and no significant differences were found with respect to the incidence of hemorrhage, uterine atony, hysterectomy, or the requirement of transfusions. Neonatal outcome was also comparable for both groups. On the basis of our prospective experience, it appears that the use of oxytocin, when carefully monitored, is a safe and reasonable consideration in the patient undergoing a trial of labor.

Adult↗
PubMed1991

Multicenter randomized clinical trial of home uterine activity monitoring for detection of preterm labor.

Home uterine activity monitoring has been described as an effective means of detecting uterine contractions, but controversy exists whether it is home uterine activity monitoring or increased nursing support in conjunction with it that contributes to earlier detection of preterm labor. In this study 377 women at risk for preterm labor from three centers were prospectively, randomly assigned to high-risk prenatal care alone (not monitored) or to the same care with twice-daily home uterine activity monitoring without increased nursing support (monitored). The two groups were medically and demographically similar at entry into the study. Routine visits, nonroutine visits, and gestational age at diagnosis of preterm labor were similar in both groups. Preterm labor occurred in 41 of 198 monitored and 39 of 179 not monitored patients. Mean cervical dilatation was 1.4 cm in 41 monitored compared with 2.5 cm for 37 not monitored (p = 0.0006); 73.1% of monitored and 27.5% of not monitored had preterm labor detected before 2 cm dilatation (p = 0.00009). Neonatal outcome of singleton pregnancies showed greater birth weight, fewer days in the neonatal intensive care unit, and fewer babies requiring oxygen therapy and mechanical ventilation in the monitored group. The better outcomes are probably due to the increased likelihood of diagnosis of preterm labor before advanced cervical dilatation with home uterine activity monitoring, thus providing the clinician with a better chance to initiate tocolytic therapy directed at improving pregnancy outcome.

Birth Weight↗
PubMed1992

Prostaglandin E2 for induction of labor in patients with premature rupture of membranes at term.

OBJECTIVE: A prospective study comparing three management schemes for patients at term with premature rupture of membranes was performed. STUDY DESIGN: One hundred forty patients were randomized to one of three study groups: prostaglandin E2, placebo, or oxytocin. Patients randomized to prostaglandin E2 and placebo received vaginal suppositories containing 3 mg prostaglandin E2 or glycerin only, respectively; suppositories were administered in a double-blind fashion, on one or two occasions, 6 hours apart. Oxytocin was given only if labor was not established after 12 hours or to augment inadequate labor. In patients randomized to oxytocin labor was induced with intravenous oxytocin. The time interval to delivery, delivery outcome, and complications were analyzed. RESULTS: Patients receiving prostaglandin E2 were more likely to be in labor after one suppository and to be delivered without the addition of oxytocin when compared with placebo. The time interval to delivery was shorter with prostaglandin E2 and oxytocin induction versus placebo ("expectant management"). The incidence of maternal infection was lowest in patients with labor induced by prostaglandin E2. Although the overall cesarean section rate was low, there was a trend toward a lower rate with prostaglandin E2 induction. No adverse effects were observed with prostaglandin E2. CONCLUSION: Prostaglandin E2 can be used successfully to induce labor after premature rupture of membranes at term with greater ease of administration when compared with oxytocin.

Cesarean Section↗
PubMed2005

Cesarean delivery and respiratory distress syndrome: does labor make a difference?

OBJECTIVE: The purpose of this study was to determine if cesarean delivery is a risk factor for respiratory distress syndrome (RDS) and if this risk is modified by labor before cesarean. STUDY DESIGN: This population-based case-control study compared 4778 cases of RDS to 5 times as many controls. RESULTS: Unadjusted, cesarean delivery was associated with RDS, odds ratio (OR) 3.5 (95% CI 3.2-3.8). After controlling for potential confounding variables, cesarean remained an independent risk factor, OR 2.3 (95% CI 2.1-2.6). Labor modified this risk significantly (P = .02)--with labor, cesarean delivery had an OR of 1.9 (95% CI 2.2-2.9), without labor, the OR was 2.6 (95% CI 1.3-2.8). CONCLUSION: Cesarean delivery was an independent risk factor for RDS. The risk was reduced with labor before cesarean, but still elevated. This supports the importance of being certain of fetal lung maturity before cesarean delivery, particularly when done before labor.

Case-Control Studies↗