Maternal Temperature Research Articles

Foley Bulb Added to an Oral Misoprostol Induction Protocol: A Cluster Randomized Trial.

To evaluate whether the induction of labor in term gravid women with cervical dilation 2 cm or less and intact membranes by using oral misoprostol preceded by transcervical Foley bulb placement results in a significantly increased vaginal delivery rate compared with the use of oral misoprostol alone. We randomized the induction method by week of admission to labor and delivery, with each week group described as a cluster in a block randomized design. Women with gestational age of 37 weeks or greater, cervical dilation 2 cm or less, intact membranes, and indication for labor induction were included. Study arms were either 100 micrograms of oral misoprostol after transcervical Foley bulb placement or 100 micrograms of oral misoprostol alone. The primary outcome was vaginal delivery with the first induction attempt. Secondary outcomes included time to delivery, clinical chorioamnionitis (maternal temperature of 38°C or greater during labor with or without fundal tenderness, without other identified cause), cesarean delivery indication, and adverse outcomes. We estimated that a sample size of 1,077 per arm was needed to detect a 5% increase in vaginal delivery rate with a type I error of 5% and power of 80%, accounting for interim analysis and cluster size of 30 inductions per week. This was a pragmatic trial, and analysis was by intention-to-treat. From January 1, 2018, to May 13, 2019, 1,117 women (34 clusters) were assigned to oral misoprostol plus Foley and 1,110 women (34 clusters) to oral misoprostol alone. Demographic characteristics were similar. Vaginal delivery at the first induction occurred in 78% of the misoprostol plus Foley arm and in 77% of the misoprostol arm (relative risk [RR] 1.00; 95% CI 0.96-1.05; adjusted relative risk [aRR], 1.00; 95% CI 0.95-1.05). Clinical chorioamnionitis occurred in 18% of the misoprostol plus Foley arm and in 14% of the misoprostol arm (RR 1.30; 95% CI 1.07-1.58; aRR 1.30; 95% CI 1.08-1.56). There were no differences in neonatal outcomes. Induction of labor in gravid women at term with intact membranes by using oral misoprostol plus Foley bulb did not result in a higher vaginal delivery rate, but it did result in more clinical chorioamnionitis compared with the use of oral misoprostol alone. ClinicalTrials.gov, NCT03407625.

Transabdominal amniocentesis in expectant management of preterm premature rupture of membranes: A single center prospective study.

The aim of this study was to evaluate the role of IL-6 point-of-care test in amniotic fluid obtained from serial amniocentesis in expectantly managed women with PPROM between 24 and 34 weeks of gestation. We conducted a prospective observational cohort study which included 62 pregnant women with PPROM in gestational weeks between 22+0 and 34+0. Women aged >18 years were eligible if they presented with PPROM and a singleton pregnancy. Only women who delivered at >24.0 weeks were included in the study. In all women, the maternal blood sampling and a transabdominal amniocentesis were performed at the time of admission prior to the administration of corticosteroids, antibiotics, or tocolytics, to rule out signs of chorioamnionitis. Maternal temperature, maternal serum C-reactive protein (CRP) and white blood cell (WBC) counts were assayed every subsequent day until delivery. Amniotic fluid was used for the clinical assessment (IL-6 point-of-care test, identification of microorganisms in the amniotic fluid. After one week of expectant management of PPROM, second amniocentesis with amniotic fluid sampling was performed in patients who did not deliver. For all newborns, medical records regarding neonatal morbidity and mortality were reviewed. In total, 62 women aged 19 to 41 years were recruited in the study. The mean gestational age at the time of PPROM was 31+0, the mean gestational age at labor was 32+1, and the median time from PPROM to childbirth was 112 h. IL-6 point-of-care test values above 1,000 pg/mL (positive Il-6 AMC) were found in 12 women (19.4%) with median interval from PPROM to childbirth 56 h (min-max: 6.4-288). IL-6 point-of-care test values below 1,000 pg/mL (negative Il-6 AMC) were found in 51 women (81.0%). The neonatal mortality rate was 1.9% and was associated with prematurity. The major clinical finding of our study is that serial transabdominal amniocentesis with Il-6 point-of-care test helps to identify a high inflammatory status in amniotic fluid in women with PPROM. Subsequent expectant management of women with PPROM does not lead to worsening of short-term neonatal outcomes.

Maternal, Placental, and Fetal Responses to Intermittent Heat Exposure During Late Gestation in Mice.

Physiological adaptations during heat exposure are critical in pregnancy. Maternal thermoregulation has to accommodate the increased metabolic load of the developing fetus. Here, we assess the consequences of intermittent heat exposure, as occurs in heat waves, for maternal adaptations during pregnancy, and chronic feto-placental outcomes. Following timed mating, C57BL/6J mice were allocated to either standard animal housing temperature conditions (SH) or housing at a temperature within the thermoneutral zone (TNZ). A subset of the TNZ group was exposed to 37°C for 8h a day from E15.5 to E17.5 to simulate a heat wave (HW). Maternal weight gain, food intake, rectal temperature, and nesting behaviors were measured across gestation. Fetal and placental tissues were collected at E18.5. With heat exposure, maternal rectal temperature increased while food intake and nest complexity decreased. Maternal daily weight gain initially decreased due to heat exposure, but on the last day of exposure, it was comparable to the other experimental groups. These maternal responses during heat exposure impacted on the fetus, with restrictions in placental and fetal development evident just before birth. Thus, the vascular portion of the placenta, and the relative fetal head size, was smaller. Furthermore, SH and TNZ animals demonstrated distinct differences in food intake and nesting behavior during pregnancy, reinforcing the need for caution in extrapolating from animal models to humans when housing occurs outside of thermoneutral zone conditions. This study highlights the direct effects of temperature conditions on health in pregnancy and provides a foundation for future studies to investigate fetal health consequences that are associated with intermittent heat exposure.

Hypertension Editors' Picks: Air Pollution.

Hypertension Editors' Picks: Air Pollution.

Update on the gestational effects of maternal hyperthermia.

I plan to review the types of defects caused by gestational hyperthermia. Hyperthermia-induced malformations in animals and humans involve many organs and structures, particularly the central nervous system, as well as other defects. The type of defect is related to the timing of the hyperthermic insult, and the underlying mechanisms include cell death, membrane disruption, vascular disruption, and placental infarction. Review of recent epidemiologic studies (2005-2020) has confirmed an association between gestational hyperthermia and birth defects. There are strong associations between neural tube defects and maternal fever, and other studies have demonstrated associations between first trimester hyperthermia and an increased risk for cardiovascular defects, oral clefts, isolated congenital ear defects, cataracts, hypospadias, renal anomalies, possibly anorectal malformations, and congenital anomalies in general, suggesting that this association between maternal hyperthermia and birth defects in humans is causal. The first prospective evaluation of maternal fever was reported in 1998, and this study confirmed findings from previous case-control studies and case series regarding the magnitude and duration of elevated maternal body temperature in relation to an increased risk for neural tube defects as well as a specific pattern of malformation. The consistency of findings across these different study designs supports the causal nature of the relationship between maternal fever and specific birth defects. This review summarizes the recent human evidence documenting the gestational effects of maternal hyperthermia.

Chorioamnionitis versus intraamniotic infection among preterm deliveries—is postpartum infectious morbidity different?

Chorioamnionitis can have a highly variable definition with substantial maternal and fetal morbidity, with higher frequencies in preterm births. With the recently updated intraamniotic infection diagnostic criteria by the American College of Obstetricians and Gynecologists, fewer women experiencing preterm delivery may qualify for intrapartum antibiotic treatment, potentially resulting in higher postpartum infectious morbidity. This study aimed to estimate whether the proportion of women delivering preterm who develop postpartum endometritis differs between subjects diagnosed as having clinical chorioamnionitis and those meeting the American College of Obstetricians and Gynecologists' criteria for intraamniotic infection. Secondary analysis was conducted using a randomized controlled trial of antenatal magnesium sulfate for the prevention of cerebral palsy. Subjects were included if they had a clinical diagnosis of chorioamnionitis and maternal temperature of ≥37.8°C and excluded if maternal temperature data were missing. The exposure group included women who met the criteria for intraamniotic infection, defined as a single maternal temperature of ≥39.0°C or maternal temperature of 38.0°C to 38.9°C plus 1 additional clinical risk factor (leukocytosis, purulent cervical drainage, or fetal tachycardia). The primary outcome was postpartum endometritis. The odds of postpartum endometritis were compared between women with intraamniotic infection and women with clinical chorioamnionitis, after adjusting for potential confounders using multivariate logistic regression. Of the original study population, 258 of 2241 (11.8%) subjects met the criteria for chorioamnionitis. Nearly all subjects (98.5%) received antibiotic treatment between randomization and delivery. A total of 144 subjects (55.8%) met the criteria for intraamniotic infection, whereas 114 (44%) only met the criteria for clinical chorioamnionitis. A total of 40 women (15.5%) experienced postpartum endometritis. Women with intraamniotic infection had higher parity (P=.02) and higher maximum maternal temperature (P<.001) and were more likely to have received antibiotic treatment (P=.04). Postpartum endometritis rates were similar between subjects with chorioamnionitis and intraamniotic infection (12% vs 18%; P=.50). After adjustment for potential confounders, the odds of developing postpartum endometritis did not differ between subjects who met the criteria for intraamniotic infection and those who did not (adjusted odds ratio, 1.28; 95% confidence interval, 0.62-2.62). Patients delivering preterm who receive a diagnosis of clinical chorioamnionitis in the intrapartum period seem to have similar odds of developing postpartum endometritis as those meeting the American College of Obstetricians and Gynecologists' criteria for intraamniotic infection, suggesting that this group remains at a high risk for postpartum infectious complications.

Fetal Bradycardia in Response to Maternal Hypothermia [15O

INTRODUCTION: Fetal bradycardia, especially if it develops abruptly in the setting of a normal fetal heart (FHR) tracing, is most often associated with fetal compromise. The differential diagnosis may include numerous maternal, placental, and fetal conditions that would prompt emergent delivery. These causes are usually associated with an absence of FHR accelerations and decreased or absent variability. On the other end of the spectrum, fetal tachycardia also has numerous causes, one of which is maternal fever (or hyperthermia). Therefore, it is plausible that the opposite effect of a low maternal temperature or hypothermia might produce fetal bradycardia. The purpose of this case series is to demonstrate this finding. METHODS: 6 cases of fetal bradycardia associated with maternal hypothermia were collected. Data collection included gestational age at presentation, maternal medical condition, maternal temperature, FHR baseline, presence and/or absence of FHR variability and accelerations, and pregnancy outcome. RESULTS: All 6 cases demonstrated FHR baselines in the 80–90s in the setting of maternal hypothermia. Maternal temperatures ranged from 92.1–96.9 0F. All had moderate variability with the presence of accelerations. All FHR baselines returned to normal with correction of maternal temperature. No adverse outcomes were seen in the 6 neonates post-delivery. CONCLUSION: These cases demonstrated fetal bradycardia can be seen in the presence of maternal hypothermia. The appearance of the FHR tracing is reassuring, except for the baseline. Therefore, emergent delivery is not indicated. The FHR baseline returns to normal with correction of maternal temperature. The overall clinical picture should be taken into consideration before proceeding with delivery.

Programmed Intermittent Epidural Bolus at Different Intervals Combined with Patient-controlled Epidural Analgesia on Body Temperature during Labour Analgesia.

Descriptive study. The First Affiliated Hospital of Shaoyang University, China, from September 2018 to February 2020. One hundred and seventy primiparous women, who had vaginal delivery and required labour analgesia, were randomly divided into Groups A and B (n=85 for each group). In both groups, PIEB plus PCEA mode was applied when cervical dilatation reached 2-3 cm. The interval was 30 minutes with a pulse dose of 5 mL in Group A; and 60 minutes with a pulse dose of 10 mL in Group B. Indicators related to body temperature and serum markers were compared in both the groups. Maternal temperature in Group A was higher than that in Group B at the time of cervix being completely dilated, and 2 hours after delivery (both p <0.001). incidence of intrapartum fever in Group A was higher than that in Group B (p = 0.036). Epidural analgesic dosage, VAS score, serum CRP, TNF-α, and IL-6 levels in Group A were higher than those in Group B at two hours after delivery (all p <0.001). PIEB plus PCEA mode at regular intervals of 60 minutes can reduce epidural analgesic dosage and incidence of intrapartum fever during delivery, thus exerting better analgesic effects. Key Words: Programmed intermittent epidural bolus (PIEB), Patient-controlled epidural analgesia (PCEA), Delivery, Analgesia, Parturient, Body temperature.

Clinical Predictors of Histologic Chorioamnionitis at Term [06N

INTRODUCTION: The objective of this study was to determine the diagnostic criteria for clinical chorioamnionitis (CC) that best predict histologic chorioamnionitis (HC). METHODS: This is an IRB-approved retrospective cohort study of women diagnosed with CC over a 5-year period. Inclusion criteria were: gestational age 37 to 42 weeks, diagnosis of CC as determined and documented by the provider, and available placental pathology records. CC diagnostic criteria (maternal temperature, maternal or fetal tachycardia, leukocytosis, fundal tenderness, and purulent amniotic fluid) were compared between those with and without HC. RESULTS: 223 women met inclusion criteria; 159 (71.3%) had HC. Prostaglandin use, diabetes, epidural use, and duration from initiation of antibiotics to delivery were similar. Mean maximum body temperature and presence of other diagnostic criteria were similar between the groups. Those with HC were more likely to have a peak white blood cell count greater than or equal to 25.0x10^9cells/L (13.2 vs 3.1%, P=.03). Twenty-one (13.2%) women in the HC group and 12 (18.8%) in the normal pathology group had no documented fever despite a diagnosis of CC. Of the women without a fever, 64% had HC. CONCLUSION: Normal placental pathology was found in a large proportion of women with CC. Although none of the assessed clinical findings predicted HC, a significant leukocytosis was more frequent in women with HC. For women diagnosed with CC without fever, the majority had findings of HC. This study highlights the challenge of diagnosing CC. Providers should consider the diagnosis of CC in the absence of fever when other clinical criteria are present.

Improving intraoperative temperature management in elective repeat cesarean deliveries: a retrospective observational cohort study

BackgroundInadvertent perioperative hypothermia (< 36 °C) occurs frequently during elective cesarean delivery and most institutions do employ perioperative active warming. The purpose of this retrospective observational cohort study was to determine if the addition of preoperative forced air warming in conjunction with intraoperative underbody forced air warming improved core temperature and reducing inadvertent perioperative hypothermia during elective repeat elective cesarean delivery with neuraxial anesthesia.MethodsWe evaluated the addition of perioperative active warming to standard passive warming methods (preheated intravenous/irrigation fluids and cotton blankets) in 120 parturients scheduled for repeat elective cesarean delivery (passive warming, n = 60 vs. active + passive warming, n = 60) in a retrospective observational cohort study. The primary outcomes of interest were core temperature at the end of the procedure and a decrease in inadvertent perioperative hypothermia (< 36 °C). Secondary outcomes were surgical site infections and adverse markers of neonatal outcome.ResultsThe mean temperature at the end of surgery after instituting the active warming protocol was 36.0 ± 0.5 °C (mean ± SD, 95% CI 35.9–36.1) vs. 35.4 ± 0.5 °C (mean ± SD, 95% CI 35.3–35.5) compared to passive warming techniques (p < 0.001) and the incidence of inadvertent perioperative hypothermia at the end of the procedure was less in the active warming group - 68% versus 92% in the control group (p < 0.001). There was no difference in surgical site infections or neonatal outcomes.ConclusionsPerioperative active warming in combination with passive warming techniques was associated with a higher maternal temperature and lower incidence of inadvertent perioperative hypothermia with no detectable differences in surgical site infections or indicators of adverse neonatal outcomes.

Body temperature at nursery admission in a cohort of healthy newborn infants: results from an observational cross-sectional study

BackgroundExposure to hypothermia is somehow unavoidable when a baby comes to life. This is the reason why any possible effort should be made by every caregiver involved during birth, from labour to transfer into the maternity ward, to reduce it. Hypothermia has widely shown to be related to several neonatal problems, and the risks are more relevant when the babies are born prematurely.MethodAn observational study was conducted in April 2016 to assess the current practises to avoid hypothermia at birth in 20 Italian neonatal units. Each unit introduced local improvements in clinical practice and the same observational study was repeated 1 year later.ResultsA total of 4722 babies were analysed. An overall increase in adherence to local and international recommendations emerged from our study. Significant differences between 2016 and 2017 were found in regard to neonatal temperature at nursery entry (36.3 °C vs 36.5 °C, respectively, p < 0.0001), delayed cord clamping practice > 60″ (48.1% vs 68.1%, respectively, p < 0.0001) and skin-to-skin practice > 60′ (56.3% vs 60.9, respectively, p = 0.03). Statistical correlations with the risk of hypothermia were found for delivery room (OR 0.88 (CI 95%0.83–0.94), p < 0.0001) and maternal temperature (OR 0.57 (CI 95% 0.48–0.67), p < 0.0001).ConclusionPeriodical assessment of the delivery room practice has shown to be effective in improving adherence to the international recommendations. Relationship between neonatal hypothermia and several other variables including the delivery room and mother temperature underlines how neonatal thermoregulation starts immediately after birth. Hence, a multi-disciplinary approach is needed to provide the optimal environment for a safe birth.

Associations of maternal ambient temperature exposures during pregnancy with the placental weight, volume and PFR: A birth cohort study in Guangzhou, China

BackgroundThe placenta performs crucial functions to ensure normal fetal development. Experimental studies have indicated associations between exposure to elevated temperatures during pregnancy and reduction in placental weight and volume. However, epidemiological studies in humans are lacking. ObjectiveTo estimate the associations between prenatal exposure to ambient temperature with placental weight, volume, and the placental weight to birth weight ratio (PFR). MethodsWe conducted a prospective birth cohort study using the Prenatal Environment and Offspring Health Cohort (PEOH Cohort) beginning in 2016 in Guangzhou, China. Women in early pregnancy were recruited and followed up during their hospitalization for childbirth. An inverse distance-weighted method was employed to estimate the average temperature exposure of every 4 weeks as well as the trimester-specific average temperature exposure at the individual’s residential address. A generalized linear model was applied to estimate the effects of temperature exposure during pregnancy on the placental weight, volume, and PFR. ResultsA total of 4051 pregnant women were enrolled. Compared with the reference temperature of 20 °C, maternal exposure to 29 °C (95th centile) during late pregnancy was associated with an average of −6.03 g (95% confidence interval [CI]: −11.28 g, −0.78 g) in placental weight, −16.15 cm3 (95% CI: −26.24 cm3, −6.07 cm3) in placental volume, and 0.26 (95% CI: 0.07, 0.45) in PFR. The peak effects of high temperatures on placental weight, volume, and PFR were found from 29 to 32 weeks (β = –3.79 g, 95% CI: −8.39 g, 0.82 g), 37 to 40 weeks (β = −19.34 cm3, 95% CI: −30.99 cm3, −7.69 cm3), and 25 to 28 weeks (β = 0.35, 95% CI: 0.04, 0.66), respectively. ConclusionsMaternal exposure to elevated temperatures was associated with a decrease in placental weight and volume and an increase in PFR. The associations were stronger when exposures occurred during late pregnancy.

A protocol for an observational cohort study of heat strain and its effect on fetal wellbeing in pregnant farmers in The Gambia.

Introduction: Climate change predictions indicate that global temperatures are likely to exceed those seen in the last 200,000 years, rising by around 4°C above pre-industrial levels by 2100 (without effective mitigation of current emission rates). In regions of the world set to experience extreme temperatures, women often work outside in agriculture even during pregnancy. The implications of heat strain in pregnancy on maternal health and pregnancy outcome are not well understood. This protocol describes a study to assess the physiological response of pregnant women to environmental heat stress and the immediate effect this has on fetal wellbeing. Methods and analysis: The study will be performed in West Kiang district, The Gambia; a semi-arid zone in West Africa with daily maximum temperatures ranging from approximately 32 to 40°C. We will recruit 125 pregnant women of all ages who perform agricultural work during their pregnancy. Participants will be followed every two months until delivery. At each study visit fetal growth will be measured by ultrasound scan. During the course of their working day we will take the following measurements: continuous maternal physiological measurements (heart rate, respiratory rate, chest skin temperature and tri-axis accelerometer data); intermittent maternal tympanic core temperature, four point skin temperature, blood pressure; intermittent fetal heart rate and, if eligible, umbilical artery doppler; intermittent environmental measurements of air temperature, humidity, solar radiation and wind speed. Venous blood and urine will be collected at beginning and end of day for biomarkers of heat strain or fetal distress and hydration status.

A protocol for an observational cohort study of heat strain and its effect on fetal wellbeing in pregnant farmers in The Gambia

Introduction: Climate change predictions indicate that global temperatures are likely to exceed those seen in the last 200,000 years, rising by around 4°C above pre-industrial levels by 2100 (without effective mitigation of current emission rates). In regions of the world set to experience extreme temperatures, women often work outside in agriculture even during pregnancy. The implications of heat strain in pregnancy on maternal health and pregnancy outcome are not well understood. This protocol describes a study to assess the physiological response of pregnant women to environmental heat stress and the immediate effect this has on fetal wellbeing. Methods and analysis: The study will be performed in West Kiang district, The Gambia; a semi-arid zone in West Africa with daily maximum temperatures ranging from approximately 32 to 40°C. We will recruit 125 pregnant women of all ages who perform agricultural work during their pregnancy. Participants will be followed every two months until delivery. At each study visit fetal growth will be measured by ultrasound scan. During the course of their working day we will take the following measurements: continuous maternal physiological measurements (heart rate, respiratory rate, chest skin temperature and tri-axis accelerometer data); intermittent maternal tympanic core temperature, four point skin temperature, blood pressure; intermittent fetal heart rate and, if eligible, umbilical artery doppler; intermittent environmental measurements of air temperature, humidity, solar radiation and wind speed. Venous blood and urine will be collected at beginning and end of day for biomarkers of heat strain or fetal distress and hydration status.

Out Come of Expectant Management and Induction of Labour with Premature Rupture of Membrane in Term Pregnancy

Introduction: Overall, at least 50% of mothers with PROM near term deliver within 48 hours. The latency period is in general inversely related to the gestational age at the time of PROM. At term, labor is desirable since infections become more likely with more prolong intervals between rupture and delivery. Neonatal complications and perinatal mortality and morbidity also associated with PROM.&#x0D; Material and methods: This randomized clinical trial study was carried out in the Department of Obstetrics and Gynecology Sir Salimuilah Medical College and Mitford Hospital Dhaka, during the period of January 2008 to September 2008. A total of 100 patients with term pregnancy had single fetus and cephalic presentation with PROM were enrolled in this study. After taking informed consent she was randomized in one of the two either groups according to the results of lottery. Fifty in Group I- Termination of the pregnancy (intervention group) by induction of labour and another 50 were in Group II- Expectant management for spontaneous delivery (expectant group). Randomization was 1:1 for intervention and expectant management. Proper history including demographic, past obstetric and medical history was taken, maternal temperature and Fetal heart rate was recorded. Antibiotics were given to all PROM women. The women of intervention group were induced by following ways -Women with riped cervix with oxytocin infusion and with unripe cervix, first underwent ripening by misoprostol followed by oxytocin infusion. Data was collected by standard questionnaire; results were compiled and relevant statistical calculation was done using computer-based software (SPSS).&#x0D; Results: The mean age was 20-24 years were predominant in both groups. Low income patients were more common in both groups. Primigravida were predominant in both groups. The mean gestation age was almost similar in both groups, no significant (p&gt;0.05) difference was found between two groups. Majority (80%) patients had time interval 1 to 12 hours between rupture membrane and onset of labour pain in group I. On the other hand 80% patients in group II had 12 to 24 hours time interval for onset of labour pain after rupture membrane.Normal vaginal delivery was higher in group I, whereas caesarean section (LSCS) was higher group II. No statistically significant (p&gt;0.05) difference was found between two groups.Duration of time interval between on set of labour pain to delivery was &lt;12 hours in group I 88.0% patients and 96.0% in group II respectively. No statistically significant (p&gt;0.05) difference was found between two groups.Hundred percent cases was live birth in both groups. Neonatal infection and death were significantly (p&lt;0.05) higher in group II. Puerperal sepsis was significantly (p&lt;0.05) higher in group II.The mean duration of hospital stay was 4.1±2.2 and 5.1±3.7 days in group I and group II respectively but this was not significant (p&gt;0.05).&#x0D; Conclusion: In the present study there was no statistical difference in the mode of delivery and time interval between onset of labour pain and delivery in two groups though maternal complications, neonatal infection and perinatal death was higher where expectant management was followed.&#x0D; Anwer Khan Modern Medical College Journal Vol. 11, No. 1: Jan 2020, P 59-65

Effects of combined warmed preoperative forced-air and warmed perioperative intravenous fluids on maternal temperature during cesarean section: a prospective, randomized, controlled clinical trial

BackgroundPreventing the frequent perioperative hypothermia incidents that occur during elective caesarean deliveries would be beneficial. This trial aimed at evaluating the effect of preoperative forced-air warming alongside perioperative intravenous fluid warming in women undergoing cesarean sections under spinal anesthesia.MethodsWe randomly allocated 135 women undergoing elective cesarean deliveries to either the intervention group (preoperative forced-air and intravenous fluid warming, n = 69) or the control group (no active warming, n = 66). The primary outcome measure was the core temperature change between groups from baseline to the end of the surgical procedure. Secondary outcomes included thermal comfort scores, the incidences of shivering and hypothermia (< 36 °C), the core temperature on arrival at the post-anesthesia care unit, neonatal axillary temperature at birth, and Apgar scores.ResultsTwo-way repeated measures ANOVA revealed significantly different core temperature changes (from the pre-spinal temperature to that at the end of the procedure) between groups (F = 13.022, P < 0.001). The thermal comfort scores were also higher in the intervention group than in the control group (F = 9.847, P = 0.002). The overall incidence of perioperative hypothermia was significantly lower in the intervention group than in the control group (20.6% vs. 51.6%, P < 0.0001).ConclusionsWarming preoperative forced-air and perioperative intravenous fluids may prevent maternal hypothermia, reduce maternal shivering, and improve maternal thermal comfort for patients undergoing cesarean sections under spinal anesthesia.Trial registrationThe study was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR1800019117) on October26, 2018.

A protocol for an observational cohort study of heat strain and its effect on fetal wellbeing in pregnant farmers in The Gambia

Introduction: Climate change predictions indicate that global temperatures are likely to exceed those seen in the last 200,000 years, rising by around 4°C above pre-industrial levels by 2100 (without effective mitigation of current emission rates). In regions of the world set to experience extreme temperatures, women often work outside in agriculture even during pregnancy. The implications of heat strain in pregnancy on maternal health and pregnancy outcome are not well understood. This protocol describes a study to assess the physiological response of pregnant women to environmental heat stress and the immediate effect this has on fetal wellbeing. Methods and analysis: The study will be performed in West Kiang district, The Gambia; a semi-arid zone in West Africa with daily maximum temperatures ranging from approximately 32 to 40°C. We will recruit 125 pregnant women of all ages who perform agricultural work during their pregnancy. Participants will be followed every two months until delivery. At each study visit fetal growth will be measured by ultrasound scan. During the course of their working day we will take the following measurements: continuous maternal physiological measurements (heart rate, respiratory rate, chest skin temperature and tri-axis accelerometer data); intermittent maternal tympanic core temperature, four point skin temperature, blood pressure; intermittent fetal heart rate and, if eligible, umbilical artery doppler; intermittent environmental measurements of air temperature, humidity, solar radiation and wind speed. Venous blood and urine will be collected at beginning and end of day for biomarkers of heat strain or fetal distress and hydration status.

Associations of maternal ambient temperature exposures during pregnancy with the risk of preterm birth and the effect modification of birth order during the new baby boom: A birth cohort study in Guangzhou, China.

Maternal exposures to ambient temperatures during pregnancy may increase the preterm birth (PTB) risk; however, which periods have stronger effects remain controversial. The effects of temperature exposure on PTB in first- and second-born neonate groups may be different during the new baby boom that has followed the Two-child Policy in China. We examined a birth cohort of 4928 pregnant women beginning in 2016 in Guangzhou, China. An inverse distance weighted method was used to estimate the temperature exposure at each individual residential address. A distribution lag non-linear model incorporating a Cox proportional hazard model was employed to estimate the effects of temperature exposure on PTB and test the effects modification of birth order related to the new baby boom. A total of 4101 pregnant women were included, of which 234 (5.7%) experienced PTB. Compared with the mean temperature (23.0°C), we found a significantly higher risks of PTB associated with high temperatures (i.e, 30°C [95th centile]) from the 4th to 8th, and 22nd to 27th gestational weeks. A peak effect was found during the 6th week (HR=1.79, 95% CI: 1.26, 2.54) and 24th week (HR=1.83, 95% CI: 1.27, 2.62). The risks of PTB were reduced for low temperatures (i.e. 14°C [5th centile] versus 23.0°C) from the 2nd to 10th and 20th to 26th gestational weeks, and the negative peak effect was found during the 4th week (HR=0.43, 95% CI: 0.26, 0.72) and 23rd week (HR=0.59, 95% CI: 0.43, 0.83). Stratification analyses showed that significant effects of 30°C versus 23°C on PTB were observed during the 4th to 8th weeks in the second-born neonate, and the peak effect was found in the 6th week (HR=2.13, 95% CI: 1.31, 3.47). However, we did not find significant effects of 30°C during the same weeks in the first-born neonate group. Maternal exposures to higher temperatures during pregnancy may increase the risk of PTB, and lower temperatures may decrease the risk of PTB. Stronger effects of temperature exposures during the first trimester on PTB risk were found among the second-born neonates than among the first-born neonates.

Effects of Labor Epidural Analgesia on Short Term Neonatal Morbidity.

BackgroundEpidural Analgesia (EA) is the most effective and most commonly used method for pain relief during labor. Some researchers have observed an association between EA and increased neonatal morbidity. But this observation was not consistent in many other studies.ObjectivesThe primary objective of the study was to examine whether exposure to epidural analgesia increased the risk of NICU admission. The secondary objectives included the risks of clinical chorioamnionitis, instrumental delivery, neonatal depression, respiratory distress, birth trauma, and neonatal seizure during the first 24 hours of life.MethodsThis was a retrospective cohort study involving 2360 low-risk nulliparous women who delivered at AWH, Qatar, during the two years between January 2016 December and 2017. Short-term neonatal outcomes of the mothers who received EA in active labor were compared with a similar population who did not receive EA. As secondary objectives, labor parameters like maternal temperature elevation, duration of the second stage of labor, and instrumental delivery were compared.ResultsSignificantly higher numbers of neonates were admitted to the NICU from the EA group (P<0.001, OR 1.89, 95% CI 1.45 to 2.46). They were more likely to have respiratory distress (P=0.01, OR 1.49, 95% CI 1.07 to 2.07), birth injuries (P=0.02, OR =1.71, 95% CI 1.06 to 2.74), admission temperature>37.5 °C (P=0.04, OR 3.40, 95% CI 1.00 to 11.49), need for oxygen on the first day (P=0.04, OR 1.44, 95% CI 1.01 to 2.07) and receive antibiotics (P<0.001, OR 2.06,95% CI 1.47 to 2.79). There was no difference in the Apgar score at 1 minute (P=0.12), need of resuscitation at birth (P=0.05), neonatal white cell count (P=0.34), platelet count (P=0.38) and C reactive protein (P=0.84). Mothers who received EA had a lengthier second stage (P<0.001), temperature elevation >37.5°C (P<0.001, OR 7.40, 95% CI 3.93 to 13.69) and instrumental delivery (P<0.001, OR 2.13, 95% CI 1.69 to 2.68).ConclusionEA increases NICU admission, antibiotic exposure, neonatal birth injuries, need for positive pressure ventilation at birth, and respiratory distress in the first 24 hours of life. Mothers on epidural analgesia have prolonged second stage of labor, a higher rate of instrumental delivery, meconium-stained amniotic fluid, fetal distress, and temperature elevation.

Wintertime Wood Smoke, Traffic Particle Pollution, and Preeclampsia.

Previous studies have reported associations between ambient fine particle concentrations and preeclampsia; however, the impact of particulate pollution on early- and late-onset preeclampsia is understudied. Furthermore, few studies have examined the association between source-specific particles such as markers of traffic pollution or wood combustion on adverse pregnancy outcomes. Electronic medical records and birth certificate data were linked with land-use regression models in Monroe County, New York for 2009 to 2013 to predict monthly pollutant concentrations for each pregnancy until the date of clinical diagnosis during winter (November-April) for 16 116 births. Up to 30% of ambient wintertime fine particle concentrations in Monroe County, New York is from wood combustion. Multivariable logistic regression was used to separately estimate the odds of preeclampsia (all, early-, and late-onset) associated with each interquartile range increase in fine particles, traffic pollution, and woodsmoke concentrations during each gestational month, adjusting for maternal characteristics, birth hospital, temperature, and relative humidity. Each 3.64 µg/m3 increase in fine particle concentration was associated with an increased odds of early-onset preeclampsia during the first (odds ratio, 1.35 [95% CI, 1.08-1.68]), second (odds ratio, 1.51 [95% CI, 1.23-1.86]), and third (odds ratio, 1.25 [95% CI, 1.06-1.46]) gestational months. Increases in traffic pollution and woodsmoke during the first gestational month were also associated with increased odds of early-onset preeclampsia. Increased odds of late-onset preeclampsia were not observed. Our findings suggest that exposure to wintertime particulate pollution may have the greatest effect on maternal cardiovascular health during early pregnancy.