Background: The aims of this study were(a) to ascertain age-related changes in the reference values in hematological and serum biochemical examinations of beagles,and(b) to clarify the changes in these findings, inclu...Background: The aims of this study were(a) to ascertain age-related changes in the reference values in hematological and serum biochemical examinations of beagles,and(b) to clarify the changes in these findings, including acute phase proteins and oxidative stress, throughout pregnancy and after parturition.Methods: Clinicopathological parameters were measured in young beagles at 6, 9 and 12 months and in adult beagles aged from 24 to 60 months. Likewise, pregnant beagles were investigated throughout the pregnancy and after parturition.Results: Apparent age-related changes were found in erythrocytic parameters during the growth and development of beagles. Most of the parameters(total protein,albumin, blood urea nitrogen, creatinine, urate, alkaline phosphatase(ALP) and creatine kinase(CK) exhibited age-dependent transitions. White cell count significantly increased after 30 days of pregnancy. The values of erythrocytic parameters moderately decreased during the second half of the pregnancy. Triglycerides, total cholesterol, free cholesterol and phospholipid concentrations increased in the mid- and late stages of pregnancy. ALP, lactate dehydrogenase, CK and cholinesterase activities markedly increased during pregnancy and/or after parturition. C-reactive protein(CRP) concentrations gradually increased and reached a maximum after 30-40 days of pregnancy. Serum amyloid A(SAA) levels markedly increased at 30 days of pregnancy before subsiding, and then increased again 3 days after parturition. Reactive oxygen metabolites(d-ROMs) showed significant increases after 30 and 40 days of pregnancy.Conclusions: Reference values for hematological and serum biochemical examinations should be used for health evaluation of dogs, taking sex, age and the stage of pregnancy into consideration. Measurements of CRP, SAA and d-ROM levels are also useful for assessing maternal conditions in mid-pregnancy.展开更多
Increased predation losses in beef cattle in the Northern Rocky Mountains raise the importance of research concerning maternal behavior around the time of parturition. Separation behavior of multiparous cows at partur...Increased predation losses in beef cattle in the Northern Rocky Mountains raise the importance of research concerning maternal behavior around the time of parturition. Separation behavior of multiparous cows at parturition was studied by measuring the distance (m) between the birth place and the main herd with a GPS device. Age of cows and forehead hair whorl pattern (HW) were analyzed as possible factors affecting separation distance. A total of 333 cows (95% Red Angus and 5% Angus × Hereford commercial crossbreds;age range: 3 - 6 yrs) were studied. Separation distance was determined by approaching the cow-calf pair with a utility vehicle that gradually decreased the distance to the pair. The geographic coordinates per pair were recorded and the separation distance was calculated as a straight line between each pair and the main herd. The HW on the forehead of each animal was used as a measure of individual differences in temperament. Age and HW were collected when the animals were held in a squeeze chute. HW was classified into one of six groups: high, middle, low, abnormal, multiple HWs and no HW. The age of a cow influenced the separation distance for parturition (P < 0.001). Four-year-old cows were on average about 150 m further away than other aged cows when calving. Eighty-eight percent of cows separated more than 100 m from the herd. The hair whorl position had no influence on the separation distance (P = 0.405). Distinct separation behavior for parturition was observed in this herd which appears to be an innate behavior that is influenced by the individual temperament of the cow.展开更多
This review aimed to summarize the major progress in maternal-fetal medicine achieved by Chinese scientists in recent years.PubMed was systematically searched from January 2020 to November 2023.Publications that repor...This review aimed to summarize the major progress in maternal-fetal medicine achieved by Chinese scientists in recent years.PubMed was systematically searched from January 2020 to November 2023.Publications that reported the progress in embryo implantation,placentation,and parturition made by Chinese scientists in the last 3 years were selected.The milestone events during gestation,embryo implantation,endometrial decidualization,placentation,and parturition are pivotal to a successful pregnancy.Embryo implantation requires intricate interactions between implantation-competent blastocysts and receptive endometrium.To adapt to pregnancy,endometrial stromal cells transform into specialized decidual cells,which occur spontaneously under the influence of ovarian hormones in humans but require the presence of embryos in mice.With embryonic development,the placenta forms to support fetal growth until parturition.The maternal-fetal interface is composed of diverse cell types,including endometrial decidual cells,placental trophoblast cells,endothelial cells,and various immune cells,a sophisticated interplay among which contributes to the maintenance of pregnancy.Near term,the uterus transitions from quiescence to contractility,in preparation for delivery.Disruptions to these events lead to pregnancy-related disorders such as repeated implantation failure,recurrent pregnancy loss,preeclampsia,fetal growth restriction,preterm birth,and infertility.In recent years,Chinese scientists have made prominent achievements in basic research on the aforementioned pregnancy events.Chinese scientists have made remarkable contributions to reproductive biology and maternal-fetal medicine research in recent years,highlighting future research directions in this field.展开更多
Enhanced vegetation index(EVI)data can be used to identify and define the space in which ungulates practice parturition and encounter predation.This study explores the use of EVI data to identify landscapes linked to ...Enhanced vegetation index(EVI)data can be used to identify and define the space in which ungulates practice parturition and encounter predation.This study explores the use of EVI data to identify landscapes linked to ungulate parturition and predation events across space,time,and environmental conditions.As a case study,we used the moose population(Alces alces)of northern Minnesota in the USA.Using remotely sensed EVI data rasters and global positioning system collar data,we quantified how vegetation phenology and moose movement shaped the births and predation of 52 moose calves from 2013 to 2020 on or adjacent to the Grand Portage Indian Reservation.The known sources of predation were American black bears(Ursus americanus,n=22)and gray wolves(Canis lupus,n=28).Satellite-derived data summarizing seasonal landscape features at the local level revealed that landscape heterogeneity use by moose can help to quantitatively identify landscapes of parturition and predation in space and time across large areas.Vegetation phenology proved to be differentiable between adult moose ranges,sites of cow parturition,and sites of calf predation.Landscape characteristics of each moose group were consistent and tractable based on environment,suggesting that sites of parturition and predation of moose are predictable in space and time.It is possible that moose selected specific landscapes for parturition despite risk of increased predation of their calves,which could be an example of an"ecological trap."This analytical framework can be employed to identify areas for future ungulate research on the impacts of landscape on parturition and predation dynamics.展开更多
The second-stage of labor is the most stressful part of childbirth process and the proper maternal position during this period is paramount for women's safe vaginal birth.Midwives play a pivotal role in managing m...The second-stage of labor is the most stressful part of childbirth process and the proper maternal position during this period is paramount for women's safe vaginal birth.Midwives play a pivotal role in managing maternal positions during the second-stage of labor.However,there is limited evidence to support an ideal maternal position during the second-stage of labor.Further,the difference between different maternal positions might not be apparent.This paper aims to review and compare the benefits and risks of common maternal positions during the second-stage of labor,thereby to provide midwives evidence-based practical guidelines.展开更多
Purpose:To evaluate the effect of pelvic floor muscle training as a nursing intervention on delivery outcomes and postpartum pelvic floor myodynamia.Methods:In total,106 nulliparas were randomised into an intervention...Purpose:To evaluate the effect of pelvic floor muscle training as a nursing intervention on delivery outcomes and postpartum pelvic floor myodynamia.Methods:In total,106 nulliparas were randomised into an intervention group and control group.All nulliparas participated in a pelvic floor training programme led by a midwife.A pelvic floor physical therapist measured the women’s pelvic floor myodynamia and taught them how to correctly perform pelvic muscle contractions before the intervention.A registered nurse monitored the intervention group via twice-weekly telephone checkups.The control group did not receive individual direction.Results:There were no differences in the rate of Caesarean section or elective Caesarean section between the two groups(χ^(2)=3.446,p=0.076 and χ^(2)=2.343,p=0.185,respectively).There was a difference in the timing of the second stage of labour between the two groups(t=2.101,p=0.040);no difference was observed in the timing of the other two stages of labour(t=1.771,p=0.081 and t=1.142,p=0.263,respectively).In addition,no differences were observed in the gestational weight gain(t=0.196,p=0.845),neonatal weight(t=0.113,p=0.911),rate of episiotomy(χ^(2)=0.932,p=0.351)or rate of perineal laceration(χ^(2)=0.022,p=0.982)between the two groups.The pelvic floor myodynamia of the intervention group had improved to a greater degree than that in the control group at 6 weeks and 3 months after delivery(p<0.005).Conclusion:Persistent nursing intervention for pregnant/postpartum women helped to shorten the second stage of labour and contributed to the recovery of postpartum pelvic floor myodynamia.The influence of this intervention on the delivery mode,and rates of episiotomy and perineal laceration remains unknown.Medical staff should strengthen health education programmes that involve pelvic floor functional rehabilitation.展开更多
Background: Nutrition is one of the most important factors that affect animal performance, and it therefore also impacts on financial results in beef systems. In this way, finding the best strategy for feeding supplem...Background: Nutrition is one of the most important factors that affect animal performance, and it therefore also impacts on financial results in beef systems. In this way, finding the best strategy for feeding supplements is of paramount importance. Aiming to evaluate the effect of supplement feeding strategies for beef cows in the last third of gestation, two experiments were conducted. In Experiment 1, 35 pregnant Nellore cows were assigned to a completely randomized design with four treatments: control, which received no supplement; supplementation for the last 30 d of gestation(30-d; 3.0 kg/d); supplementation for the last 60 d of gestation(60-d; 1.5 kg/d); or supplementation for the last 90 d of gestation(90-d; 1.0 kg/d). All supplemented treatments received the same total amount of supplement throughout the experiment: 90 kg(20% of crude protein). A second experiment(Experiment 2) was delineated to evaluate the effects of the amounts offered in Experiment 1 on intake and metabolism. Four multiparous pregnant Nellore cows were assigned to a 4 × 4 Latin square design, with periods of15 d each.Results: There was a linear effect of the number of days of supplementation on calving body weight(BW; P < 0.05)and a quadratic effect on BW change from parturition to d 31 post-calving(P < 0.05), with cows on the 60-d strategy losing less BW post-calving. No difference was found in offspring birth BW(P > 0.10). A significant linear effect on interval from parturition to conception(P < 0.05) was observed, with the highest calving to conception interval being observed in the 90-d strategy. The level of supplementation did not affect forage intake or neutral detergent fiber digestibility(P > 0.10). Nitrogen excreted through urine tended to increase linearly with the level of supplementation(P < 0.10).Conclusion: Providing 1.5 kg of supplement during the last 60 d of gestation improves cow performance after calving, reducing the magnitude of BW lost, and reduces the number of days from calving to re-conception in the following breeding season compared to the usually recommended period of supplementation of 90 d pre-partum.展开更多
Objective: To determine which maternal characteristics or birth events independently predict severity of levator ani muscle (LA) tears at first vaginal birth in a longitudinal/observational investigation in a tertiary...Objective: To determine which maternal characteristics or birth events independently predict severity of levator ani muscle (LA) tears at first vaginal birth in a longitudinal/observational investigation in a tertiary care hospital. Sample: Ninety primiparas with at least one at risk for LA tear inclusion factor at vaginal birth: maternal age ≥ 33 years, second stage ≥ 150 minutes, macrosomia, instrumented delivery, and/or anal sphincter laceration were studied. Methods: Magnetic Resonance Imaging (MRI) was obtained early postpartum (mean ± sd 48.9 ± 21.6 days) to identify LA tear. Severity of LA muscle fiber loss was graded on an ordinal scale of: “0” as no loss, “1” as <50% unilateral loss, “2” as ≥50% unilateral or <50% bilateral loss, and “3” as ≥50% bilateral loss. Data were analyzed using proportional odds modeling. Inclusion factors were explored as predictors of LA tear severity and at analysis episiotomy, time spent actively pushing, epidural, and oxytocin were also considered. The main outcome measures of interest included grading of severity of LA muscle fiber loss on an ordinal scale. Results: Respective counts/percentages of women within each 0 thru 3 ordered category of LA tear severity were: “0” = 58(64%), “1” = 9(10%), “2” = 15(17%), and “3” = 8(9%). Estimates and 95% CI for significant demographic or obstetric univariate predictors of LA tear severity level were age, OR 1.093 (CI 1.012 - 1.180), p = 0.023;and time spent in active pushing, OR 1.089 (CI 1.005 - 1.180), p = 0.038. The other factors considered were not significant. There were too few women with forceps deliveries to analyze. Conclusion: In our enriched sample of primiparous women, 26% showed a significant LA tear. Maternal age and time spent actively pushing independently predict LA tear severity.展开更多
We previously investigated the progesterone metabolite 5β-dihydroprogesterone (5βDHP) in relation to human parturition at term, demonstrating that peripheral venous concentrations decrease in association with the on...We previously investigated the progesterone metabolite 5β-dihydroprogesterone (5βDHP) in relation to human parturition at term, demonstrating that peripheral venous concentrations decrease in association with the onset of spontaneous labour. In this study our aim was to determine if 5βDHP concentrations were lower in women presenting in spontaneous preterm labour than in controls matched for gestational age. Blood samples were obtained from women presenting in spontaneous preterm labour (n = 20). The diagnosis was made on the presence of regular contractions and cervical effacement and dilatation of at least 3 cms. All women in the preterm labour group delivered before 37 weeks gestation. Blood samples were then obtained from controls, closely matched for gestational age with uncomplicated pregnancies. The preterm labour group was further stratified by cause into three groups, chorioamnionitis (n = 5), abruption (n = 4) and idiopathic (n = 11). Following organic solvent extraction, steroids were separated by HPLC and 5βDHP quantified by radioimmunoassay. Women in the idiopathic preterm labour group were found to have significantly lower circulating concentrations of 5βDHP than controls展开更多
An 8 years old Murrah buffalo in its 5^(th) party was presented with the history of 9 month of gestation and sudden bilateral abdominal distension since last 25 days.Animal was 7 anorectic with pale mucus membrane and...An 8 years old Murrah buffalo in its 5^(th) party was presented with the history of 9 month of gestation and sudden bilateral abdominal distension since last 25 days.Animal was 7 anorectic with pale mucus membrane and had staggering gait.Per vaginum examination revealed closed cervix with intact cervical seal.By transrectal palpation only the fluid in the uterus could be palpable.Based on history and clinical examination findings,it was diagnosed as hydroallantois.Parturition was induced using cloprostenol and dexamethasone.Beside this an intracervical injection of closprostenol was also given on 6 o’clock and 12 o’clock position(250μg each)of external os to hasten the cervical dilation.A dead bulldog calf was removed with manual traction after 26 hours of initial treatment.It was concluded that the cloprostenol and dexamethasone are effective for the induction of parturition in animals suffering from hydroallantois provided fluid from the allantoic sac is removed slowly.展开更多
Preterm delivery is a major global health problem associated with increased neonatal morbidity and mortality.To develop effective strategies to reduce preterm birth,it is important to address the causes of and risk fa...Preterm delivery is a major global health problem associated with increased neonatal morbidity and mortality.To develop effective strategies to reduce preterm birth,it is important to address the causes of and risk factors for this condition.Maternal metabolism plays a crucial role in pregnancy outcomes,as it affects the availability of nutrients,energy,and other essential factors required for fetal development and growth.Several aspects of maternal metabolism can potentially contribute to the risk of preterm delivery.Severe energy deficiency as observed in women suffering from eating disorders can affect the hypothalamic-pituitary-gonadal axis resulting in amenorrhea and infertility,suggesting that maintaining a minimum maternal weight is essential to uphold a functional reproductive system,thus ensuring a successful pregnancy.Maternal undernutrition as observed in past famine and observations and animal studies may affect fetal growth and trigger an early activation of the parturition pathway leading to preterm delivery.A correlation exists between maternal size and gestation duration.Obesity is associated with a higher likelihood of medically indicated preterm birth.Low maternal body mass index and low gestational weight gain during pregnancy have been associated with preterm birth,potentially due to fetal-maternal metabolic imbalance;however,the exact mechanism remains to be determined,thus emphasizing the importance of appropriate weight management before and during pregnancy.Addressing metabolic-related risk factors for preterm delivery requires a comprehensive approach to reduce the burden of preterm delivery and improve neonatal outcomes.This review aims to explore various aspects of fetal-maternal metabolic imbalance that could potentially contribute to preterm birth.By doing so,we suggest a novel and comprehensive approach that sheds light on the intricate connection between fetal-maternal imbalance and the susceptibility to preterm birth.展开更多
Preterm birth is the leading cause of mortality and morbidity in newborns and children under 5 years-of-age.In order to improve the survival rate and quality of preterm infants,there is critical need to identify the s...Preterm birth is the leading cause of mortality and morbidity in newborns and children under 5 years-of-age.In order to improve the survival rate and quality of preterm infants,there is critical need to identify the specific mechanisms underlying the initiation of labor.Pregnancy represents a period of constant interactive dialog between mother and fetus.A disturbance in the pattern of maternal-fetal communication can induce physiological or pathological labor.Although a number of studies have investigated the contributions of maternal factors to the initiation of labor,the concept that fetal organ development and maternal adaptation are coordinated has emerged over recent years,thus emphasizing that factors of fetal origin may serve as hormonal signals for the initiation of labor.In this review,we summarize and discuss several specific mechanisms by which factors of fetal origin may influence parturition during term or preterm labor,including the specific regulation of fetal organs,including the lungs and accessory organs during pregnancy.Future research may focus on the specific pathways by which signals from the fetal lungs and other fetal organs interact with the maternal system to initiate eventual labor.展开更多
Pregnancy is a state of immunological balance during which the mother and the developing fetus must tolerate each other while maintaining sufficient immunocompetence to ward off potential threats.The site of closest c...Pregnancy is a state of immunological balance during which the mother and the developing fetus must tolerate each other while maintaining sufficient immunocompetence to ward off potential threats.The site of closest contact between the mother and fetus is the decidua,which represents the maternal–fetal interface.Many of the immune cell subsets present at the maternal–fetal interface have been well described;however,the importance of the maternal T cells in this compartment during late gestation and its complications,such as preterm labor and birth,has only recently been established.Moreover,pioneer and recent studies have indicated that fetal T cells are activated in different subsets of preterm labor and may elicit distinct inflammatory responses in the amniotic cavity,leading to preterm birth.In this review,we describe the established and proposed roles for maternal T cells at the maternal–fetal interface in normal term parturition,as well as the demonstrated contributions of such cells to the pathological process of preterm labor and birth.We also summarize the current knowledge of and proposed roles for fetal T cells in the pathophysiology of the preterm labor syndrome.It is our hope that this review provides a solid conceptual framework highlighting the importance of maternal and fetal T cells in late gestation and catalyzes new research questions that can further scientific understanding of these cells and their role in preterm labor and birth,the leading cause of neonatal mortality and morbidity worldwide.展开更多
INCREASING evidence has demonstrated that the locally controlled proteolytic activity generatedby coordinated expression of tPA and PAI-1 in different tissues may play an important role inmany reproductive events. The...INCREASING evidence has demonstrated that the locally controlled proteolytic activity generatedby coordinated expression of tPA and PAI-1 in different tissues may play an important role inmany reproductive events. These are largely related to fibrinolytic activity. They include folli-cle rupture, luteolysis, spermatogenesis and trophoblast implantation. Parturition, whichis a complex process, may also be associated with tissue destruction. Detachment of placentaldecidua and partial breakdown of fetal membranes are possible examples. It has been展开更多
While most mammals show birth hour peaks at times of the 24-h cycle when they are less active,there are exceptions to this general pattern.Such exceptions have been little explored,but may clarify evolutionary reasons...While most mammals show birth hour peaks at times of the 24-h cycle when they are less active,there are exceptions to this general pattern.Such exceptions have been little explored,but may clarify evolutionary reasons for the diel timing of births.We investigated intraspecific variation in birth hour in wild blue monkeys Cercopithecus mitis stuhlmanni,a diurnal primate,to identify factors that differentiated daytime versus nighttime births.Behavioral and life history data from 14 groups over 14 years revealed that 4%of 484 births occurred during the day.Probability of daytime birth varied with mother’s age,peaking at 15.7 years.Births whose annual timing deviated most from the population’s peak birth months were 5 times more likely to occur during daytime than those that deviated less.There was no evidence that mother’s rank or infant sex influenced birth hour,and mixed evidence that daytime births were more probable in larger groups.Survivorship did not differ significantly for infants born during the day versus night.Prime-aged mothers may be able to handle the consequences of an unusual birth hour more successfully than mothers with less experience or those weakened by age.Daytime birth may be more advantageous in the off-season because nights are colder at that time of year.These findings are consistent with hypotheses relating birth hour to the risk of losing social protection in group-living animals,but are not consistent with those emphasizing risk of conspecific harassment.Patterns of within-species variation can help in evaluating evolutionary hypotheses for non-random birth hour.展开更多
文摘Background: The aims of this study were(a) to ascertain age-related changes in the reference values in hematological and serum biochemical examinations of beagles,and(b) to clarify the changes in these findings, including acute phase proteins and oxidative stress, throughout pregnancy and after parturition.Methods: Clinicopathological parameters were measured in young beagles at 6, 9 and 12 months and in adult beagles aged from 24 to 60 months. Likewise, pregnant beagles were investigated throughout the pregnancy and after parturition.Results: Apparent age-related changes were found in erythrocytic parameters during the growth and development of beagles. Most of the parameters(total protein,albumin, blood urea nitrogen, creatinine, urate, alkaline phosphatase(ALP) and creatine kinase(CK) exhibited age-dependent transitions. White cell count significantly increased after 30 days of pregnancy. The values of erythrocytic parameters moderately decreased during the second half of the pregnancy. Triglycerides, total cholesterol, free cholesterol and phospholipid concentrations increased in the mid- and late stages of pregnancy. ALP, lactate dehydrogenase, CK and cholinesterase activities markedly increased during pregnancy and/or after parturition. C-reactive protein(CRP) concentrations gradually increased and reached a maximum after 30-40 days of pregnancy. Serum amyloid A(SAA) levels markedly increased at 30 days of pregnancy before subsiding, and then increased again 3 days after parturition. Reactive oxygen metabolites(d-ROMs) showed significant increases after 30 and 40 days of pregnancy.Conclusions: Reference values for hematological and serum biochemical examinations should be used for health evaluation of dogs, taking sex, age and the stage of pregnancy into consideration. Measurements of CRP, SAA and d-ROM levels are also useful for assessing maternal conditions in mid-pregnancy.
文摘Increased predation losses in beef cattle in the Northern Rocky Mountains raise the importance of research concerning maternal behavior around the time of parturition. Separation behavior of multiparous cows at parturition was studied by measuring the distance (m) between the birth place and the main herd with a GPS device. Age of cows and forehead hair whorl pattern (HW) were analyzed as possible factors affecting separation distance. A total of 333 cows (95% Red Angus and 5% Angus × Hereford commercial crossbreds;age range: 3 - 6 yrs) were studied. Separation distance was determined by approaching the cow-calf pair with a utility vehicle that gradually decreased the distance to the pair. The geographic coordinates per pair were recorded and the separation distance was calculated as a straight line between each pair and the main herd. The HW on the forehead of each animal was used as a measure of individual differences in temperament. Age and HW were collected when the animals were held in a squeeze chute. HW was classified into one of six groups: high, middle, low, abnormal, multiple HWs and no HW. The age of a cow influenced the separation distance for parturition (P < 0.001). Four-year-old cows were on average about 150 m further away than other aged cows when calving. Eighty-eight percent of cows separated more than 100 m from the herd. The hair whorl position had no influence on the separation distance (P = 0.405). Distinct separation behavior for parturition was observed in this herd which appears to be an innate behavior that is influenced by the individual temperament of the cow.
基金supported by the National Key R&D Program of China (2022YFC2702500 and 2021YFC2700302)National Natural Science Foundation of China (82288102).
文摘This review aimed to summarize the major progress in maternal-fetal medicine achieved by Chinese scientists in recent years.PubMed was systematically searched from January 2020 to November 2023.Publications that reported the progress in embryo implantation,placentation,and parturition made by Chinese scientists in the last 3 years were selected.The milestone events during gestation,embryo implantation,endometrial decidualization,placentation,and parturition are pivotal to a successful pregnancy.Embryo implantation requires intricate interactions between implantation-competent blastocysts and receptive endometrium.To adapt to pregnancy,endometrial stromal cells transform into specialized decidual cells,which occur spontaneously under the influence of ovarian hormones in humans but require the presence of embryos in mice.With embryonic development,the placenta forms to support fetal growth until parturition.The maternal-fetal interface is composed of diverse cell types,including endometrial decidual cells,placental trophoblast cells,endothelial cells,and various immune cells,a sophisticated interplay among which contributes to the maintenance of pregnancy.Near term,the uterus transitions from quiescence to contractility,in preparation for delivery.Disruptions to these events lead to pregnancy-related disorders such as repeated implantation failure,recurrent pregnancy loss,preeclampsia,fetal growth restriction,preterm birth,and infertility.In recent years,Chinese scientists have made prominent achievements in basic research on the aforementioned pregnancy events.Chinese scientists have made remarkable contributions to reproductive biology and maternal-fetal medicine research in recent years,highlighting future research directions in this field.
基金This project was funded by the U.S.Fish and Wildlife Service Tribal Wildlife Grant,U.S.Environmental Protection Agency Great Lakes Restoration InitiativeBureau of Indian Affairs Endangered Species Program+1 种基金Funding was also provided by the Minnesota Zoo Ulysses S.Seal Conservation GrantIndianapolis Zoo Conservation Fund.
文摘Enhanced vegetation index(EVI)data can be used to identify and define the space in which ungulates practice parturition and encounter predation.This study explores the use of EVI data to identify landscapes linked to ungulate parturition and predation events across space,time,and environmental conditions.As a case study,we used the moose population(Alces alces)of northern Minnesota in the USA.Using remotely sensed EVI data rasters and global positioning system collar data,we quantified how vegetation phenology and moose movement shaped the births and predation of 52 moose calves from 2013 to 2020 on or adjacent to the Grand Portage Indian Reservation.The known sources of predation were American black bears(Ursus americanus,n=22)and gray wolves(Canis lupus,n=28).Satellite-derived data summarizing seasonal landscape features at the local level revealed that landscape heterogeneity use by moose can help to quantitatively identify landscapes of parturition and predation in space and time across large areas.Vegetation phenology proved to be differentiable between adult moose ranges,sites of cow parturition,and sites of calf predation.Landscape characteristics of each moose group were consistent and tractable based on environment,suggesting that sites of parturition and predation of moose are predictable in space and time.It is possible that moose selected specific landscapes for parturition despite risk of increased predation of their calves,which could be an example of an"ecological trap."This analytical framework can be employed to identify areas for future ungulate research on the impacts of landscape on parturition and predation dynamics.
文摘The second-stage of labor is the most stressful part of childbirth process and the proper maternal position during this period is paramount for women's safe vaginal birth.Midwives play a pivotal role in managing maternal positions during the second-stage of labor.However,there is limited evidence to support an ideal maternal position during the second-stage of labor.Further,the difference between different maternal positions might not be apparent.This paper aims to review and compare the benefits and risks of common maternal positions during the second-stage of labor,thereby to provide midwives evidence-based practical guidelines.
基金2010 Youth Fund Project of Guangzhou Medical University(Project number:2010A03).
文摘Purpose:To evaluate the effect of pelvic floor muscle training as a nursing intervention on delivery outcomes and postpartum pelvic floor myodynamia.Methods:In total,106 nulliparas were randomised into an intervention group and control group.All nulliparas participated in a pelvic floor training programme led by a midwife.A pelvic floor physical therapist measured the women’s pelvic floor myodynamia and taught them how to correctly perform pelvic muscle contractions before the intervention.A registered nurse monitored the intervention group via twice-weekly telephone checkups.The control group did not receive individual direction.Results:There were no differences in the rate of Caesarean section or elective Caesarean section between the two groups(χ^(2)=3.446,p=0.076 and χ^(2)=2.343,p=0.185,respectively).There was a difference in the timing of the second stage of labour between the two groups(t=2.101,p=0.040);no difference was observed in the timing of the other two stages of labour(t=1.771,p=0.081 and t=1.142,p=0.263,respectively).In addition,no differences were observed in the gestational weight gain(t=0.196,p=0.845),neonatal weight(t=0.113,p=0.911),rate of episiotomy(χ^(2)=0.932,p=0.351)or rate of perineal laceration(χ^(2)=0.022,p=0.982)between the two groups.The pelvic floor myodynamia of the intervention group had improved to a greater degree than that in the control group at 6 weeks and 3 months after delivery(p<0.005).Conclusion:Persistent nursing intervention for pregnant/postpartum women helped to shorten the second stage of labour and contributed to the recovery of postpartum pelvic floor myodynamia.The influence of this intervention on the delivery mode,and rates of episiotomy and perineal laceration remains unknown.Medical staff should strengthen health education programmes that involve pelvic floor functional rehabilitation.
基金supported by funding from Fapemig–Fundacao de AmparoàPesquisa de MG,CNPq–Conselho Nacional de Desenvolvimento Científico e Tecnológico and Capes–Coordenacao de Aperfeicoamento de Pessoal de Nível Superior
文摘Background: Nutrition is one of the most important factors that affect animal performance, and it therefore also impacts on financial results in beef systems. In this way, finding the best strategy for feeding supplements is of paramount importance. Aiming to evaluate the effect of supplement feeding strategies for beef cows in the last third of gestation, two experiments were conducted. In Experiment 1, 35 pregnant Nellore cows were assigned to a completely randomized design with four treatments: control, which received no supplement; supplementation for the last 30 d of gestation(30-d; 3.0 kg/d); supplementation for the last 60 d of gestation(60-d; 1.5 kg/d); or supplementation for the last 90 d of gestation(90-d; 1.0 kg/d). All supplemented treatments received the same total amount of supplement throughout the experiment: 90 kg(20% of crude protein). A second experiment(Experiment 2) was delineated to evaluate the effects of the amounts offered in Experiment 1 on intake and metabolism. Four multiparous pregnant Nellore cows were assigned to a 4 × 4 Latin square design, with periods of15 d each.Results: There was a linear effect of the number of days of supplementation on calving body weight(BW; P < 0.05)and a quadratic effect on BW change from parturition to d 31 post-calving(P < 0.05), with cows on the 60-d strategy losing less BW post-calving. No difference was found in offspring birth BW(P > 0.10). A significant linear effect on interval from parturition to conception(P < 0.05) was observed, with the highest calving to conception interval being observed in the 90-d strategy. The level of supplementation did not affect forage intake or neutral detergent fiber digestibility(P > 0.10). Nitrogen excreted through urine tended to increase linearly with the level of supplementation(P < 0.10).Conclusion: Providing 1.5 kg of supplement during the last 60 d of gestation improves cow performance after calving, reducing the magnitude of BW lost, and reduces the number of days from calving to re-conception in the following breeding season compared to the usually recommended period of supplementation of 90 d pre-partum.
文摘Objective: To determine which maternal characteristics or birth events independently predict severity of levator ani muscle (LA) tears at first vaginal birth in a longitudinal/observational investigation in a tertiary care hospital. Sample: Ninety primiparas with at least one at risk for LA tear inclusion factor at vaginal birth: maternal age ≥ 33 years, second stage ≥ 150 minutes, macrosomia, instrumented delivery, and/or anal sphincter laceration were studied. Methods: Magnetic Resonance Imaging (MRI) was obtained early postpartum (mean ± sd 48.9 ± 21.6 days) to identify LA tear. Severity of LA muscle fiber loss was graded on an ordinal scale of: “0” as no loss, “1” as <50% unilateral loss, “2” as ≥50% unilateral or <50% bilateral loss, and “3” as ≥50% bilateral loss. Data were analyzed using proportional odds modeling. Inclusion factors were explored as predictors of LA tear severity and at analysis episiotomy, time spent actively pushing, epidural, and oxytocin were also considered. The main outcome measures of interest included grading of severity of LA muscle fiber loss on an ordinal scale. Results: Respective counts/percentages of women within each 0 thru 3 ordered category of LA tear severity were: “0” = 58(64%), “1” = 9(10%), “2” = 15(17%), and “3” = 8(9%). Estimates and 95% CI for significant demographic or obstetric univariate predictors of LA tear severity level were age, OR 1.093 (CI 1.012 - 1.180), p = 0.023;and time spent in active pushing, OR 1.089 (CI 1.005 - 1.180), p = 0.038. The other factors considered were not significant. There were too few women with forceps deliveries to analyze. Conclusion: In our enriched sample of primiparous women, 26% showed a significant LA tear. Maternal age and time spent actively pushing independently predict LA tear severity.
文摘We previously investigated the progesterone metabolite 5β-dihydroprogesterone (5βDHP) in relation to human parturition at term, demonstrating that peripheral venous concentrations decrease in association with the onset of spontaneous labour. In this study our aim was to determine if 5βDHP concentrations were lower in women presenting in spontaneous preterm labour than in controls matched for gestational age. Blood samples were obtained from women presenting in spontaneous preterm labour (n = 20). The diagnosis was made on the presence of regular contractions and cervical effacement and dilatation of at least 3 cms. All women in the preterm labour group delivered before 37 weeks gestation. Blood samples were then obtained from controls, closely matched for gestational age with uncomplicated pregnancies. The preterm labour group was further stratified by cause into three groups, chorioamnionitis (n = 5), abruption (n = 4) and idiopathic (n = 11). Following organic solvent extraction, steroids were separated by HPLC and 5βDHP quantified by radioimmunoassay. Women in the idiopathic preterm labour group were found to have significantly lower circulating concentrations of 5βDHP than controls
文摘An 8 years old Murrah buffalo in its 5^(th) party was presented with the history of 9 month of gestation and sudden bilateral abdominal distension since last 25 days.Animal was 7 anorectic with pale mucus membrane and had staggering gait.Per vaginum examination revealed closed cervix with intact cervical seal.By transrectal palpation only the fluid in the uterus could be palpable.Based on history and clinical examination findings,it was diagnosed as hydroallantois.Parturition was induced using cloprostenol and dexamethasone.Beside this an intracervical injection of closprostenol was also given on 6 o’clock and 12 o’clock position(250μg each)of external os to hasten the cervical dilation.A dead bulldog calf was removed with manual traction after 26 hours of initial treatment.It was concluded that the cloprostenol and dexamethasone are effective for the induction of parturition in animals suffering from hydroallantois provided fluid from the allantoic sac is removed slowly.
文摘Preterm delivery is a major global health problem associated with increased neonatal morbidity and mortality.To develop effective strategies to reduce preterm birth,it is important to address the causes of and risk factors for this condition.Maternal metabolism plays a crucial role in pregnancy outcomes,as it affects the availability of nutrients,energy,and other essential factors required for fetal development and growth.Several aspects of maternal metabolism can potentially contribute to the risk of preterm delivery.Severe energy deficiency as observed in women suffering from eating disorders can affect the hypothalamic-pituitary-gonadal axis resulting in amenorrhea and infertility,suggesting that maintaining a minimum maternal weight is essential to uphold a functional reproductive system,thus ensuring a successful pregnancy.Maternal undernutrition as observed in past famine and observations and animal studies may affect fetal growth and trigger an early activation of the parturition pathway leading to preterm delivery.A correlation exists between maternal size and gestation duration.Obesity is associated with a higher likelihood of medically indicated preterm birth.Low maternal body mass index and low gestational weight gain during pregnancy have been associated with preterm birth,potentially due to fetal-maternal metabolic imbalance;however,the exact mechanism remains to be determined,thus emphasizing the importance of appropriate weight management before and during pregnancy.Addressing metabolic-related risk factors for preterm delivery requires a comprehensive approach to reduce the burden of preterm delivery and improve neonatal outcomes.This review aims to explore various aspects of fetal-maternal metabolic imbalance that could potentially contribute to preterm birth.By doing so,we suggest a novel and comprehensive approach that sheds light on the intricate connection between fetal-maternal imbalance and the susceptibility to preterm birth.
基金Research in the Gao's laboratory is supported by National Key Research and Development Project 2022YFC2704602 and 2022YFC2704502National Natural Science Foundation of China 82120108011+1 种基金Major Project of Shanghai Municipal Education Commission’s Scientific Research and Innovation Plan 2021-01-07-00-07-E00144Strategic Collaborative Research Program of the Ferring Institute of Reproductive Medicine FIRMA200502.
文摘Preterm birth is the leading cause of mortality and morbidity in newborns and children under 5 years-of-age.In order to improve the survival rate and quality of preterm infants,there is critical need to identify the specific mechanisms underlying the initiation of labor.Pregnancy represents a period of constant interactive dialog between mother and fetus.A disturbance in the pattern of maternal-fetal communication can induce physiological or pathological labor.Although a number of studies have investigated the contributions of maternal factors to the initiation of labor,the concept that fetal organ development and maternal adaptation are coordinated has emerged over recent years,thus emphasizing that factors of fetal origin may serve as hormonal signals for the initiation of labor.In this review,we summarize and discuss several specific mechanisms by which factors of fetal origin may influence parturition during term or preterm labor,including the specific regulation of fetal organs,including the lungs and accessory organs during pregnancy.Future research may focus on the specific pathways by which signals from the fetal lungs and other fetal organs interact with the maternal system to initiate eventual labor.
基金This research was supported by the Wayne State University Perinatal Initiative in Maternal,Perinatal and Child Health and the Perinatology Research Branch,Division of Obstetrics and Maternal–Fetal Medicine,Division of Intramural Research,Eunice Kennedy Shriver National Institute of Child Health and Human Development,National Institutes of Health,U.S.Department of Health and Human Services(NICHD/NIH/DHHS)in part,with federal funds from NICHD/NIH/DHHS under Contract no.HHSN275201300006C.Dr.Romero has contributed to this work as part of his official duties as an employee of the United States Federal Government.
文摘Pregnancy is a state of immunological balance during which the mother and the developing fetus must tolerate each other while maintaining sufficient immunocompetence to ward off potential threats.The site of closest contact between the mother and fetus is the decidua,which represents the maternal–fetal interface.Many of the immune cell subsets present at the maternal–fetal interface have been well described;however,the importance of the maternal T cells in this compartment during late gestation and its complications,such as preterm labor and birth,has only recently been established.Moreover,pioneer and recent studies have indicated that fetal T cells are activated in different subsets of preterm labor and may elicit distinct inflammatory responses in the amniotic cavity,leading to preterm birth.In this review,we describe the established and proposed roles for maternal T cells at the maternal–fetal interface in normal term parturition,as well as the demonstrated contributions of such cells to the pathological process of preterm labor and birth.We also summarize the current knowledge of and proposed roles for fetal T cells in the pathophysiology of the preterm labor syndrome.It is our hope that this review provides a solid conceptual framework highlighting the importance of maternal and fetal T cells in late gestation and catalyzes new research questions that can further scientific understanding of these cells and their role in preterm labor and birth,the leading cause of neonatal mortality and morbidity worldwide.
文摘INCREASING evidence has demonstrated that the locally controlled proteolytic activity generatedby coordinated expression of tPA and PAI-1 in different tissues may play an important role inmany reproductive events. These are largely related to fibrinolytic activity. They include folli-cle rupture, luteolysis, spermatogenesis and trophoblast implantation. Parturition, whichis a complex process, may also be associated with tissue destruction. Detachment of placentaldecidua and partial breakdown of fetal membranes are possible examples. It has been
基金the U.S.National Science Foundation(SBE 9523623,BCS 9808273,DGE 0333415,BCS 0554747,DGE 0966166,BCS 1028471),Ford,Leakey,Wenner-Gren and H.F.Guggenheim Foundations,American Association for the Advancement of Science-Women's International Scientific Cooperation Project,and Columbia University,all to M.C.
文摘While most mammals show birth hour peaks at times of the 24-h cycle when they are less active,there are exceptions to this general pattern.Such exceptions have been little explored,but may clarify evolutionary reasons for the diel timing of births.We investigated intraspecific variation in birth hour in wild blue monkeys Cercopithecus mitis stuhlmanni,a diurnal primate,to identify factors that differentiated daytime versus nighttime births.Behavioral and life history data from 14 groups over 14 years revealed that 4%of 484 births occurred during the day.Probability of daytime birth varied with mother’s age,peaking at 15.7 years.Births whose annual timing deviated most from the population’s peak birth months were 5 times more likely to occur during daytime than those that deviated less.There was no evidence that mother’s rank or infant sex influenced birth hour,and mixed evidence that daytime births were more probable in larger groups.Survivorship did not differ significantly for infants born during the day versus night.Prime-aged mothers may be able to handle the consequences of an unusual birth hour more successfully than mothers with less experience or those weakened by age.Daytime birth may be more advantageous in the off-season because nights are colder at that time of year.These findings are consistent with hypotheses relating birth hour to the risk of losing social protection in group-living animals,but are not consistent with those emphasizing risk of conspecific harassment.Patterns of within-species variation can help in evaluating evolutionary hypotheses for non-random birth hour.
