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This paper explores the maternal body work practices of black low-income mothers from resource-poor urban spaces in South Africa. Using Southern Theory to open our analytical lens, we recognise that location has implications for how we understand the embodiment of gender and the lactating body in the global South. We argue that maternal body work, as one form of gendered embodiment, must be understood in a postcolonial landscape where histories of colonisation and indigenous gender orders continue to shape how women respond to work conditions and how they manage the competing demands of work and breastfeeding. Our analysis from 51 in-depth interviews conducted in Cape Town, demonstrates that maternal body work practices are interpreted through the entanglement of embodiment and work and non-work spaces. By emphasising contextual specificities relating to low-income worker’s living, working and family realities, we advance studies on maternal body work and employment from the global South.

OBJECTIVE To examine the effects of maternal body mass index (BMI) and gestational age (GA) on the number of single circulating trophoblasts (SCT). METHODS Maternal blood was collected in 20 to 40 mL. All singleton pregnant women at any gestation were recruited. Trophoblasts were recovered by immunomagnetic enrichment and stained for cytokeratin and CD45. Candidate trophoblasts were identified by fluorescence microscopy. RESULTS Blood samples were collected from 425 singleton pregnancies from April 2018 to December 2019. At least one candidate cell was identified in 88% (373/425). There was an inverse correlation between trophoblasts yield and increasing BMI (r = -0.19, P

BACKGROUND: The association between physical activity and adiposity in preschool-aged children is unclear. OBJECTIVE: To assess the cross-sectional association between objectively measured physical activity and body fat in preschool-aged children. METHODS: In the preschool review in an Australian birth cohort study (n = 1074), mean duration and time accumulated in ≥1-min bouts of physical activity at light-intensity (LPA), moderate- to vigorous-intensity (MVPA) and light- to vigorous-intensity (LMVPA) were computed from accelerometer (ActiGraph GT3X+) data. Percent body fat was assessed by bioelectrical impedance. Associations between physical activity and percent body fat were examined by multiple regression, adjusted for accelerometer wear time, MVPA (in analyses of LPA), maternal body mass index (BMI) and maternal education. RESULTS: A total of 450 participants (n = 450) had valid data. There was evidence of associations between physical activity and adiposity: each additional hour of LVPA was associated with 0.6% (CI95 -0.2%, 1.3%) higher body fat; ≥1-min bouts of LPA was associated with 1.0% (CI95 0.1%, 1.9%) higher body fat; each additional hour of MVPA was associated with -0.8% (CI95 -1.6%, -0.1%) less body fat; and ≥1-min bouts of MVPA was associated with -1.3% (CI95 -2.5%, -0.1%) body fat. CONCLUSIONS: Among a cohort of preschool-aged children, there was evidence that more intensive physical activity assessed by an accelerometer is associated with reduced body fat.

Introduction Obese primiparous women with induction of labor are at high risk for a cesarean section. There are contradictory results regarding time in induced labor in relation to maternal body mass index (BMI). It is important to characterize the course of induced labor to prevent unnecessary cesarean section. We aimed to evaluate whether the duration of labor was associated with maternal BMI in primiparous women with induction of labor. Material and methods A national retrospective cohort study, including 15 259 primiparae with a single term pregnancy, admitted for induction of labor from January 2014 to August 2017. Data were obtained from the Swedish Pregnancy Registry. Cox regression analyses were used to illustrate the association between BMI and active labor and between BMI and time from admission until start of active labor. Results Duration of active labor was shorter in underweight women and prolonged in women with BMI amp;gt;= 40 kg/m(2) compared with women in other BMI classes, illustrated by Cox regression graphs (P amp;lt; .001). The median durations of active labor in underweight women were 6.1 and 7.4 hours in women with BMI amp;gt;= 40 kg/m(2). The time from admission until start of active labor increased with maternal BMI, illustrated by Cox regression graphs (P amp;lt; .001) and the median duration increased from 12.9 hours in underweight women to 22.6 hours in women with BMI amp;gt;= 40 kg/m(2). The cesarean section rate in active labor increased significantly with BMI (P amp;lt; .001) from 7.4% in underweight women to 22.0% in women with BMI amp;gt;= 40 kg/m(2). Obese and normal weight women had similar rates of spontaneous vaginal delivery (69.9% in the total study population). Conclusions The duration of active labor was associated with maternal BMI for underweight women and women with BMI amp;gt;= 40 kg/m(2). Although women with BMI amp;gt;= 40 kg/m(2) who reached the active phase of labor had the same chance for a spontaneous vaginal delivery as normal weight women, the duration of active labor and the cesarean section rate were increased. The time from admission until start of active labor increased successively with maternal BMI. Funding Agencies|ALF-grants Region Ostergotland Sweden

The number of obese pregnant women is increasing. Increased maternal body habitus is related to greater maternal health risks and an increased risk of fetal anomalies. The 18-20-week morphology scan is a routine clinical tool to detect fetal viability, anomalies, gestational age and number. Suboptimal ultrasound visualisation (SUV) affecting image quality increases with larger body habitus. This results in longer scanning times, incomplete and repeat scans, misdiagnosis, sonographer injuries and patient disappointment. This review aims to establish the effect increased maternal body habitus has on ultrasound image quality, specifically, the relationship between maternal body habitus and the 18-20-week morphology scan and detection of fetal anomalies. Inability to assess fetal structures due to SUV creates great challenges for the health system, imaging departments and patients. Studies have used different variables to measure the effect SUV has on the detection of fetal anomalies in obese women such as prenatal/neonatal comparisons, scan completion rates, the number of repeated scans and subjective judgements about diagnostic image quality. Some studies also included other influences such as fetal lie or placental position. Most studies concluded that a linear relationship exists between increased body habitus and decreased detection of fetal anomalies due to SUV particularly cardiac structures. Refereed/Peer-reviewed

Objective Little is known regarding maternal influences on the body image and eating concerns of young children. The current study aimed to examine the cross-sectional and longitudinal relationships between maternal comments about their child's weight and shape and eating, and mothers' own body dissatisfaction and disordered eating on one hand, and their children's body esteem and disordered eating behaviors on the other. Method Children, n = 244 of the fifth wave, aged 7 years (58% female), and n = 194 of the sixth wave, aged 8 years (57% female), of the longitudinal Children's Body Image Development Study, in Melbourne, Australia were included. Mothers completed measures of body dissatisfaction, dietary restraint, and comments and concerns regarding their children's weight and eating behaviors. They also reported on their children's disordered eating behaviors. Children's body esteem was assessed through a child interview. Results Findings revealed cross-sectional and prospective bivariate relationships between maternal comments and disordered eating behaviors among both boys and girls. Similar patterns of relationships emerged between maternal body dissatisfaction and lower child body esteem. Conclusion Findings highlight the importance of conducting prevention within the family environment from a young age, and targeting both direct communication as well as parental body image and eating behaviors.

he long‐term studies included in this paper were funded by the Natural Environment Research Council through the grant ‘SMRU Long‐term measurement of marine mammal population structure, dynamics and trophic interactions’, grant reference SMRU1001. PP was in receipt of NERC grant no. NE/G008930/1 and Esmée Fairbairn Foundation funding during the work. SCS was supported as a postdoctoral fellow in an EPSRC award to RK and PP. 1. Capital breeding animals such as true seals (Phocidae) rely on accumulated body reserves to rear offspring. A mother's body composition at the start of a breeding episode may depend on recent environmental conditions and sets the resources available for the reproductive episode. 2. At two grey seal (Halichoerus grypus) breeding colonies with contrasting demographic characteristics, factors influencing individual variation and temporal trends in the body composition (expressed as the lipid‐to‐protein mass ratio) of females were examined. 3. Maternal reproductive expenditure, and the consequences for mothers and their pups, were investigated. 4. Individual variation in postpartum maternal body composition was considerable. Mean values of 27% (±5%) lipid and 18% (±1%) protein were estimated by hydrogen isotope dilution. No evidence of age effects was detected. 5. Mothers with a high lipid‐to‐protein mass ratio expended a higher proportion of lipid resources, conserved protein and returned with more protein the following year. 6. Average maternal postpartum body composition was similar between the two colonies, but temporal patterns differed at one colony where pup production was decreasing from another where pup production was increasing. Mothers at the declining colony consistently weaned larger pups than mothers at the increasing colony across the range of mother sizes, but measures of maternal body composition did not predict pup weaning masses. Postprint

Background Gastroschisis is a congenital anomaly of the abdomen in which the intestines are found outside of the body at birth. While no clear causative factors have been identified, it is strongly associated with young maternal age. Other reported associations include low maternal socioeconomic status, low maternal body mass index (BMI), and smoking. Methods This is a retrospective review of epidemiologic data relating to cases of gastroschisis in Ontario from 2012-2018 in the Better Outcomes Registry & Network (BORN) Ontario database, which is the province's prescribed maternal-newborn registry. We describe the epidemiology of gastroschisis in Ontario with respect to birth prevalence, maternal age, health, exposures, and geography. Results The birth prevalence of gastroschisis is 2.31 cases/10,000 births. There was no apparent change in birth prevalence over the study period and there was no difference between male and female infants. Gastroschisis was associated with younger maternal ages and was inversely correlated with maternal BMI. Gastroschisis was associated with first completed pregnancy. Maternal diabetes was associated with a lower birth prevalence of gastroschisis than average. Mothers of babies with gastroschsis were more likely to report use of tobacco, alcohol, and drugs during pregnancy than those without gastroschisis, with marijuana use showing the largest increase in birth prevalence of gastroschisis. Mothers living in rural areas were more likely to have a baby with gastroschisis than those in urban centers, even after controlling for maternal age. Conclusions This Ontario registry study reveals that mothers with babies with gastroschisis are more likely to be young and thin, live in rural areas, and report prenatal smoking, alcohol use, and drug use than women whose pregnancies do not have gastroschsis.

Background Bariatric procedures are on the rise. The risk of birth defects in pregnancies following such procedures may be increased (eg, due to nutrient deficiencies) or decreased (eg, due to decreased maternal body mass index, BMI). Methods We conducted a systematic literature review of the association between bariatric surgery and birth defects using Ovid MEDLINE and PubMed (1946-2017). Information was abstracted on study design, exposures, outcomes, covariates and estimates of association. Results Fifteen studies met our inclusion criteria: 14 evaluated the outcome of any birth defect, and one evaluated neural tube defects. Estimates of association between bariatric surgery and birth defects were available for nine studies and ranged from 0.6 to 1.9 (all 95% confidence intervals included 1.0). When studies were stratified by surgery type, there was no obvious pattern of association. When stratified by the approach used to account for BMI, positive associations were observed in studies that did not account for maternal prepregnancy BMI or used women with normal BMI as the reference group (range: 1.3-1.9). Estimates from studies that either matched or adjusted for prepregnancy BMI were closer to the null (range: 1.1-1.2) and studies that compared to morbidly obese women reported protective associations (range: 0.6-0.7). Conclusions Studies of the association between bariatric surgery and birth defects vary with respect to the surgical procedures included, birth defects ascertainment methods and approaches used to account for maternal BMI. Consequently, it is not possible to draw a conclusion regarding the association between bariatric surgery and birth defects. Additional studies are warranted.

BACKGROUND Reliability of noninvasive prenatal RHD genotype test (NIP RHD) depends on having sufficient amounts of cell-free fetal DNA (cffDNA) in the maternal plasma sample. The fraction of cffDNA in maternal plasma is inversely related to maternal body mass index (BMI), suggesting that high maternal BMI may limit the test's accuracy. This study determined the effect of maternal BMI on the accuracy of NIP RHD. STUDY DESIGN AND METHODS Results from NIP RHD performed in Gestation Week 25 were correlated to maternal BMI in Week 12. The accuracy of NIP RHD result was determined by correlation with serologic RhD types of the neonates. RESULTS A total of 1618 pregnancies in 1588 D- women were included. Median BMI in these pregnancies was 24.2 (10%-90%, 20.1-32.4), and in 261 of 1618 (16%) pregnancies BMI was 30 or more (median BMI in this group was 33.6; 10th-90th percentiles, 30.5-41.1). NIP RHD was positive in 987 of 1618 (61%), negative in 582 of 1618 (36%), and inconclusive in 49 of 1618 (3.0%). Compared to the neonate's serologic RhD type, nine of 987 (0.9%) positive NIP RHD results were false positive, and four of 582 (0.7%) negative NIP RHD results were false negative (FN). In five of 49 (10%) inconclusive NIP RHD results, the neonatal RhD type was positive. There was no difference in median BMI between individuals who tested inconclusive or FN compared to those with true positive or true negative results (p = 0.80). CONCLUSION The accuracy of NIP RHD testing performed in Gestation Week 25 does not depend on maternal BMI in the 12th gestation week.

Objective To evaluate the impact of maternal body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters) on labor progress in nulliparous women. Methods The present prospective cohort study enrolled primigravidae admitted to Kasr Al Ainy hospital, Cairo University, Egypt, during active labor between February 1, 2016, and February 28, 2017. Patients were classified into three equal groups using their BMI at admission: underweight (

The level of parental investment in free-living offspring varies greatly within and among vertebrate taxa, and the mechanisms that mediate investment are likely targets of selection in the evolution of reproductive strategies. In mammalian and avian systems, individual investment is adjusted according to parental energetic status, and regulatory mechanisms have been described. Parental care is also a component of the life history of several groups of squamates and archosaurs, but little to nothing is known regarding the mechanisms that underlie individual variation in parental investment in these groups. Therefore, we examined the relationships among maternal body condition, corticosterone, arginine vasotocin (AVT), and maternal care in postparturient pigmy rattlesnakes. Energetic status was manipulated in pregnant females by supplemental feeding, and AVT was manipulated in postparturient mothers by intraperitoneal injection. Circulating corticosterone and body condition were recorded in postparturient mothers. Mother-offspring spatial relationships were analyzed to determine the closeness of mother-offspring associations. No significant relationship between maternal body condition and baseline corticosterone was observed in mothers, and no significant relationship was found between corticosterone and the level of maternal association with offspring. Manipulation of AVT did not stimulate maternal care. There was a strong and repeatable positive relationship between maternal postparturient body condition and the level of maternal association with offspring. The lack of a significant correlation between body condition and corticosterone does not support the hypothesis that a postparturient glucocorticoid response drives the observed condition-dependence of maternal offspring association.

Purpose: We generate 12 models from 4 pregnant individuals to evaluate individual differences in local specific absorption rate (SAR) for differing body habitus and fetal and maternal positions. Methods: Structural MR images from 4 pregnant subjects (including supine and left-lateral maternal positions) were manually segmented to create 12 body models by rotating the fetus, modifying the fat content, and altering the maternal arm position in 1 of the subjects. Electromagnetic simulations modeled at 3 Tesla determined the average and peak local SAR in the maternal trunk, fetus, fetal brain, and amniotic fluid. Results: We observed a significant range of fetal and maternal peak local SAR across the models (maternal trunk: 19.14-44.03 watts/kg, fetus: 9.93-18.79 watts/kg, fetal brain 3.36-10.3 watts/kg). We found that maternal body habitus changes introduced a significant variation in the maternal peak local SAR but not the fetal local SAR. However, the maternal position (either rotating the mother to left–lateral position or altering the arm position) introduced changes in fetal peak local SAR (range: 11.9-17.9 watts/kg). Rotating the fetus also introduced variation in the fetal and fetal brain peak local SAR. Conclusion: The observed variation in SAR emphasizes the need for more anatomical models to enable better safety management of individuals during fetal MRI, including a wider range of gestational ages., National Institutes of Health (Grants U01 HD087211, R01 EB017337)

Objectives There have been several attempts to classify cause of death (CoD) in stillbirth; however, all such systems are subjective, allowing for observer bias and making comparisons between systems challenging. This study aimed to examine factors relating to determination of CoD using a large dataset from two specialist centers in which observer bias had been reduced by classifying findings objectively and assigning CoD based on predetermined criteria. Methods Detailed autopsy reports from intrauterine deaths in the second and third trimesters during 2005–2013 were reviewed and findings entered into a specially designed database, in which CoD was assigned using predefined objective criteria. Data regarding CoD categories and factors affecting determination of CoD were examined. Results There were 1064 intrauterine deaths, including 246 early intrauterine fetal deaths (IUFD) (< 20 weeks), 179 late IUFDs (20–23 weeks) and 639 stillbirths (≥ 24 weeks' gestation). Overall, around 40% (n = 412) had a clear CoD identified, whilst around 60% (n = 652) were classified as ‘unexplained’, including around half with identified risk factors or lesions of uncertain significance, with the remaining half (n = 292 (45%)) being entirely unexplained. A stepwise increase in the proportion of unexplained deaths was observed with increasing maceration. Black and Asian women had significantly greater proportions of deaths due to ascending infection, whilst women aged over 40 years had significantly increased placenta-related CoDs. There was no significant difference in CoD distribution according to maternal body mass index or with increasing postmortem interval. Around half of those with an identifiable CoD could be identified from clinical review and external fetal examination or imaging, with most of the remainder being determined following placental examination. Conclusions Based on objective criteria, many intrauterine deaths throughout gestation remain unexplained despite autopsy examination. The rate of unexplained death varies from around 30% to 60% depending on interpretation of the significance of features. CoD determination is dependent on both the classification system used and subjective interpretation, such that variation in the proportion of ‘unexplained’ cases is based largely on speculation regarding mechanisms of death. Novel methods to determine objectively the mechanism of death at postmortem examination are required. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Female yellow perch Perca flavescens exposed to three overwinter temperature regimes (4, 8 and 13° C) for 150 days spawned in markedly different proportions upon spring warming (37% of females in 4° C v. 64 and 91% in 8 and 13° C treatments, respectively), but exhibited no differences in fecundity, egg size or egg lipid content. Females held at 4° C also exhibited less within-clutch egg size variation than females held at 13° C. Moreover, eggs differed among temperature treatments in the overall proportions of 18 fatty acids, with the colder treatments resulting in potentially higher quality eggs containing more of the unsaturated fatty acids C16:1, C22:6-n3 and C18:2 cis. Female somatic condition also varied with temperature. Maternal somatic growth and protein content increased while lipid content decreased in 13° C compared to the colder treatments. There were, however, no differences among treatments in the fatty acid composition of maternal muscle. These results suggest that the temperatures experienced during winter may be less influential to P. flavescens egg size or number, which may exhibit relatively little plasticity in this species, but can alter both the number of females that spawn and the overall composition of eggs and maternal somatic tissues, which may have implications for future reproductive success.

Aim To investigate the possible effect of maternal obesity on the accuracy of sonographically estimated fetal weight in the third-trimester shortly before induction of labor and to compare the accuracy of the estimation between normal weight, overweight, and class I, class II and class III obese groups. Methods This was a prospective study of singleton pregnancies with sonographic fetal weight estimation prior to scheduled delivery. Women were classified according to current body mass index (BMI) into five categories: normal (BMI 18.5–24.9 kg/m2, n = 41), overweight (BMI 25.0–29.9 kg/m2, n = 44), obese class I (BMI 30.0–34.9 kg/m2, n = 40), obese class II (BMI, 35.0–39.9 kg/m2, n = 38) and obese class III (BMI ≥ 40.0 kg/m2, n = 35). The estimated fetal weight was compared with the actual birthweight, and the difference between them was recorded as the error. Results Mean absolute error of sonographic fetal weight estimation was 106.97 ± 80.83 g, 198.88 ± 124.32 g, 248.82 ± 122.75 g, 308.31 ± 138.97 g and 446.00 ± 151.46 g in the normal, overweight, obese class I, obese class II, and obese class III groups, respectively (P < 0.001). The corresponding mean absolute percentage errors were 3.51 ± 2.76, 6.37 ± 3.91, 7.93 ± 4.81, 9.87 ± 4.32 and 14.06 ± 5.83 (P < 0.001). Conclusions Maternal obesity decreases the accuracy of sonographic fetal weight estimation. Clinicians should be aware of the limitations of sonographic fetal weight estimation, especially in obese patients.

Mother-to-child transmission (MTCT) of HBV is responsible for approximately half of the HBV transmission routes and continues to be a challenging problem worldwide. Even after the development of effective vaccines and clear World Health Organization guidelines toward HBV several decades ago, 1-9% newborns of HBV-carrying mothers still acquire HBV in early life as a result of in utero infection. The prevention of MTCT is of high importance, because chronically infected individuals function as a reserve for sustained HBV transmission, and 25% of them can develop asymptomatic liver cirrhosis and hepatocellular carcinoma. In this article, we review the canonical and novel HBV infection routes/mechanisms, influencing factors, diagnostic criteria, and interruption strategies for HBV MTCT. The preventative strategy of HBV MTCT has evolved from routine postpartum HB immune globulin (HBIG) plus HB vaccine schedules to administration of HBIG or nucleoside analogs during pregnancy and minimizing the exposure of maternal body fluids to the newborn during delivery.

SummaryBackground Leptin concentrations increase throughout pregnancy but little is known about factors that influence this physiological change and whether they differ according to pregestational body mass index (BMI). Objective To assess whether longitudinal trends of leptin in pregnancy are influenced by biochemical, anthropometric and lifestyle factors in women with normal weight (NW), overweight (OW) or obese (OB) pregestational BMI. Design and methods Prospective cohort of 232 pregnant women followed at 5–13th, 20–26th and 30–36th gestational weeks. The effect of selected variables on longitudinal behaviour of plasma leptin concentrations, stratifying for NW (18·5–24·9 kg/m2), OW (25–29·9 kg/m2) and OB (≥30·0 kg/m2) pregestational BMI was assessed through longitudinal linear mixed-effects models. Results The multiple regression model for women with NW revealed associations of maternal body weight (β = 0·714, CI = 0·491 to 0·937), serum HDL-cholesterol (β = 0·239, CI =0·089 to 0·388) and C-reactive protein (CRP) (β = −0·138, CI = −0·272 to −0·004) with plasma leptin concentrations. Maternal body weight (β = −0·871, CI = 0·475 to 1·267) and serum HDL-cholesterol concentrations (β = 0·315, CI = −0·022 to 0·651) were also associated with leptin in OW women. In OB women, serum HDL-cholesterol (β = 0·722, CI = 0·219 to 1·226), maternal body weight (β = 0·666, CI = 0·187 to 1·145), triglycerides concentrations (β = −0·130, CI = −0·241 to −0·020) and dietary carbohydrate (β = 0·075, CI = 0·023 to 0·126) were significantly associated with plasma leptin. Conclusion Maternal body weight and serum concentrations of HDL-cholesterol were associated with leptin changes independent of pregestational BMI. Serum CRP concentrations were associated with leptin only in NW women and serum triglycerides concentrations and dietary carbohydrate only in OB. These results indicate that factors that influence leptin concentrations differ according to pregestational BMI.

Purpose To determine the effect of maternal body mass index on fetal growth using individualized growth assessment and two-level linear modeling. Methods A retrospective review of biometry in the second and third trimesters from 246 normal, term singleton fetuses was performed. Four to eight biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur diaphysis length (FDL) measurements per fetus were available and used to determine second-trimester growth rates. Expected third-trimester size trajectories were generated from these data and Percent Deviations [%Dev = ((observed − expected)/expected) × 100] were calculated. Two-level linear modeling was used to determine %Dev slopes and the effect of body mass index (BMI) on these slopes. Relationships between individual second- and third-trimester slopes and BMI were evaluated using linear regression. Results Linear regression analysis of second-trimester growth indicated no significant relationships between the fetal growth rate and the BMI in the second trimester [R2 (adj): 0.0% to 1.0% except AC in one subgroup (5.6%)]. Regression analysis did not indicate a significant relationship (adj R2: 0%–0.2%) between BMI and third-trimester %Dev slopes for any anatomic parameter. Two-level statistical modeling showed no effect of BMI on BPD, AC, or FDL growth and only a moderate effect on the HC growth in the third trimester. Conclusions Our findings indicate that the maternal BMI does not have an effect on fetal growth in either the second or the third trimester as determined with individualized growth assessment. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 42:456–464, 2014

Summary 1. Animals that show indeterminate growth and put relatively constant proportions of stored body reserves towards annual reproductive effort are confronted with a problem of meeting ever-increasing energetic demands in unpredictable environments. 2. We examined how intrinsic traits, mass and age, as well as extrinsic environmental features impact diving and movement behaviour in a marine capital breeder, the northern elephant seal, Mirounga angustirostris. We assessed the impact of this behavioural variation on foraging success, measured as energy gained at sea. 3. We used principal component analysis to reduce behavioural variables into three principal components that described time in foraging zones (PC1), foraging distance (PC2) and bout structure of dive shapes (PC3). 4. Both intrinsic traits and extrinsic environmental features influenced behaviour and foraging success. Body mass was the sole predictor of residence time in foraging zones (PC1), which, in turn, was the strongest behavioural predictor of foraging efficiency and success over the short postbreeding season. Foraging distance (PC2) significantly varied with year. Since foraging distance is an index of the horizontal and vertical distances seals travel while foraging, we suggest that it was impacted by inter-annual variation in marine prey distribution. Age had a negligible impact on most aspects of behaviour, except for the structure of dive shapes on the postmoult foraging trip. 5. All principal components significantly impacted rates of energy gain for postbreeding foraging trips when maternal body stores must be recovered quickly before returning to shore to moult. Age impacted the bout structure of dives in pregnant females in a way that influenced success, suggesting a role for previous experience during the long postmoult foraging migration. 6. Strong impacts of body mass on diving ability, foraging success and reproductive effort suggest a proximate mechanism for trade-offs in the cost of reproduction. Mass lost to current investment in offspring impacts a mother’s ability to accrue resources for future offspring.

OBJECTIVES Initial screening sonography of the fetal heart with static images is often inadequate, resulting in repeated imaging or failure to detect abnormalities. We hypothesized that the addition of short cine clips would reduce the need for repeated imaging. METHODS Two-dimensional (2D) static sonograms and short 2D cine clips of the 4-chamber view and left and right ventricular outflow tracts were obtained from 342 patients with gestational ages of greater than 16 weeks. A diagnostic radiologist and a perinatologist retrospectively reviewed the static and cine images independently and graded them as normal, abnormal, or suboptimal. RESULTS A statistically significant increase in the number of structures called normal was seen when 2D cine clips were added to static imaging for both observers (P < .05); the radiologist called 86.5% normal with combined static and cine images versus 61.9% with static images alone, whereas the perinatologist recorded 68.1% as normal versus 58.8%, respectively. The radiologist called 77.8% of structures normal with cine images only versus 61.9% with static images only (P < .001), whereas the perinatologist called fewer structures normal with cine images alone (38.9%) versus static images alone (58.8%). The use of cine loops alone resulted in no significant increase in the ability to clear the heart as normal. The maternal body mass index was inversely associated with the ability to clear structures when 2D cine images were added to static images (P < .05). CONCLUSIONS The addition of 2D cine clips to standard 2D static imaging of the fetal heart significantly improves the number of structures cleared as normal. Two-dimensional cine clips are easily obtained, add little time to a study, and require minimal archival space.

We investigated the independent effects of age at smolting and body condition at the time of spawning on egg production by female Atlantic salmon (Salmo salar). For a given body size, female salmon that had smolted as juveniles after 2 years in fresh water produced smaller, more numerous eggs than females that smolted 1 year later. Furthermore, fecundity (but not egg size) was related positively to maternal body condition at spawning. Given that age at smolting is closely related to juvenile growth rate; results from this study suggest that conditions experienced by female Atlantic salmon during both early life and adulthood have implications for the size and number of eggs that they produce.

Aim: This study compared the diets of breastfeeding and non-breastfeeding mothers from socioeconomically diverse regions of Melbourne to determine whether breastfeeding is a marker for healthier maternal dietary intakes. Methods: This cross-sectional study obtained information via self-reported questionnaire from 529 first-time Melbourne mothers. Breastfeeding status was determined when the children were 3.9 months. Diet information was obtained using a validated Food Frequency Questionnaire. Maternal diet was assessed by seven indicators: average daily intake of fruit, vegetables, non-core drinks, non-core sweet snacks, non-core savoury snacks, variety of fruit and variety of vegetables eaten in the preceding 12 months. Associations between breastfeeding status and each dietary variable were assessed using linear regression analyses. Socioeconomic position, maternal body mass index and the cluster-based sampling design were controlled for. Results: Of the 529 subjects, 70% were breastfeeding their child. Compared with non-breastfeeding mothers, breastfeeding mothers were found to consume more serves of vegetables (P= 0.001), a greater variety of fruit and vegetables (P= 0.001 and P≤ 0.001 respectively), and sweet snacks were consumed more frequently (P= 0.006). Differences were observed between low and high socioeconomic position mothers for fruit serves (P= 0.003), vegetable serves (P= 0.010) and fruit variety (P= 0.006). These associations persisted after controlling for socioeconomic position and maternal body mass index. Conclusions: The association between infant feeding (breastfeeding) and some aspects of maternal diet provides further evidence suggesting a link between maternal and child diets from a younger age than previously examined.

To determine the incidence and trends of gestational diabetes mellitus (GDM) in Bahrain from 2002 to 2010, and to investigate 2 possible risk factors within the affected population.In a retrospective survey, data on maternal body weight and age were collected from women who gave birth in government maternity units in Bahrain and who were screened for GDM during pregnancy using the 2-step approach and criteria of the US Expert Committee on the diagnosis and classification of diabetes.Among 49 552 pregnant women, 4982 (10.1%) were diagnosed with gestational diabetes. The Cox-Stuart test for trend analysis suggested that there was an increase in the incidence of gestational diabetes from 7.2% in 2002 to 12.5% in 2010 (P0.01). For the period 2006-2010, maternal age, and weight at onset of pregnancy and at time of delivery were positively associated with risk of GDM with an odds ratio (95% confidence interval) of 1.094 (1.081-1.107), 1.081 (1.001-1.104), and 1.027 (1.013-1.040), respectively.A combination of increasing maternal weight, maternal age, and incidence of GDM among women in Bahrain indicates a significant future burden on health services.

Objective To prospectively assess the contribution of a high-frequency linear transducer and of moving target indicator (MTI) filtered color flow mapping in the visualization of cardiac fetal anatomy at the routine 11 to 13 + 6-week scan. Methods This was a cross-sectional prospective study, including 300 singleton fetuses at 11 to 13 + 6 weeks' gestation. Patients were randomized into four groups and a detailed fetal cardiac examination was conducted transabdominally using either a conventional curvilinear transducer, a conventional curvilinear transducer and MTI filtered color flow mapping, a high-frequency linear transducer or a high-frequency linear transducer and MTI filtered color flow mapping. Regression analysis was used to investigate the effect on the ability to visualize different cardiac structures of the following parameters: gestational age at ultrasound examination; fetal crown–rump length (CRL); maternal body mass index (BMI); transducer–heart distance; the technique used at ultrasound; and the position of the placenta. Results The four-chamber view was visualized in 89.0% of fetuses and regression analysis showed this rate was correlated with CRL and the use of MTI filtered color flow mapping during ultrasonography, and inversely correlated with BMI and transducer–heart distance. Use of a conventional curvilinear transducer and MTI filtered color flow mapping allowed visualization of the four-chamber view in 97.3% of fetuses, while this was only possible in 84.0% of fetuses using a high-frequency linear transducer. The left and right outflow tracts were visualized in 62.3 and 57.7% of fetuses, respectively. Regression analysis showed that the ability to visualize the left or the right outflow tract was correlated with the use of MTI filtered color flow mapping during scanning and was inversely correlated with transducer–heart distance. The use of a conventional curvilinear transducer and MTI filtered color flow mapping allowed visualization of the left and right outflow tracts in 96.0 and 97.3% of fetuses, respectively, while this was only possible in 37.3 and 26.7% of fetuses using a high-frequency linear transducer. Conclusions During the routine 11 to 13 + 6-week scan, the use of MTI filtered color flow mapping but not of a high-frequency linear transducer, improves visualization of cardiac anatomy. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

Among temperate-breeding birds, offspring survival and reproductive success are often inversely related to timing of breeding. The mechanisms that produce seasonal declines in offspring survival are not fully understood but may be related to temporal changes in parental quality, environmental quality, or both. We analyzed data for lesser scaup Aythya affinis to evaluate hypothesized effects of parental quality and date on pre-fledging survival. Maternal quality, as indexed by body mass, did not have an independent effect on offspring survival in this species. Maternal body mass did not decline seasonally and did not have an independent effect on duckling survival. Although we did not detect an independent effect of hatch date on duckling survival, duckling survival declined seasonally for broods raised by lightweight females, indicating an interactive effect of maternal mass and date. We hypothesize that this interaction may be driven by seasonally declining food resources coupled with the influence of female condition on the ability to monopolize food resources or remain attentive to the brood. We also tested morphological predictions of the date hypothesis by examining physical characteristics of ducklings. When corrected for age and size, late-hatched ducklings tended to have marginally larger digestive systems and smaller leg muscles than did early-hatched birds. Abundances of intestinal parasites acquired through diet decreased marginally in late-hatched ducklings. Results for digestive system and parasite infection patterns suggested that later-hatched broods may shift diets, consistent with a contribution of environmental factors to seasonal variation in offspring survival. Taken together, our results suggest that both female attributes and environmental conditions may influence seasonal patterns of offspring survival in this species.

We present a phylogenetic comparative study assessing the evolutionary determinants of egg size in the moth family Geometridae. These moths were found to show a strong negative allometric relationship between egg size and maternal body size. Using recently developed comparative methods based on an Ornstein-Uhlenbeck process, we show that maternal body size explains over half the variation in egg size. However, other determinants are less clear: ecological factors, previously hypothesized to affect egg size, were not found to have a considerable influence in the Geometridae. The limited role of such third factors suggests a direct causal link between egg size and body size rather than an indirect correlation mediated by some ecological factors. Notably, no large geometrid species lay small eggs. This pattern suggests that maternal body size poses a physical constraint on egg size, but within these limits, there appears to be a rather invariable selection for larger eggs.

Aim: To identify variables which are strongly associated with fetal growth. Material and Methods: The study subjects were 203 Japanese women who had a plasma glucose level ≥140 mg/dL (7.8 mmol/L) on a 50-g glucose challenge test but were normoglycemic when challenged with a 75-g oral glucose tolerance test (GTT) according to the criteria previously used in Japan. All the subjects subsequently gave birth to singleton infants. The correlations between the standard deviation for birthweight (birthweight SD) and 15 other variables, including the maternal body mass index (BMI), plasma levels of glucose and insulin on the GTT, and various indices calculated using data from the GTT, were then examined. Univariate and multivariate regression analyses were performed. Results: Univariate analyses revealed significant correlations between the birthweight SD and the fasting plasma glucose level (P = 0.0063), the pre-pregnancy BMI (P = 0.0001), and the BMI at delivery (P

1. The metabolic theory of ecology (MTE) predicts that, after correcting for body mass variation among organisms, the rates of most biological processes will vary as a universal function of temperature. However, empirical support for 'universal temperature dependence' (UTD) is currently equivocal and based on studies of a limited number of traits. 2. In many ectothermic animals, the rate at which females produce mature eggs is temperature dependent and may be an important factor in determining the costs of reproduction. 3. We tested whether the rate of egg maturation in marine turtles varies with environmental temperature as predicted by MTE, using the time separating successive clutches of individual females to estimate the rate at which eggs are formed. We also assessed the phenotypic contribution to this rate, by using radio telemetry to make repeated measurements of interclutch intervals for individual green turtles (Chelonia mydas). 4. Rates of egg maturation increased with seasonally increasing water temperatures in radio-tracked green turtles, but were not repeatable for individual females, and did not vary according to maternal body size or reproductive investment (number and size of eggs produced). 5. Using a collated data set from several different populations and species of marine turtles, we then show that a single relationship with water temperature explains most of the variation in egg maturation rates, with a slope that is statistically indistinguishable from the UTD predicted by MTE. However, several alternative statistical models also described the relationship between temperature and egg maturation rates equally parsimoniously. 6. Our results offer novel support for the MTE's predicted UTD of biological rates, although the underlying mechanisms require further study. The strong temperature dependence of egg maturation combined with the apparently weak phenotypic contribution to this rate has interesting behavioural implications in ectothermic animals. We suggest that maternal thermoregulatory behaviour in marine turtles, and many other reptiles, is consistent with a strategy of adaptively increasing body temperatures to accelerate egg maturation.

Objective To investigate the existence of a relationship between maternal body mass, maternal ethnicity and maternal smoking status and nuchal translucency (NT) in the first trimester of pregnancy. Methods NT measurements from 130 339 euploid, singleton pregnancies were converted to NT multiples of the median (MoM) and delta NT using expected medians determined using regression analysis. Relationships between maternal body mass index (BMI), maternal weight, maternal ethnicity and maternal smoking status and NT MoM and delta NT were examined. Results NT increased with gestational age. Uncorrected NT MoM and delta NT demonstrated small but significant positive relationships with either maternal BMI or maternal weight. Both NT MoM and delta NT were slightly, but significantly, increased in smokers compared to non-smokers and Afro-Caribbean compared to Caucasians, and slightly, but significantly, decreased in Asians compared to Caucasians. Conclusion Although statistically significant, all the changes reported are likely to be too small to be relevant in terms of correcting in prenatal screening. Copyright © 2011 John Wiley & Sons, Ltd.

This paper comprehensively reviews transdisciplinary and critical perspectives on the employed maternal (pregnant and post-birth) body in the context of management studies. It highlights the disparities between equal opportunities policies and everyday management practices in relation to pregnancy and new motherhood. In so doing, the review examines the contradictions between equal opportunities policies aimed at protecting pregnant and newly maternal employees and the discouraging treatment that such women receive in practice at work. In analysing the disparity between policy and practice, the review identifies gaps within the field of research on the employed maternal body. It then shows how perceptions about the pregnant and newly maternal body are based more on myth than on evidence. In keeping with policies encouraging family friendly working practices and aimed at enhancing parental health, the paper argues that research on the maternal body is integral to management studies.

Summary Reasons for performing study: An opportunity to monitor equine chorionic gonadotrophin (eCG) production during 61 pregnancies in 25 Thoroughbred mares mated to the same Thoroughbred stallion was utilised in order to further knowledge regarding factors involved in the production of this hormone. Objectives: To examine the effects of maternal body condition, exercise and parity on eCG production. Methods: In the first experiment, maiden mares were fed either a moderate (n = 9) or an excessive (n = 10) food intake throughout gestation. In the second experiment, 5 mares were exercised daily during pregnancy and eCG production rates were compared to 5 nonexercised mares. In the third experiment, eCG profiles were compared in 9 mares during 3 successive pregnancies. Equine chorionic gonadotrophin secretion was assessed as area under the curve (AUC), peak serum concentration, timing of the peak and the rate of decline. In addition, a mean eCG profile of 61 pregnancies was created to provide means and ranges for the above parameters. Results: In Experiment 1, eCG production was significantly higher in moderately rather than excessively fed mares in terms of AUC and peak eCG concentrations. In Experiment 2, the mean AUC did not differ between exercised and nonexercised animals but mean eCG concentrations were significantly higher in nonexercised mares between Days 60 and 90 of gestation. In Experiment 3, eCG became undetectable significantly earlier in gestation in the third parity. The mean eCG profile of 61 pregnancies showed a peak of 64.5 ± 3.7 iu/ml at 62.4 ± 1.0 days after ovulation and was undetectable by 134.1 ± 1.7 days. Peak eCG levels reduced by 50% 22.6 ± 1.13 days. Conclusions: Some of the factors examined clearly influenced eCG production rate, the secretion of this hormone and its rate of disappearance from the blood. Potential relevance: The results provide insights into some factors that govern the production of the placental gonadotrophin, eCG.

Prenatal risk ratios for Down syndrome adjust for maternal weight because maternal serum 2 biomarker levels decrease with increasing maternal weight. This is accomplished by converting 3 serum biomarker values into a multiple of the expected median (MOM) for women of the same 4 gestational age. Weight is frequently not recorded and the impact of using MOMs not adjusted for 5 weight for calculating risk ratios is unknown. The aim of this study is to examine the effect of 6 missing weight on first trimester Down syndrome risk ratios by comparing risk ratios calculated 7 using weight-unadjusted-and –adjusted MOMs. Findings at the population level indicate that the 8 impact of not adjusting for maternal weight on first trimester screening results for chromosomal 9 anomalies would lead to under-identification of 84 per 10,000 pregnancies. NHMRC

Objectives The purpose of this study was to determine if prenatal exercise alters the maternal and fetal heart responses during labor and delivery. We hypothesized that fetuses of exercising mothers would exhibit a lower baseline heart rate (HR), increased HR variability (HRV), and no differences in fetal heart accelerations and decelerations. Design This study employed a cross‐sectional design. Methods The Modifiable Physical Activity Questionnaire was used for group classification. Exercising women were those participating in 30 minutes of moderate‐to‐vigorous exercise at least 3×/week throughout the entire pregnancy. Women achieving a lower dose of exercise were classified as non‐exercisers. Cardiotocography recordings during the first hour of labor and delivery assessed fetal baseline HR, HRV, accelerations, decelerations, and contractions. ANCOVA analyses were performed to assess group differences in these outcomes and were adjusted for maternal body mass index. Results Thirty‐one women were included in the analyses. No group mean differences were found for maternal and fetal characteristics, except for maternal age (EX: mean (SD) 28.5 (±4.6y) vs NON‐EX: 24.1 (±1.2y)). After controlling for body mass index, no statistical differences in maternal HR response (β = 3.9, SE = 5.0, 95%CI −6.4‐14.2) or fetal HR response (β = 3.9, SE = 2.5, 95%CI −1.2‐9.11), accelerations and decelerations (β= −0.03, SE = 0.4, 95%CI −0.9‐0.8; β= −0.10, SE = 0.4, 95%CI −0.8‐0.9, respectively), or HRV (β = 0.6, SE = 1.7, 95%CI −2.8‐4.0) were observed. Conclusions Based on the findings of this study, we found no evidence that maternal exercise during pregnancy was associated with maternal or fetal HR response during labor and delivery. These data suggest maternal exercise may not elicit positive or negative effects on maternal and fetal cardiovascular responses to the physiological stress of labor and delivery.

Our understanding of snake biology is heavily biased towards species and populations occurring at higher latitudes. In particular, little information is available concerning the biology of the numerous species of Mexican rattlesnakes. We studied the reproductive ecology of female Mexican lance-headed rattlesnakes Crotalus polystictus in a montane (c. 2500 m a.s.l.) valley of the Rio Lerma, in the Mexican state of Mexico. We collected data from 162 different females and 203 litters over 4 years (2004–2007). Parturition coincided with summer monsoon rains, with the majority of females giving birth in late June and early July. Larger females and females gestating larger litters typically gave birth earlier in the summer than did smaller females and females gestating smaller litters. Some females matured rapidly; 26 females reproduced as 3-year olds, 17 as 2-year olds and a single female reproduced at 1 year of age. Females commonly reproduced in consecutive years. Litter size and mean neonate size increased with maternal body length; however, the relative clutch mass did not vary with female size. The mean litter size was 7.3 neonates (range 3–15), and the mean neonate body length (snout–vent length) and mass were 198 mm and 8.7 g. Neonate size varied less than did other litter characteristics. Rapid maturity, frequent reproduction and synchronization of parturition with seasonal precipitation are consistent with previously observed patterns of snake reproduction at lower latitudes.

1. The main reproductive parameters of exotic Trachemys scripta elegans in established populations from two ponds in southern Spain are described. 2. Females were found to reproduce at 5 years of age, although sexually mature individuals of 4 and 3 years of age were also detected. Annual reproductive frequency was estimated to be 80-86% of reproductive females. Mean clutch size was 11.5 eggs and was not correlated with maternal body size. 3. The number of follicles of different size in ovaries suggested that four or more clutches could be laid per season. Eggs were laid from April to June (inclusive) mainly during morning hours, when females were easily detected during nesting trips. 79.5% of eggs were fertile. 4. Reproductive parameters of this species in southern Spain were of similar or even higher values than in native areas, thus placing them among chelonian species of earlier maturity. 5. Although chelonians might never be considered explosive breeders, the number of T. s. elegans individuals could surpass that of native aquatic chelonians in southern Spain, where T. s. elegans reach maturity earlier, are more fecund and their eggs are more fertile. Copyright © 2008 John Wiley & Sons, Ltd.

Recent studies have found age-specific variations in reproductive performance amongst Weddell seals, Leptonychotes weddellii, and we hypothesized age-related variations in maternal body mass as a mechanism linking maternal age and the observed patterns of reproductive performance. We evaluated the effects of maternal traits such as age and reproductive experience and the effects of environmental variations on maternal body mass at parturition. Maternal body mass at parturition showed substantial age- and environmental-related variations. Maternal body mass increased with age through the young and middle ages, and evidence of senescent declines in body mass was found amongst the oldest ages. Additionally, body mass at parturition was strongly influenced by environmental variations during the pregnancy period, specifically sea-ice extent and the state of the El-Nino Southern Oscillation. Patterns of age-specific variations in body mass were consistent with age-specific patterns of offspring survival probability, which supported our hypothesis that changes in body mass link maternal age and reproductive performance in the Weddell seal. Further, environmental conditions during pregnancy may be an important component of Weddell seal reproductive performance.

Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF), together simplified termed "dioxins", polychlorinated biphenyls (PCB), polybrominated diphenylethers (PBDE) and organochlorine pesticides constitute lipophilic, persistent organic pollutants that bioaccumulate in the food chain and consequently can be found in humans at considerable concentrations. During the past 30 years our institute analyzed far more than 2,000 individual human milk samples for organochlorine pesticides and PCB and over 1,000 specimens for PCDD/PCDF. The results of these analyses provide an overview and reliable basis as to contamination of human milk with these compounds, their correlations among each other, the temporal trend of exposure through breastfeeding and the predominant parameters that influence the maternal body burden. It was found that the levels of most persistent organohalogen compounds in human milk decreased significantly over the past three decades and equally did their exposure through breastfeeding. Exceptions are PBDE, which are still extensively used as flame-retardants. PBDE levels in milk samples collected in the early 2,000s are approximately 60% higher compared to specimens sampled 10 years before. Moreover, in contrast to PCB, PBDE show no significant correlation with PCDD/PCDF in human milk, which might be interpreted as an indication for another mode of human exposure.

Comparisons within and among populations offer important insights into variation in life-history traits and possible adaptive patterns to environmental conditions. We present the results of observed differences in body size, body shape and patterns of reproduction in four separate populations of the European pond turtle Emys orbicularis in central and southern Italy – coastal (n=3) and mountainous (n=1) sites and pond (n=2) and canal (n=2) habitats – to determine whether phenotypic plasticity affects reproductive output. Although we did not find any significant latitudinal variation in body size, we observed significant differences in body shape between canal (rounded body shape) and pond (elongated body shape) systems and smaller size with rounded shape in the mountainous population. Reproductive output is similar among populations (median=5 eggs per clutch), whereas reproductive investment (relative clutch mass to maternal body mass) is higher in the mountain population (one clutch per year) than in coastal populations (two clutches per year), suggesting differential trade-offs between geographic locality, elevation and habitat type. Turtle shell shape and geographic location together affect reproductive output in E. orbicularis in Italy.

Intra-individual variation can be extremely informative in understanding the evolution of life-history traits. In this study, we examined intra-individual variation in clutch and offspring size for brown house snakes Lamprophis fuliginosus, a species that can lay up to six clutches in the laboratory within a 12-month interval without a refractory period. The number of clutches produced per female during this interval ranged from two to six, and there was no significant relationship between the total number of clutches laid and maternal body size. Unlike results from lizards and turtles, house snakes showed no significant changes in clutch size or offspring size among successive clutches, and individual repeatability of both traits was moderate to high. House snakes in this study also showed a strong negative relationship between clutch size and offspring size for all clutches produced, as expected by life-history theory. Our data indicate that house snakes show much less intra-individual variation than most other reptile species examined. However, this high level of consistency may be due to regulation of food availability under laboratory conditions. This will be varied in future experiments to test the degree of plasticity exhibited by individual females for these traits.

Pinnipeds are a diverse group of aquatic carnivores that exhibit wide variation in body size, milk composition, lactation strategies, and the length of maternal care. We used 12 pinniped life-history and ecological traits to test hypotheses concerning the influence of phylogeny, maternal body size, breeding substrate, and other factors on the evolution of lactation strategies. We used independent contrasts to account for phylogenetic effects on correlations between traits. Our findings indicate that the negative relationships between maternal mass and lactation length and between maternal mass and the percentage of time spent at sea by females during lactation are not recent adaptations, but likely a result of phylogenetic history and an evolutionary grade shift in lactation length, which occurred when the phocids diverged from the otariids. Differences in body size between the ancestral phocid and otariid impacted their foraging strategies and metabolic rates, which subsequently influenced lactation strategies. The fat-storage abilities of large phocids may have allowed them to exploit remote and patchy prey resources and thereby reduce time spent feeding during lactation. We also suggest that an early divergence in the mammary gland structure of phocids and otariids is a fundamental influence on pinniped lactation strategies. Although estimates are lacking for several key species, body size appears to have little adaptive influence on the lactation length of extant species. Instead, an abbreviated lactation period seems to be adaptive in minimizing the relative milk energy expended over lactation, although it may have initially evolved to reduce maternal overhead, especially in ancestral fasting phocids. Subsequently, a brief lactation in phocids was also selected through the effects of terrestrial predation, the instability of breeding on pack-ice, and the energy benefits of increasing milk energy output.

The fetal heart rate is indispensable for monitoring the health of unborn cattle fetuses. To monitor the fetal heart rate, a method employing independent component analysis (ICA) to extract the fetal electrocardiogram (fECG) from potentials measured on the maternal body surface and composed of a mixture of the maternal ECG (mECG), fECG, baseline drift and noise is described. A mixing of the raw data was simplified using a linear time-invariant model. To separate the fECG from the mECG, baseline drift, and noise, an ICA strategy was applied, using a hyperbolic tangent as the contrast function and treating mutual information with the minimization principle to find the optimum demixing matrix to derive the fECG from the measured signals. After the feasibility of this method was shown on simulated signals obtained by randomly mixing pure fECG, pure mECG, low frequency sinusoidal drift and noise, real signals from three cloned pregnant Holstein cows with 157, 177 and 224-day gestation periods were used to verify the separation method. The results show that the fECG, mECG, low-frequency sinusoidal drift and noise can be clearly segregated in simulations, and that the fECG, mECG, baseline drift and noise can be successfully derived from real signals. The ICA approach has great potential in effectively detecting the fECG from maternal body surface potentials.

Many species exhibit skewed sex ratios at birth. Here we investigate the relationships between environmental and maternal variables (as surrogates for maternal condition) and foetal sex in African buffalo Syncerus caffer and elephant Loxodonta africana of the Kruger National Park, South Africa. Using logistic regression no significant effect was found of year, maternal lactational status, maternal age, rainfall or density on foetal sex ratio. Using a subset of our data, it was also concluded that maternal body condition did not affect foetal sex ratio in buffalo. Our analyses failed to support hypotheses predicting that mothers will skew the sex ratios of their offspring in relation to their body condition. In this study, buffalo and elephant produced offspring with a sex ratio close to parity. Our results are discussed in light of the implications for testing such hypotheses in analyses of population level.

BACKGROUND: Current recommendations for anti-D prophylaxis for women who deliver a D+ offspring vary from country to country, and the introduction of new reagents require pharmacokinetic studies that show serum levels after the injection. Serum levels of anti-D may depend on the maternal body mass index (BMI). STUDY DESIGN AND METHODS: Serum concen-trations of total anti-D IgG and IgG1-4 subclasses were determined by flow cytometry in 26 D– women, who had received prophylaxis after delivery of a D+ offspring. Blood samples were drawn on Days 1, 2, 3, and 14 after injection, and the BMI was recorded. RESULTS: Anti-D levels increased continuously in all women during the first 3 days. The increase was significantly affected by the BMI if higher than 27 kg per m2 (p < 0.001). The higher the BMI, the less was the increase of serum anti-D. Mean peak levels 72 hours after injection was 89 ng per mL in lean women, but estimated levels were 28 to 60 percent lower in women with a BMI of 28 to 40 kg per m2. The effect of a BMI higher than 27 kg per m2 on anti-D was not gradual but progressive. Similarly, the BMI affected serum concentrations of anti-D subclasses IgG1-4 (p < 0.001). CONCLUSION: The BMI needs consideration for the adjustment of the dosage of anti-D, provided its bio- availability to suppress alloimmunization is reflected by measurable amounts in the serum.