Difference In Gestation Length Research Articles

Exploring the seasonality of birth defects in the New York State Congenital Malformations Registry

Examining seasonal patterns of birth defects may help to identify environmental risk factors. Because the teratogenic window for most birth defects is during gestational weeks 3 to 8, investigating exposures closer to the timing of conception is important. However, studies are usually based on month of birth, which is not the biologically relevant exposure period and does not account for differences in gestational length. We aimed to determine whether the occurrence of birth defects varied by month of conception using the population-based New York State Congenital Malformations Registry (CMR). We merged live birth certificates (n = 2,044,091) with CMR records for mothers residing in New York State, excluding New York City, for the years 1992 through 2006. We categorized birth defects according to the National Birth Defects Prevention Network guidelines and performed Cochran-Armitage trend, Hewitt-Rogerson, and Walter-Elwood tests on month of conception and chi-square tests on season of conception. We graphed seasonal distributions and seasonality test results. We performed stratified analyses by maternal and infant characteristics. Of 42 groups examined in the 15-year period, 24 (57%) had at least one statistically significant test result, suggesting a trend or seasonal variation: Cochran-Armitage (18), Hewitt-Rogerson (17), Walter-Elwood (4), and chi-square (5). Ventricular septal defect showed the most consistent results: Cochran-Armitage (p = 0.0006), Hewitt-Rogerson (December to May; p = 0.0130), Walter-Elwood (March 14; p = 0.0027), and chi-square (winter; p = 0.0046). Congenital cataract, pulmonary valve atresia/stenosis, coarctation of aorta, biliary atresia, and renal agenesis or hypoplasia had at least three significant tests. These results may help to generate hypotheses about environmental factors that vary by season for further studies.

Associations of long interspersed nuclear element-1 DNA methylation with preterm birth in a prospective cohort study

Preterm birth affects over 12% of all infants born in the US yet the biology of early delivery remains unclear, including whether epigenetic mechanisms are involved. We examined associations of maternal and umbilical cord blood long interspersed nuclear element-1 (LINE-1) DNA methylation with length of gestation and odds of preterm birth in singleton pregnancies in Project Viva. In white blood cells from maternal blood during 1(st) trimester (n=914) and 2(nd) trimester (n=922), and from venous cord blood at delivery (n=557), we measured LINE-1 by pyrosequencing (expressed as %5 methyl cytosines within the LINE-1 region analyzed [%5mC]). We ran linear regression models to analyze differences in gestation length, and logistic models for odds of preterm birth (<37 v. ≥37 weeks gestation), across quartiles of LINE-1. Mean(SD) LINE-1 levels were 84.3(0.6), 84.5(0.4), and 84.6(0.7) %5mC for 1(st) trimester, 2(nd) trimester and cord blood, respectively. Mean(SD) gestational age was 39.5(1.8) weeks, and 6.5% of infants were born preterm. After adjustment for maternal age, race/ethnicity, BMI, education, smoking status, and fetal sex, women with the highest vs. lowest quartile of 1(st) trimester LINE-1 had longer gestations (0.45 weeks [95% CI 0.12, 0.78]) and lower odds of preterm birth (OR 0.40 [0.17, 0.94]), whereas associations with cord blood LINE-1 were in the opposite direction (-0.45 weeks, -0.83, -0.08) and (OR 4.55 [1.18, 17.5]). In conclusion, higher early pregnancy LINE-1 predicts lower risk of preterm birth. In contrast, preterm birth is associated with lower LINE-1 in cord blood.

Regional differences in surgical intervention following medical termination of pregnancy provided by telemedicine

Analysis of factors influencing surgical intervention rate after home medical termination of pregnancy (TOP) by women in countries without access to safe services using the telemedical service 'Women on Web'. Cohort study. Women with an unwanted pregnancy less than nine weeks pregnant who used the telemedicine service of Women on Web between February 2007 and September 2008 and provided follow-up information. Women who used medical TOP with a known follow up. Information from the online consultation, follow-up form and emails was used to analyze the outcome of the TOP. Ongoing pregnancy, reason for surgical intervention, perceived complications and satisfaction. Of the 2 323 women who did the medical TOP and had no ongoing pregnancy, 289 (12.4%) received a surgical intervention. High rates were found in Eastern Europe (14.8%), Latin America (14.4%) and Asia/Oceania (11.0%) and low rates in Western Europe (5.8%), the Middle East (4.7%) and Africa (6.1%; p=0.000). More interventions occurred with longer gestational age (p=0.000). Women without a surgical intervention more frequently reported satisfaction with the treatment (p=0.000). The large regional differences in the rates of reported surgical interventions after medical TOP provided by telemedicine cannot be explained by demographic factors or differences in gestational length. It is likely that these differences reflect different clinical practice and local guidelines on (incomplete) abortion rather than complications that genuinely needed surgical intervention. Surgical interventions significantly influenced womens' views on the acceptability of the TOP.

Is first-trimester crown-rump length associated with birthweight?

To evaluate the relationship between first-trimester crown-rump length (CRL) and birthweight (BW) Z scores. Retrospective cohort study. Two tertiary centres in France. Three hundred and seventeen pregnancies conceived through assisted reproductive techniques between April 2001 and December 2008. We used CRL and worked forward to BW. Only pregnancies examined during the first trimester by an Fetal Medicine Foundation-certified operator were included. CRL was expressed as Z scores, and BW was transformed into Z scores by taking gestational age and gender into account. The influence of abnormal first-trimester CRL Z scores on BW was examined. Weight and gestational age at birth. Birth weight was significantly greater in babies with larger CRL: BW Z scores (± SD) were -0.36 (± 1.05), -0.27 (± 0.97), -0.10 (± 1.04) and 0.13 (± 0.96) in the first, second, third and fourth quartiles of CRL Z scores, respectively (P = 0.01). In contrast, there was no difference in gestational length according to the quartiles of the CRL Z scores. The CRL Z score was a significant predictor of the BW Z score (β = 0.17, P = 0.001). After adjustment for maternal body mass index, a one-point increase in the first-trimester CRL Z score (i.e. 3.6 mm) was associated with a 39% decrease, 64% increase, 114% increase and 62% increase in the risk of having a BW below the 10th centile [odds ratio (OR), 0.61; 95% confidence intervals (95% CI), 0.39; 0.95; P=0.03], above the 90th centile (OR, 1.64; 95% CI, 1.03; 2.60; P = 0.02), above the 95th centile (OR, 2.14; 95% CI, 1.25; 3.68; P = 0.006) and above 4000 g (OR, 1.62; 95% CI, 1.04; 2.51; P = 0.04), respectively. Variations in BW may be partly explained by differences in growth trajectories that may express as early as the first trimester.

Supplemental l-Arginine Shortens Gestation Length and Increases Mare Uterine Blood Flow before and after Parturition

Supplementing diets with l-Arginine (Arg) improves female reproductive performance and reproductive blood flow in other species. The objectives of this study were to investigate uterine artery blood flow changes before and after parturition, and evaluate blood flow in Arg supplemented and control mares by Doppler ultrasonography. Sixteen light-horse mares began Doppler ultrasonography evaluation, 21 days before expected foaling date (EFD) and continued until day 7 postparturition. The mares under treatment (n = 8) were supplemented with 100 g Arg, once daily, beginning with 21 days before EFD. Blood flow measurements were calculated as pulsatility index (PI) and resistance index (RI) for both uterine arteries, either ipsilateral or contralateral; to uterine horn of established pregnancy; defined gravid uterine artery (GUA) and non-gravid uterine artery (NGUA), respectively. The mares under treatment had a shorter gestation length (337 ± 1.7 days) as compared to control (345 ± 2.1 days; P ≤ .05). No differences in gestation length were observed between groups when examined by age, parity, EFD, or sex of foal. Both GUA and NGUA uterine artery diameter decreased from the day before parturition to day 7 after parturition ( P ≤ .001). During this time period, both PI and RI increased ( P ≤ .01); indicating less blood flow. A treatment effect was observed with Arginine-treated mares having greater blood flow prepartum in the NGUA ( P ≤ .001) and postpartum in the GUA ( P ≤ .05), for both indices. The data demonstrated that supplementing mares with Arg shortened gestation length and increased uterine arterial blood flow before and after parturition.

Gestational Outcome in Rats That Consumed Aqueous Extract of Hibiscus sabdariffa During Pregnancy

The present study was designed to investigate the effect of consumption of aqueous extract of Hibiscus sabdariffa (HS) during pregnancy on fluid and food intake, weight gain during pregnancy, length of gestation, litter size and birth weight. Eighteen in-bred virgin female Sprague-Dawley rats aged between 1012 weeks and weighing 125 ± 5.5g (mean ± SEM) with two consecutive regular 4-day estrus cycle were used for this study. These rats were randomly assigned to one of three groups on gestational day one. Group A (control) were given tap water to drink throughout pregnancy, while groups B and C were given 0.6gextract/100ml and 1.8g-extract/100ml respectively to drink throughout pregnancy. All groups had normal rat chow and their respective drinking solution ad libitum. Mean fluid and food intake and total pregnancy weight gain were significantly reduced in the HS group. There was no significant difference in length of gestation among the various groups but there was a significant reduction in litter size and a significant increase in litter birth weight in HS groups (B and C) compared with control group (A). There were no apparent malformations at birth.

Cytokine Gene Polymorphisms and Length of Gestation

To estimate whether there is an association between length of gestation and gene polymorphisms that effect transcription of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), or interleukin-1β (IL-1β). Blood for DNA analysis was collected from 834 women at high risk enrolled in a randomized, clinical trial of omega-3 fatty acid supplementation for the prevention of recurrent preterm birth. Genotyping was performed for three single nucleotide polymorphisms (SNPs), TNF-α -308, IL-6 -174, and IL-1β +3954. Women with the homozygous minor genotype were compared with women with either the heterozygous or the homozygous major genotype. Kaplan-Meier curves of gestational age at delivery and odds ratios for extreme preterm delivery were adjusted for African-American race and treatment group. Women who were homozygous for the minor allele at the -308 position in the promoter region of the TNF-α gene had significantly shorter length of gestation than women who were either heterozygous or homozygous for the major allele (adjusted hazard ratio 1.74, 95% confidence interval [CI] 1.04-2.90, P=.03). Among women with this genotype, 20% (3/15) experienced extreme spontaneous preterm delivery (less than 28 weeks of gestation; adjusted odds ratio 7.51, 95% CI 1.84-30.72, P=.005). There was no difference in length of gestation or risk of extreme spontaneous preterm delivery by genotype for the IL-6 -174 or the IL-1β +3954 SNP. Polymorphism at the -308 position in the TNF-α promoter region is associated with shorter gestation and an increased risk of spontaneous extreme preterm delivery. ClinicalTrials.gov, www.clinicaltrials.gov, NCT00135902. II.

Impact of antenatal selective serotonin reuptake inhibitor exposure on pregnancy outcomes in mice

This study investigates fluoxetine (FLX) exposure as an etiology for altered gestational length and adverse pregnancy outcomes. Two experiments were performed exposing mice to drinking water (H(2)O) or H(2)O+FLX. Primary outcomes included gestational length, litter size, and live birth rate. In experiment 1, time-mated dams were monitored for spontaneous birth, and gestational length was calculated. In experiment 2, dams were dissected on day 14 to verify litter size and qualities of embryo implantation. There was no difference in gestational length between H(2)O dams (480.7 ± 13.2 hours) and H(2)O+FLX dams (483.5 ± 10.1 hours), P = .70. Mean litter size was decreased in H(2)O+FLX dams (4.1 ± 1.3/litter) compared to H(2)O dams (5.5 ± 1.9/litter), P = .04. H(2)O+FLX dams were less likely to have live births (25.4%) compared to H(2)O dams (49.3%), P = .01. Antenatal FLX exposure did not statistically alter gestational length, but did affect litter size and spontaneous loss in mice. This warrants further investigation.

Developmental and neurobehavioral effects of perinatal exposure to diets with different ω-6:ω-3 ratios in mice

ObjectiveTo investigate in mice the effect of diets enriched with soy or sunflower oil with different ω-6:ω-3 ratios on gestation, reproductive success, physical maturation, and the neurobiological development of the pups. MethodsDams were assigned, throughout gestation and lactation, to different groups: a commercial diet (CD), a soy oil–enriched diet (SOD), or a sunflower oil–enriched diet (SFOD). Measurements during gestation were dams' body weights and daily food intakes. Measurements in the offspring were physical parameters (body weight, body length, body mass index, fur appearance, pinna detachment, incisor eruption, eye opening, and puberty onset) and behavioral preweaning tests (surface righting reflex, negative geotaxis, and cliff avoidance). ResultsThe SOD and SFOD dams became significantly heavier than the CD dams from gestational days 14 and 19, respectively, to parturition. There were no significant differences in gestational length or food consumption during pregnancy or lactation or in maternal weight during lactation. Diets did not modify litter size, sex ratio, survival index at weaning, or body weight. The SFOD and SOD offspring were significantly shorter than the CD offspring at weaning. The mean offspring physical scores of SOD and SFOD offspring were higher than CD offspring and simple reflexes were earlier in the SOD and SFOD groups. In SFOD offspring, puberty onset was significantly delayed, at postnatal days 26 and 27 in male and female offspring, respectively. ConclusionThis study suggests that the maintenance of an adequate ω-6:ω-3 ratio is necessary for the optimal growth and development of murine offspring. In populations that do not have sufficient provision of polyunsaturated fatty acids in the diet, their consumption would be advisable during gestation and lactation because these improve most neurodevelopmental outcomes included in this study.

Trends and seasonality in birth frequency: a comparison of Muslim and Jewish populations in southern Israel: daily time series analysis of 200 009 births, 1988-2005

The aim of this study was to assess effects of natural and artificial seasonality on reproduction in a large cohort of Muslim and Jewish women, living in the same geographic area. Population included all births between January 1988 and December 2005 (6613 daily records of 200 009 births) at the Soroka University Medical Center (southern Israel). A 'classical' time series technique based on generalized linear regression models was used. A systematic increase in the number of births during Ramadan was observed in the Muslim (P < 0.001), but not in the Jewish, population. This 'Ramadan effect', adjusted for trend and seasonal factors, was statistically significant only in Muslim multiparae (P < 0.001), where the model explained more than 48% of the variance, compared with 7% in Jewish multiparae. Seasonal birth variations in Muslim primiparae were not associated with Ramadan and were similar to those in Jewish primiparae. There were no differences in length of gestation associated with Ramadan. The findings suggest an increased conception rate following the Hajj pilgrimage, which support the hypothesis that seasonality of reproductive behavior is influenced by socio-cultural factors more than by geographic and climatic factors, and can help plan preconception interventions in Muslim populations in southern Israel.

Maternity Leave In The Ninth Month of Pregnancy and Birth Outcomes Among Working Women

The health effects of antenatal maternity leave have been scarcely evaluated. In California, women are eligible for paid benefits up to 4 weeks before delivery. We explored whether leave at > or =36 weeks gestation increases gestation and birthweight, and reduces primary cesarean deliveries among full-time working women. Drawing from a 2002--2003 nested case-control study of preterm birth and low birthweight among working women in Southern California, we compared a cohort of women who took leave (n = 62) or worked until delivery (n = 385). Models weighted for probability of sampling were used to calculate hazards ratios for gestational age, odds ratios (OR) for primary cesarean delivery, and multilinear regression coefficients for birthweight. Leave-takers were similar to non-leave-takers on demographic and health characteristics, except that more clerical workers took leave (p = .02). Compared with non-leave-takers, leave-takers had almost 4 times lower odds of cesarean delivery after adjusting for covariates (OR, 0.27; 95% confidence interval [CI], 0.08-0.94). Overall, there were no marked differences in length of gestation or mean birthweight. However, in a subgroup of women whose efforts outstripped their occupational rewards, gestation was prolonged (hazard ratio for delivery each day between 36 and 41 weeks, 0.56; 95% CI, 0.34-0.93). Maternity leave in late pregnancy shows promise for reducing cesarean deliveries and prolonging gestation in occupationally strained women.

Maternal Immune Challenge During Early Embryo Development Affects Blastocyst Cell Lineage Ratio and Postnatal Phenotype.

Maternal infection during gestation is an established cause of abortion, premature birth and intrauterine growth restriction. In addition, there is a strong association between activation of the maternal immune response during mid-gestation and neurological abnormalities in the offspring. At present little is known about the consequences of maternal immune activation during early gestation. The preimplantation embryo has been identified as a critical developmental stage during which environment can program changes to postnatal phenotype. Here, we investigated the sensitivity of preimplantation mouse embryos to maternal immune challenge in the short- and long-term. Virgin female MF-1 mice were mated and randomly assigned to one of four treatment groups; control (saline only), 10, 50 or 150µg/kg of bodyweight lipopolysaccharide (LPS; Salmonella enterica enteritidis ). On gestational day 0.5 (GD0.5), successfully mated females were injected intraperitoneally with saline or LPS dose. Mice were either culled at GD3.5 to assess short-term consequences in blastocysts or allowed to go to term to investigate potential long-term changes in offspring body mass, behaviour and systolic blood pressure (SBP). All postnatal data were analysed using a multilevel random effects regression model (SPSS) which takes into account the hierarchical nature of the dataset. Blastocysts were differentially labelled to assess inner cell mass (ICM) and trophectoderm (TE) cell numbers. Blastocysts from 10µg/kg LPS mothers had more TE cells than those from control mothers (p<0.05). Blastocysts from 50 and 150µg/kg LPS mothers had fewer ICM cells than blastocysts from control mothers (p<0.05). These effects lead to a reduced ICM:TE cell ratio at each LPS dose compared with control (p<0.05). At birth, pups were weighed and litter size adjusted to 3 males and 3 females where possible. Offspring were weighed weekly thereafter and underwent a series of behavioural tests and SBP measurements (tail cuff) until 30 weeks of age. No difference in gestation length or male:female offspring ratio was observed between treatment groups. Interestingly, 10µg/kg LPS mothers had larger litters than control mothers (p<0.01). Body weight was not different between treatment groups at any time point. In the open field behavioural test, both male and female offspring from LPS treated mothers displayed reduced levels of exploratory behaviour compared with controls. For example, male offspring from 150µg/kg LPS mothers displayed fewer rears and jumps than control males at 20 weeks (p<0.05). Furthermore, males from 10µg/kg LPS mothers had elevated SBP at 28 weeks (p<0.05), but females showed no difference in SBP at any time point. These data indicate the sensitivity of the preimplantation mouse embryo to maternal immune activation in vivo leading to altered blastocyst cell allocation, increased litter size (in the lowest dose LPS treatment group) and altered developmental potential; including abnormal behaviour and elevated blood pressure in adult life (also in the lowest dose LPS treatment group). This work serves to highlight maternal immune activation during preimplantation developmentas an important route by which adverse changes in postnatal phenotype can potentially arise; and emphasises the importance of further study into this emerging area of research. This research is funded by a BBSRC studentship (to CLW) and by NIH and MRC grants (to TPF).

Low protein diet fed exclusively during mouse oocyte maturation leads to behavioural and cardiovascular abnormalities in offspring

Early embryonic development is known to be susceptible to maternal undernutrition, leading to a disease-related postnatal phenotype. To determine whether this sensitivity extended into oocyte development, we examined the effect of maternal normal protein diet (18% casein; NPD) or isocaloric low protein diet (9% casein; LPD) restricted to one ovulatory cycle (3.5 days) prior to natural mating in female MF-1 mice. After mating, all females received NPD for the remainder of gestation and all offspring were litter size adjusted and fed standard chow. No difference in gestation length, litter size, sex ratio or postnatal growth was observed between treatments. Maternal LPD did, however, induce abnormal anxiety-related behaviour in open field activities in male and female offspring (P < 0.05). Maternal LPD offspring also exhibited elevated systolic blood pressure (SBP) in males at 9 and 15 weeks and in both sexes at 21 weeks (P < 0.05). Male LPD offspring hypertension was accompanied by attenuated arterial responsiveness in vitro to vasodilators acetylcholine and isoprenaline (P < 0.05). LPD female offspring adult kidneys were also smaller, but had increased nephron numbers (P < 0.05). Moreover, the relationship between SBP and kidney or heart size or nephron number was altered by diet treatment (P < 0.05). These data demonstrate the sensitivity of mouse maturing oocytes in vivo to maternal protein undernutrition and identify both behavioural and cardiovascular postnatal outcomes, indicative of adult disease. These outcomes probably derive from a direct effect of protein restriction, although indirect stress mechanisms may also be contributory. Similar and distinct postnatal outcomes were observed here compared with maternal LPD treatment during post-fertilization preimplantation development which may reflect the relative contribution of the paternal genome.

Morphological features of the placenta at term in the Martina Franca donkey

This study was designed to establish the morphological features of the placenta of the Martina Franca jenny. Ten placentas were harvested at the time of foal delivery and examined both for gross and histological characteristics. The following factors were determined: the total weight and volume of the placenta and its components, the surface area of the allantochorion, umbilical cord length and site of insertion, and the diameter of the umbilical cord vessels and vascular pattern type. The weight of the placenta was similar to previously reported for ponies, and represented 12% of foal birth weight. Umbilical cord length was similar to that in the horse but longer than in the pony, while cord weight was intermediate between the two. In a histological examination, numerous strong villi were observed at sites corresponding to the non-pregnant and pregnant horn and uterine body. No villi were detected in the area overlying the cervical star. Despite obvious similarities between the donkey and horse placenta, specific morphological features do exist, and are possibly related to the differences in length of gestation.

Fish Oil in Various Doses or Flax Oil in Pregnancy and Timing of Spontaneous Delivery: A Randomized Controlled Trial

Previous studies have suggested that a diet containing long-chain n-3 fatty acids derived from fish oil may delay spontaneous delivery. The investigators, in a randomized, controlled trial, addressed this hypothesis and also sought to determine whether alpha-linolenic acid (ALA), in the form of flax oil capsules, might have the same effect. Participants were 3098 women who reported a low intake of fish and who were randomized to receive one of 5 doses (0.1, 0.3, 0.7, 1.4, or 2.8 g) of eicosapentaenoic acid and docosahexaenoic acid daily, 2.2 g daily of ALA, or no treatment. Supplementation began at 17 to 27 weeks gestation and continued until delivery. The treatment groups were similar with respect to age, parity, gestational age, fish consumption, body mass index, and smoking. Analyzing singleton live-born pregnancies, no significant difference in gestational length was found between control women and any of the treatment groups whether comparing mean gestational ages or hazard rates of spontaneous delivery. This held for both intention-to-treat analyses and analyses based on the participants only. There were no apparent differences in intake of any of the fatty acids between the treatment groups. The difference in time to spontaneous delivery between pregnant women given the highest dose of fish oil and control women was less than 1 day. A majority of women in the treatment groups failed to continue taking their capsules up to the time of delivery. These findings may indicate that there is in fact no meaningful effect of dietary n-3 fatty acids on the timing of spontaneous delivery. It also is possible that there is a rapidly diminishing effect that depends on continued supplementation.

High mineral and vitamin E intake by pregnant ewes lowers colostral immunoglobulin G absorption by the lamb1

A 2 x 2 factorial arrangement of treatments with 78 mature ewes was used to evaluate the effects of supplementing the pregnant ewe's diet with high levels of minerals and vitamin E on immunoglobulin G (IgG) absorption by the lamb and whether any altered efficacy of IgG absorption was due to the colostrum or to the lamb. The ewes were estrus-synchronized in October and housed in wk 10 of gestation. In the final 7 wk of gestation, a grass silage-based diet, offered ad libitum, was supplemented with 500 g of a 19% CP concentrate, and from 1 wk later until lambing, half the ewes was offered 48 g of a mineral/vitamin supplement containing 6.5 g of Ca, 4.9 g of P, 5.9 g of Mg, 4.0 g of Na, 790 mg of Zn, 3.5 mg of Se, 40 mg of I, 200 mg of Mn, 20 mg of Co, and 40 IU of vitamin E. At birth, the lambs were allocated to one of four treatments in a 2 x 2 factorial arrangement, with lamb origin and colostrum origin as the two factors. The lambs born to ewes not offered the mineral supplement were fed colostrum obtained from their own dams or from ewes in the mineral-supplemented treatment, whereas lambs born to ewes given supplemental minerals were fed colostrum obtained either from their dams or from ewes in the control treatment. The ewes were milked at 1, 10, and 18 h postpartum and the lambs were fed using a stomach tube. A 5-mL blood sample was taken from each lamb at 24 h postpartum for IgG analysis. The level of fecal adhesion to the upper tail/rump area of the lamb was subjectively scored at 72 h postpartum. There was no difference in gestation length, lamb birth weight, colostrum yield, or IgG production (P = 0.16 to 0.82). When ewes were fed supplemental minerals, the serum IgG content of the progeny was lower than in their control counterparts (6.8 vs. 16.1 g/L; P < 0.001), regardless of whether the lamb received colostrum from ewes with or without access to supplementary minerals. The difference in serum IgG concentrations at 24 h postpartum was a direct reflection of a compromised efficiency in IgG absorption. The progeny of ewes with access to minerals had higher (P < 0.05) levels of fecal adhesion, which was not related to the origin of the colostrum, indicating altered digestive function in these lambs. We conclude, using the sheep as a model, that high mineral intakes in late pregnancy not only lower serum IgG concentrations in the lamb, but also that high mineral intakes result in the neonate being preprogrammed at birth so that it is born with a compromised ability to absorb colostral IgG.

Differential effects of fish oil and folic acid supplementation during pregnancy in rats on cognitive performance and serum glucose in their offspring

Objective We studied the effect of folic acid and polyunsaturated fatty acid supplementation during pregnancy in Wistar albino rats on cognitive performance and serum glucose concentrations in their pups. Methods Pregnant female rats from four groups ( n = 6/group) were fed casein diets with 18% protein and 2 mg of folic acid/kg of diet (group I), 12% protein and no folic acid (group II), 12% protein and 8 mg of folic acid/kg of diet (group III), or 12% protein and 70 g of cod liver oil/kg of diet (group IV). All pups were weaned on standard control diet with 18% protein. Cognitive performance, brain fatty acid profile, and serum glucose concentrations were studied in offspring at age 6 mo. Results There was no significant difference in length of gestation or litter size, but the litter weight for group IV was lower ( P = 0.047) than that for group I. After weaning, males in group II had lower ( P < 0.05) body weights, but those in group III had weights comparable to those in group I for both sexes. In group IV, body weights were lower beyond 15 wk ( P < 0.05). Relative brain weight and cognitive performance were significantly higher ( P < 0.05) in group IV males and showed higher levels of brain γ-linolenic acid. Further, these animals had serum glucose levels comparable to those of control animals at age 6 mo, whereas serum glucose levels were higher in males from groups II ( P = 0.01) and III ( P = 0.01). Conclusion Fish oil supplementation during pregnancy improved cognitive performance and maintained glucose levels into adulthood, unlike folic acid supplementation, which supported only fetal growth and did not maintain glucose levels.

Predicting calving curves for herds using controlled breeding programs

A database of gestation lengths (GLs) was generated over 2 years in three large dairy herds which had used controlled breeding programs (CBPs). This was compared with a database comprising a single calving season of 124 seasonally calving dairy herds using conventional artificial insemination programs (CAIs). Multiphase regression was used to derive two corrected databases by excluding outlying values of gestation length. The mean gestation length derived from the CBP database was slightly shorter than that of the CAI database (280.80 days, n = 775 versus 281.87 days, n = 1986; P < 0.001), but the two databases had similar variances (SD = 4.21 and 4.12 days, for CBP and CAI respectively; P = 0.36). The results from the multilevel analysis showed a mean difference in gestation length of 0.94 (SE 0.50) days; (P = 0.06) between CAI and CBP. The mean gestation length and its SD from the CBP data were used to predict calving curves in herds using CBPs which could be compared with observed calving data. The observed and predicted calving patterns generated for two farms were not significantly different (P = 0.37 and 0.31). The accuracy of the predictions was critically dependent on the completeness and accuracy of conception data and details for cows induced to calve prematurely.

Vitrification of in vitro produced bovine embryos: in vitro and in vivo evaluations

The efficacy of different vitrification solutions to cryopreserve in vitro produced bovine blastocysts was evaluated based upon in vitro development of embryos in culture and on in vivo development of embryos transferred into recipients. In the first experiment, ethylene glycol+glycerol (Eg+Gly) + different sucrose concentrations were evaluated. There were no significant differences in development rates among solutions. As for hatching, the Eg+Gly+ 0.1 M sucrose group had a greater rate as compared with Eg+Gly+0 M sucrose and Eg+Gly+0.5 M sucrose groups in the evaluations of Day 6, Day 7 and Day 6+Day 7 embryos; and, Eg+Gly+0.3 M sucrose group had a greater rate as compared with the Eg+Gly+0 M sucrose and Eg+Gly+0.5 M sucrose groups in evaluations of Day 6 and Day 6+Day 7 embryos. There were no significant differences in development and hatching rates between Day 6 and 7 in in vitro produced bovine embryos within each treatment group. There were significant differences in nuclei number after vitrification between Eg+Gly+0.1 M and Eg+Gly+0 M sucrose groups and the Eg+Gly+0.5 M sucrose group. Pregnancy after 60 days of transfer and calving rates showed a difference between in vivo produced embryos freshly transferred and in vitro produced embryos vitrified with Eg+Gly+0.3 M. There were no significant differences in gestation length and sex ratio between treatments. As for birth weight, there were significant differences between fresh in vivo produced embryos and all treatments of in vitro produced embryos. There were significant differences in dystocial parturition between in vivo produced embryos and all treatments with in vitro produced embryos. These results demonstrate that vitrification can be used successfully in the cryopreservation of in vitro produced bovine embryos, and that it might be considered for use in commercial programs.

Alpha-foetoprotein in umbilical cord in relation to severe pre-eclampsia, birth weight and future breast cancer risk.

Women born after pre-eclamptic pregnancies have been reported to be at reduced risk of breast cancer as adults, because of reduced intrauterine oestrogen influence on breast tissue; high levels of α-foetoprotein (a glycoprotein with anti-oestrogenic properties), however, could also be important. In severe pre-eclampsia, placental function and foetal growth are reduced, and umbilical cord plasma levels of α-foetoprotein could reflect the underlying processes. Umbilical cord blood was collected in 12 804 consecutive deliveries. Among 307 pregnancies with clinical pre-eclampsia, 66 singleton pregnancies were identified as clinically severe, and 610 singleton pregnancies were selected as controls. Oestradiol and α-foetoprotein were measured from umbilical plasma, and birth weight was standardized as the ratio between the observed and expected birth weight, adjusted for differences in gestation length and offspring sex. Cord plasma levels of α-foetoprotein were significantly higher in severe pre-eclampsia than controls (P<0.01) after adjustment for gestational age and birth weight. For oestradiol, there was no difference in cord plasma levels between the severe pre-eclampsia group and controls, after adjustment for length of gestation and birth weight. These results suggest that an anti-oestrogenic effect associated with pre-eclampsia may be mediated through high levels of α-foetoprotein rather than low levels of oestradiol.British Journal of Cancer (2002) 86, 728–731. DOI: 10.1038/sj/bjc/6600125 www.bjcancer.com© 2002 Cancer Research UK