Variation In Birth Weight Research Articles

Associations of Maternal Cell-Phone Use During Pregnancy With Pregnancy Duration and Fetal Growth in 4 Birth Cohorts.

Results from studies evaluating potential effects of prenatal exposure to radio-frequency electromagnetic fields from cell phones on birth outcomes have been inconsistent. Using data on 55,507 pregnant women and their children from Denmark (1996–2002), the Netherlands (2003–2004), Spain (2003–2008), and South Korea (2006–2011), we explored whether maternal cell-phone use was associated with pregnancy duration and fetal growth. On the basis of self-reported number of cell-phone calls per day, exposure was grouped as none, low (referent), intermediate, or high. We examined pregnancy duration (gestational age at birth, preterm/postterm birth), fetal growth (birth weight ratio, small/large size for gestational age), and birth weight variables (birth weight, low/high birth weight) and meta-analyzed cohort-specific estimates. The intermediate exposure group had a higher risk of giving birth at a lower gestational age (hazard ratio = 1.04, 95% confidence interval: 1.01, 1.07), and exposure-response relationships were found for shorter pregnancy duration (P < 0.001) and preterm birth (P = 0.003). We observed no association with fetal growth or birth weight. Maternal cell-phone use during pregnancy may be associated with shorter pregnancy duration and increased risk of preterm birth, but these results should be interpreted with caution, since they may reflect stress during pregnancy or other residual confounding rather than a direct effect of cell-phone exposure.

Relationships of body surface thermography with core temperature, birth weight and climatic variables in neonatal lambs born during early spring in an arid region.

The main cause of death in newborn lambs is hypothermia, so is necessary to identify the factors affecting variations in body surface temperatures of sheep neonates because approximately 60% of their body heat losses occur through the skin. This study aimed to establish relationships among body surface thermography from different regions with rectal temperature (RT), birth weight (BW) and climatic variables in hair breed newborn lambs during early spring in an arid region. Data of body surface temperatures measured by infrared thermography (entire head, eye, muzzle, ear, entire body, shoulder, rump, loin, right flank, belly and leg), RT and BW were collected at 0, 12 and 24 h post-lambing in 85 lambs born in early spring. Relative humidity [RH], temperature [Te] and temperature-humidity index [THI] were also recorded. RT was not correlated with surface temperatures at 0 and 24 h, but it was at 12 h with all of them (0.36 ≤ r ≤ 0.44). BW and some surface temperatures were negatively correlated at 0 and 24 h (-0.24 ≤ r ≤ -0.30), but positively at 12 h (0.25 ≤ r ≤ 0.27). All surface temperatures were positively correlated (0.51 ≤ r ≤ 0.85) with Te and THI in the three sampling times. Principal component (PC) analysis showed that PC1 explained the majority of the variance (71-72%), followed by PC2 (8-9%) at 0, 12 and 24 h. Body surface temperatures increased as Te and THI also increased, but decreased with the increase in HR. In conclusion, under early spring environment (predominantly cold), the variations in body surface temperatures of hair sheep neonates were more closely related to climatic variables than to RT and BW. Thermography proved to be an effective tool to determine body heat loss by radiation in skin of neonate lambs.

Birthweight predictive factors of the children of adolescent mothers

The objective of the present study was to identify the predictive factors of birthweight in newborns of adolescent pregnant women. This is a cross-sectional, cross-sectional study with a sample composed of 751 adolescent postpartum women, aged 10 years or more and 20 years or less, developed in a public maternity hospital in Rio de Janeiro. The variables evaluated were anthropometric, sociodemographic, obstetric, maternal and prenatal care, and conditions at conception. Different linear regression models were tested by the stepwise method to identify predictors of birthweight. The mean maternal age was 17 years (±1.60). The predictive variables of birth weight, identified in the bivariate analysis were: maternal age; number of family members; family income per capita, number of births; number of prenatal consultations and consultations with the nutritionist in prenatal care; pre-gestational BMI; total weight gain; weight gain in the second and third trimesters, and gestational age at delivery. Among the predictive variables of birthweight were gestational age at delivery (β= 92.54, p= 0.001), number of consultations with the nutritionist in the prenatal period (β= 53.84, p= 0.001), weight gain in the second (β= 32.07, p= 0.003) and in the third (β= 26.70, p= 0.007) trimesters of gestation, pre-gestational BMI (β= 19.10, p= 0.017), and, negatively, the number of people in the family (β= -32.90, p= 0.033). Efforts should be made to ensure that childbirth is at term, follow-ups with the nutritionist should be regular, aiming at monitoring gestational weight gain, and greater attention should be paid to pregnant women with adverse sociodemographic conditions, implementing strategies to improve the birth weight of newborns of adolescent pregnant women.

Individual variation in longitudinal postnatal development of the primate brain.

Quantifying individual variation in postnatal brain development can provide insight into cognitive diversity within a population and the aetiology of common neuropsychiatric and neurodevelopmental disorders. Non-invasive studies of the non-human primate can aid understanding of human brain development, facilitating longitudinal analysis during early postnatal development when comparative human populations are difficult to sample. In this study, we perform analysis of a longitudinal MRI dataset of 32 macaques, each with up to five magnetic resonance imaging (MRI) scans acquired between 3 and 36months of age. Using nonlinear mixed effects model we derive growth trajectories for whole brain, cortical and subcortical grey matter, cerebral white matter and cerebellar volume. We then test the association between individual variation in postnatal tissue volumes and birth weight. We report nonlinear growth models for all tissue compartments, as well as significant variation in total intracranial volume between individuals. We also demonstrate that regional subcortical grey matter varies both in total volume and rate of change between individuals and is associated with differences in birth weight. This supports evidence that birth weight may act as a marker of subsequent brain development and highlights the importance of longitudinal MRI analysis in developmental studies.

Follicular development of sows at weaning in relation to estimated breeding value for within-litter variation in piglet birth weight

In this study we aimed to identify possible causes of within-litter variation in piglet birth weight (birth weight variation) by studying follicular development of sows at weaning in relation to their estimated breeding value (EBV) for birth weight variation. In total, 29 multiparous sows (parity 3 to 5) were selected on their EBV for birth weight variation (SD in grams; High-EBV: 15.8±1.6, N=14 and Low-EBV: −24.7±1.5, N=15). The two groups of sows had similar litter sizes (15.7 v. 16.9). Within 24 h after parturition, piglets were cross-fostered to ensure 13 suckling piglets per sow. Sows weaned 12.8±1.0 and 12.7±1.0 piglets, respectively, at days 26.1±0.2 of lactation. Blood and ovaries were collected within 2 h after weaning. The right ovary was immediately frozen to assess average follicle size and percentage healthy follicles of the 15 largest follicles. The left ovary was used to assess the percentage morphologically healthy cumulus-oocyte complexes (COCs) of the 15 largest follicles. To assess the metabolic state of the sows, body condition and the circulating metabolic markers insulin, IGF1, non-esterified fatty acid, creatinine, leptin, urea and fibroblast growth factor 21 were analysed at weaning. No significant differences were found in any of the measured follicular or metabolic parameters between High-EBV and Low-EBV. A higher weight loss during lactation was related to a lower percentage healthy COCs (β= −0.65, P=0.02). Serum creatinine, a marker for protein breakdown, was negatively related to average follicle size (β= −0.60, P=0.05). Backfat loss during lactation was related to a higher backfat thickness at parturition and to a higher average follicle size (β=0.36, P<0.001) at weaning. In conclusion, we hypothesise that modern hybrid sows with more backfat at the start of lactation are able to mobilise more energy from backfat during lactation and could thereby spare protein reserves to support follicular development.

Influence of aerobic exercise on maternal lipid levels and offspring morphometrics

Maternal BMI, lipid levels (cholesterol, triglyceride, LDL, HDL), and exercise amount are interrelated and each influence offspring body size. This study proposed to determine the influence of exercise on maternal lipid levels and infant body size. We had 36 participants complete these measures. Participants in the aerobic exercise intervention (n = 14) completed three 50-min sessions weekly from 16 weeks gestation to delivery and were compared with a non-exercise control group (n = 22). Maternal lipid profiles were assessed at 16 and at 36 weeks gestation. Fetal body size was measured at 36 weeks gestational age using ultrasound assessment. Neonatal body size measures were acquired from birth records. Statistical analysis included two-sample t-tests, correlations, and regression models. Participants were similar in age, pre-pregnancy BMI, gravida, parity, education, and gestational weight gain (GWG). There were no differences in gestational age, Apgar scores at 1 and 5 min for infants of exercisers relative to controls. Exercisers had higher pre-training triglycerides (p = 0.004) and pregnancy change in triglycerides (p = 0.049) compared to controls. Head circumference was significantly larger in exercise exposed infants relative to infants of controls. Pregnancy METs had a positive relationship with birth length (r = .445, p = .006) and birth weight (r = .391, p = .02). GWG had a moderate, positive relationship with fetal abdominal circumference (r = .570, p = .004). Regression analysis indicated 5 predictors explained 61.7% of the variance in birth weight (Adj.R2 = 0.469, F(5,13) = 5,13, p = 0.02); it was found that pregnancy METs (β = .724, p = .007), 36 week cholesterol (β = 1.066, p = .02), and 36 week LDL (β = -1.267, p = .006) significantly predict birth weight. Regression analysis indicated 4 predictors explained 43.8% of the variance in birth length (Adj.R2 = 0.306, F(4,17) = 3.32, p = 0.04); it was found that pregnancy METs (β = .530, p = .03), and 36 week LDL (β = -.891, p = .049) significantly predict birth length. The primary association and predictors of infant body size was related to pregnancy exercise and late pregnancy cholesterol and LDL levels. Considering these relationships, it is essential that women maintain aerobic exercise during pregnancy, but should also be cognizant of lipid levels during their pregnancy. Therefore intervention during pregnancy focused on infant body size should involve exercise and and quality nutritional intake foods during pregnancy.

Associations between Infant Birth Weight and Seasonal Variations in PM2.5 Exposure during Pregnancy: A Prospective Cohort Study in a Rural Community in China

Associations between Infant Birth Weight and Seasonal Variations in PM2.5 Exposure during Pregnancy: A Prospective Cohort Study in a Rural Community in China

Associations between Infant Birth Weight and Seasonal Variations in PM2.5 Exposure during Pregnancy: A Prospective Cohort Study in a Rural Community in China

Background: Exposure to PM2.5 (fine particulate matter) pollutants in pregnancy has generally been found to be associated with infant low birthweight. In rural China, exposure of pregnant women to ...

Genetic analyses in small-for-gestational-age newborns

SGA is often defined as a birth weight and/or length < −2 SDS for gestational age and gender [43]. A frequent cause of SGA is fetal growth restriction (FGR), often associated with perinatal mortality and morbidity and also implicated in a higher risk of cardio-metabolic disease in adulthood. Currently, no tools are available to predict or prevent FGR. Both genetic and environmental factors may affect fetal growth, but the underlying molecular mechanisms are still unclear. Genetic and epigenetic factors account for 30-50% of the variation in birth weight [44]. Chromosomal anomalies account for up to 19% of FGR fetuses, while the rate of submicroscopic duplications/deletions and single-gene disorders in FGR with normal karyotype is not defined [44]. A recent study showed that genomic microarray analysis (CMA) identifies sub-microscopic anomalies in 6.8% of fetuses with early growth restriction after common aneuploidies were excluded [45]. To date, the use of CMA is recommended for a fetus with one or more major malformations identified by ultrasound. Epigenetic mechanisms also explain abnormal fetal growth in conditions such as Silver-Russell and Beckwith-Wiedemann syndrome.

Cryopreserved Embryo Replacement is Associated with Higher Birthweight Compared with Fresh Embryo: Sibling Cohort Study

Background: It is known that birth weight (BW) is higher after frozen embryo transfer (FET) than after fresh embryo replacement. No study has compared the BW of siblings conceived using the same oocyte/embryo cohort but different transfer procedures (fresh vs frozen). The aim of this study was to determine whether the freezing-thawing procedure itself is involved in such difference. Methods: Multicenter retrospective study at the ART/PGD Department of Montpellier University Hospital, Clinique Ovo, Canada and Grenoble-Alpes University Hospital. The first cohort (Fresh/FET) included all in vitro fertilization (IVF) cycles where the older child was born after fresh embryo transfer (fresh, n=158) and the younger one after transfer of frozen supernumerary embryos conceived during the same IVF cycle (FET, n=158). The second cohort (FET/FET) included all IVF cycles where both older and younger child were born after FET of embryos from the same cohort (FET1, n=25; FET2, n=25). Findings: The mean adjusted BW of the FET group was significantly higher than that of the fresh group (3508.9 452.4 g vs 3237.7 463.3 g; p<0.01). The FET group showed increased risk to be large for gestational age (AOR 4.22; 95%CI 2.04-8.73). In the FET/FET cohort, the mean adjusted BW was higher for the younger baby by 93.1 g but this difference is not significant (3430.2 347.6 g vs 3337.1 391.9 g; p=0.3789). Interpretation: As both embryos were from the same IVF cycle, the only difference was the cryopreservation step, our results strongly suggest that cryopreservation is directly involved in the BW variation. Moreoever, comparing BW difference between Fresh/FET cohort and the FET/FET one, our study suggests that parity is not the only responsible in this difference, increasing the role of cryopreservation step in BW variation. Funding: Partially financial support was covered by INSERM U 1203. Declaration of Interest: None of the authors has any conflicts of interest to declare. Ethical Approval: Written informed consent was obtained for the use of data in national registries, and the local Institutional Review Boards approved the study. All patients at the Ovo clinic signed a treatment consent form that included consenting to the use of non-identifying information for publication purposes.

Smoking and Variation in the Hispanic Paradox: A Comparison of Low Birthweight Across 33 US States.

The Hispanic Paradox in birth outcomes is well documented for the US as a whole, but little work has considered geographic variation underlying the national pattern. This inquiry is important given the rapid growth of the Hispanic population and its geographic dispersion. Using birth records data from 2014 through 2016, we document state variation in birthweight differentials between US-born white women and the three Hispanic populations with the largest numbers of births: US-born Mexican women, foreign-born Mexican women, and foreign-born Central and South American women. Our analyses reveal substantial geographic variation in Hispanic immigrant-white low birthweight disparities. For example, Hispanic immigrants in Southeastern states and in some states from other regions have reduced risk of low birthweight relative to whites, consistent with a "Hispanic Paradox." A significant portion of Hispanic immigrants' birthweight advantage in these states is explained by lower rates of smoking relative to whites. However, Hispanic immigrants have higher rates of low birthweight in California and several other Western states. The different state patterns are largely driven by geographic variation in smoking among whites, rather than geographic differences in Hispanic immigrants' birthweights. In contrast, US-born Mexicans generally have similar or slightly higher odds of low birthweight than whites across the US. Overall, we show that the Hispanic Paradox in birthweight varies quite dramatically by state, driven by geographic variation in low birthweight among whites associated with white smoking disparities across states.

Birth-weight differences at term are explained by placental dysfunction and not by maternal ethnicity.

To investigate the influence of ethnicity, fetal gender and placental dysfunction on birth weight (BW) in term fetuses of South Asian and Caucasian origin. This was a retrospective study of 627 term pregnancies assessed at two public tertiary hospitals in Spain and Sri Lanka. All fetuses underwent biometry and Doppler examinations within 2 weeks of delivery. The influences of fetal gender and ethnicity, gestational age (GA) at delivery, cerebroplacental ratio (CPR) and maternal age, height, weight and parity on BW were evaluated by multivariable regression analysis. Fetuses born in Sri Lanka were smaller than those born in Spain (mean BW = 3026 ± 449 g vs 3295 ± 444 g; P < 0.001). Multivariable regression analysis demonstrated that GA at delivery, maternal weight, CPR, maternal height and fetal gender (estimates = 0.168, P <0.001; 0.006, P <0.001; 0.092, P = 0.003; 0.009, P = 0.002; 0.081, P = 0.01, respectively) were associated significantly with BW. Conversely, no significant association was noted for maternal ethnicity, age or parity (estimates = -0.010, P = 0.831; 0.005, P = 0.127; 0.035, P = 0.086, respectively). The findings were unchanged when the analysis was repeated using INTERGROWTH-21st fetal weight centiles instead of BW (log odds, -0.175, P = 0.170 and 0.321, P <0.001, respectively for ethnicity and CPR). Fetal BW variation at term is less dependent on ethnic origin and better explained by placental dysfunction. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Feed and reproductive efficiency differences between divergently selected lines for birthweight environmental variability in mice.

Sustainability has come to play an important role in agricultural production. A way to combine efficiency with sustainability might be by searching for robust animals that can be selected for the homogeneity of certain traits. Furthermore, the optimization of feed efficiency is one of the challenges to improve livestock genetics programmes, but this might compromise reproductive efficiency. Animals from two divergent mouse lines, regarding variability of birthweight, were used to check whether homogeneity was also related to both feed and reproductive efficiency. The objective of this study was to use these divergent lines of mice to compare them with their feed efficiency and the reproductive capacity. Animal weight, weight gain, feed intake, relative intake and cumulated transformation index were considered as feed efficiency traits. Animals from the low line had both lower weight and feed intake from 21 to 56days. They had a worse transforming index in the three last weeks when litter size was fitted as an effect of the model, but the lines become similar if the higher litter size of the low line was not included. Reproductively, the low line performed better considering the number of females having parturitions, the number of parturitions, and with higher litter size and survival in both parturitions. Hence, the low variability line was preferred because of reproductive efficiency without seriously affecting its feed efficiency. Homogeneity seemed to be related to robustness with similar feed efficiency but higher reproductive efficiency.

Regression Tree Approach for Assessing the Effects of Non-Genetic Factors on Birth Weight of Hemşin Lamb

This study examined effects of birth year, herd type, age of dam, lamb sex, birth type and lamb color on birth weight in Hemsin lambs using the regression tree method. The study used the data obtained from 9113 Hemsin lambs born between 2007-2010. The average birth weight of Hemsin lambs was found to be 3.55 kg and the standard deviation was 0.727 kg. Significant differences were found in birth weights of Hemsin lambs according to birth year (P&amp;lt;0.001), birth type (P&amp;lt;0.001) and lamb sec (P&amp;lt;0.01), whereas no statistically significant difference was found according to herd type, age of dam and lamb color (P&amp;gt;0.05). According to the regression tree diagram, the most important factors affecting birth weight of Hemsin lambs were birth year, birth type, sex, herd type and age of dam. The absence of lamb color in the regression tree diagram indicates its insignificant effect on birth weight. The low risk value (0.456) and high R-Squared value (0.862) of the regression tree model shows that the model is sufficient to explain birth weight. Variables of birth year, birth type, sex, herd type and age of dam explained 86.2% of the variation in birth weight.

Association of Maternal Age, Pregnancy Order and Seasonal Variations in Low Birth Weight (LBW) in West Bengal, India

Association of Maternal Age, Pregnancy Order and Seasonal Variations in Low Birth Weight (LBW) in West Bengal, India

Genetic and environmental factors affecting birth size variation: a pooled individual-based analysis of secular trends and global geographical differences using 26 twin cohorts.

The genetic architecture of birth size may differ geographically and over time. We examined differences in the genetic and environmental contributions to birthweight, length and ponderal index (PI) across geographical-cultural regions (Europe, North America and Australia, and East Asia) and across birth cohorts, and how gestational age modifies these effects. Data from 26 twin cohorts in 16 countries including 57613 monozygotic and dizygotic twin pairs were pooled. Genetic and environmental variations of birth size were estimated using genetic structural equation modelling. The variance of birthweight and length was predominantly explained by shared environmental factors, whereas the variance of PI was explained both by shared and unique environmental factors. Genetic variance contributing to birth size was small. Adjusting for gestational age decreased the proportions of shared environmental variance and increased the propositions of unique environmental variance. Genetic variance was similar in the geographical-cultural regions, but shared environmental variance was smaller in East Asia than in Europe and North America and Australia. The total variance and shared environmental variance of birth length and PI were greater from the birth cohort 1990-99 onwards compared with the birth cohorts from 1970-79 to 1980-89. The contribution of genetic factors to birth size is smaller than that of shared environmental factors, which is partly explained by gestational age. Shared environmental variances of birth length and PI were greater in the latest birth cohorts and differed also across geographical-cultural regions. Shared environmental factors are important when explaining differences in the variation of birth size globally and over time.

Pengaruh Asfiksia terhadap Ukuran Kepala Anak Usia 6 Bulan - 2 Tahun di Rumah Sakit Umum Provinsi Nusa Tenggara Barat

Background: In developing countries is estimated at about 120 million babies born asphyxiated at birth. Among these who can survive 20% to 30% had mental disorder, cerebral palsy or developmental abnormality due to the small size of head circumference (microcephaly).Objective: To determine the effect of asphyxia on the head circumference size of children age 6 months - 2 years.Method: A matched case-control study design was conducted from May – June 2014. The population of the study was all children age 6 months - 2 years who visited the Growth development clinic of General Hospital of West Nusa Tenggara Province. The cases were children who have microcephaly and the controls were children with normocephaly. From sample size which was calculated by hypothesis testing two populations proportions are obtained a sample of 72 respondents with 36 cases and 36 controls. Bivariate analysis used chi-square (χ2) McNemar and multivariable analysis with logistic regression (conditional logistic regression) with a significance level of p &lt;0.05 and 95% confidence intervals.Result and Discussion: Microcephaly was present in 83 % of the children with asphyxia, compared with 36 % of the controls. The children with asphyxia tent to have microcephaly compared to children without asphyxia (OR = 5,00; 95% CI: 1,36-18,32). Results of multivariable analysis showed that there was a statistically significant effect between asphyxia with head circumference size by controlling the low birth weight variable (OR = 5,00; 95% CI: 1,36-18,32).Conclusion: History of asphyxia increases the risk of microcephaly compared with non-asphyxia in children aged 6 months - 2 years.Keywords: asphyxia, head circumference, children aged 6 months-2 years

Poids de naissance et transfert d’embryon congelé : état de l’art

The aim of this study was to update our acknowledgment if there is a link between assisted embryo cryopreservation and epigenetics in human? Animal studies have demonstrated epigenetics consequence and especially imprinting disorders due to in vitro culture. In human, it is important to note that after frozen embryo transfer birth weight is significantly increased by 81 to 250g. But these studies cannot identify the reasons of such difference. This review strongly suggests that embryo cryopreservation is responsible for birth weight variations but mechanisms not yet elucidated. Epigenetics is probably one of these but to date, none study is able to prove it. We have to be attentive on a possible link between assisted reproductive technology (ART) and epigenetics reprogrammation.

Genetic Effects for Litter Weight and Within-Litter Birth Weight Variation in a Swine Breeding Population

Genetic Effects for Litter Weight and Within-Litter Birth Weight Variation in a Swine Breeding Population

Association between secondhand smoke exposure and early eruption of deciduous teeth: A cross-sectional study.

INTRODUCTIONSecondhand smoke (SHS) exposure is a risk factor for early childhood caries. Here we examined the association between SHS exposure and early tooth eruption (ETE) to clarify the additional etiology of an increased chance of contact between the tooth’s surface and acid produced by fermenting oral bacteria.METHODSData of 388 child–mother pairs who attended health checkups at public health centers were assessed for children aged ≥18 months. SHS exposure was reported as maternal smoking during pregnancy and household smoking after birth. Associations between SHS exposure and ETE (≥3 canines in the oral cavity) were tested using multivariable analyses of the dose-response relationship. Subgroup and sensitivity analyses were performed for birth-weight subgroups and SHS exposure variables, respectively.RESULTSETE prevalence was 65.5%, 68.1%, and 76.9% in the no, medium-dose (ceased partway and sometimes), and highest-dose (every day) exposure groups, respectively, during pregnancy, and 61.5%, 75.0%, and 75.5%, respectively, after birth. The association between the highest dose exposure during pregnancy and ETE was not significant (OR=1.42, 95% CI: 0.34–5.96, p=0.631), whereas that between highest dose exposure after birth and ETE was significant (OR=2.13, 95% CI: 1.06–4.31, p=0.034); this association was distinct in the subgroup of children with smaller birth weights (<3000 g) (OR=3.19, 95% CI: 1.08–9.44, p=0.036). The dose-response relationship was consistently significant for exposure after birth (p<0.05). The sensitivity analysis that employed no SHS exposure, as a reference, revealed that exposure after birth but no exposure during pregnancy was significantly associated with ETE (OR=2.29, 95% CI: 1.19–4.40, p=0.013). However, the association between exposure during pregnancy and ETE was consistently non-significant (p>0.05).CONCLUSIONSWhen controlling for variables of birth weight and exposure type, SHS exposure after birth was independently associated with the early eruption of deciduous canines. Further studies are warranted to examine the trajectory of SHS exposure after birth, ETE, and early childhood caries incidence.ABBREVIATIONSETE: Early tooth eruption, SHS: Secondhand smoke