16 research outputs found
Impact of female age and nulligravidity on fecundity in an older reproductive age cohort
To provide female age-related estimates of fecundity and incidence of infertility by history of prior pregnancy among women 30 to 44 years of age
Association between serum 25-hydroxyvitamin D and ovarian reserve in premenopausal women
Vitamin D has been linked to anti-Müllerian hormone levels, suggesting a possible association with greater ovarian reserve, but large population-based studies are lacking. Our objective was to explore the association between vitamin D and FSH in premenopausal women
A Prospective Study of the Association Between Vigorous Physical Activity During Pregnancy and Length of Gestation and Birthweight
Current U.S. pregnancy-related physical activity recommendations do not provide specific guidance for vigorous intensity activity. Our objective was to examine the associations between vigorous physical activity during pregnancy and length of gestation and birthweight. Women were recruited before 10 weeks gestation. At 13-16 weeks gestation, participants reported the type, frequency, and duration of their typical weekly vigorous physical activities. Activity domains included recreational, occupational, household, and child/adult care. Infant birth date was obtained from medical or vital records; if unavailable, self-report was used. Birthweight (from vital records) was studied among term births. We analyzed gestational age among 1,647 births using discrete-time survival analysis. We used logistic and linear regression to analyze preterm birth (birth at <37 weeks) and birthweight, respectively. Vigorous recreational activity was associated with longer gestation (any vs. none, hazard ratio (HR) [95% CI]: 0.85 [0.70, 1.05]) and we did not detect any dose-response association. Higher frequency of vigorous recreational activity sessions (adjusted for total volume of activity) was associated with a decreased odds of preterm birth (≥ 4 sessions/week vs. 0 or 1, OR [95% CI]: 0.08 (0.006, 1.0). Birthweight was not associated with physical activity measures. In summary, vigorous physical activity does not appear to be detrimental to the timing of birth or birthweight. Our data support a reduced risk of preterm birth with vigorous recreational activity, particularly with increased frequency of recreational activity sessions. Future studies should investigate the components of physical activity (i.e. intensity, duration, and frequency) in relation to birth outcomes
Normalizing untargeted periconceptional urinary metabolomics data : a comparison of approaches
Metabolomics studies of the early-life exposome often use maternal urine specimens to investigate critical developmental windows, including the periconceptional period and early pregnancy. During these windows changes in kidney function can impact urine concentration. This makes accounting for differential urinary dilution across samples challenging. Because there is no consensus on the ideal normalization approach for urinary metabolomics data, this study’s objective was to determine the optimal post-analytical normalization approach for untargeted metabolomics analysis from a periconceptional cohort of 45 women. Urine samples consisted of 90 paired pre- and post-implantation samples. After untargeted mass spectrometry-based metabolomics analysis, we systematically compared the performance of three common approaches to adjust for urinary dilution—creatinine adjustment, specific gravity adjustment, and probabilistic quotient normalization (PQN)—using unsupervised principal components analysis, relative standard deviation (RSD) of pooled quality control samples, and orthogonal partial least-squares discriminant analysis (OPLS-DA). Results showed that creatinine adjustment is not a reliable approach to normalize urinary periconceptional metabolomics data. Either specific gravity or PQN are more reliable methods to adjust for urinary concentration, with tighter quality control sample clustering, lower RSD, and better OPLS-DA performance compared to creatinine adjustment. These findings have implications for metabolomics analyses on urine samples taken around the time of conception and in contexts where kidney function may be altered
Urinary paraben concentrations and associations with the periconceptional urinary metabolome : untargeted and targeted metabolomics analyses of participants from the early pregnancy study
BACKGROUND: Parabens, found in everyday items from personal care products to foods, are chemicals with endocrine-disrupting activity, which has been shown to influence reproductive function. OBJECTIVES: This study investigated whether urinary concentrations of methylparaben, propylparaben, or butylparaben were associated with the urinary metabolome during the periconceptional period, a critical window for female reproductive function. Changes to the periconceptional urinary metabolome could provide insights into the mechanisms by which parabens could impact fertility. METHODS: Urinary paraben concentrations were measured in paired pre- and postconception urine samples from 42 participants in the Early Pregnancy Study, a prospective cohort of 221 women attempting to conceive. We performed untargeted and targeted metabolomics analyses using ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry. We used principal component analysis, orthogonal partial least-squares discriminant analysis, and permutation testing, coupled with univariate statistical analyses, to find metabolites associated with paraben concentration at the two time points. Potential confounders were identified with a directed acyclic graph and used to adjust results with multivariable linear regression. Metabolites were identified using fragmentation data. RESULTS: Seven metabolites were associated with paraben concentration (variable importance to projection score formula presented , false discovery rate-corrected formula presented ). We identified four diet-related metabolites to the Metabolomics Standards Initiative (MSI) certainty of identification level 2, including metabolites from smoke flavoring, grapes, and olive oil. One metabolite was identified to the class level only (MSI level 3). Two metabolites were unidentified (MSI level 4). After adjustment, three metabolites remained associated with methylparaben and propylparaben, two of which were diet-related. No metabolomic markers of endocrine disruption were associated with paraben concentrations. DISCUSSION: This study identified novel relationships between urinary paraben concentrations and diet-related metabolites but not with metabolites on endocrine-disrupting pathways, as hypothesized. It demonstrates the feasibility of integrating untargeted metabolomics data with environmental exposure information and epidemiological adjustment for confounders. The findings underscore a potentially important connection between diet and paraben exposure, with applications to nutritional epidemiology and dietary exposure assessment
Impact of female age and nulligravidity on fecundity in an older reproductive age cohort
To provide female age-related estimates of fecundity and incidence of infertility by history of prior pregnancy among women 30 to 44 years of age
Circulating miRNAs in the First Trimester and Pregnancy Complications: a Systematic Review
Most pregnancy complications originate with early placentation. MicroRNAs (miRNAs) may play an important role in placentation and function as biomarkers of future pregnancy complications. We summarized from the literature all first trimester circulating miRNAs associated with pregnancy complications of placental origin and further identified the miRNAs which have the most evidence as potential early biomarkers for pregnancy complications. We conducted a systematic review following PRISMA reporting guidelines (PROSPERO CRD42020183421). We identified all first trimester serum or plasma miRNAs associated with a pregnancy complication of placental origin (preeclampsia, intrauterine growth restriction (IUGR), gestational hypertension, preterm delivery) and the number of times those miRNAs were identified, as a measure of replication. Twenty-one studies examined 118 unique miRNAs, and 87 were associated with at least one pregnancy complication; preeclampsia was the most common. Seven miRNAs were significantly associated with a pregnancy complication in at least two studies: miR-125b, miR-518b, miR-628-3p, miR-365a-3p, miR-520h, miR-374a-5p, miR-191-5p. Few miRNAs were associated with more than one pregnancy complication: miR-518b and miR-520h with preeclampsia and gestational hypertension, miR-374a-5p and miR-191-5p with preterm birth and preeclampsia. Our systematic review suggests seven miRNAs as potential biomarkers of pregnancy complications. These complications are thought to originate with early placental defects and these miRNAs may also be biomarkers of placental pathology. First-trimester biomarkers of pregnancy complications can facilitate early detection and interventions
Circulating miRNAs in the first trimester and pregnancy complications: a systematic review
Most pregnancy complications originate with early placentation. MicroRNAs (miRNAs) may play an important role in placentation and function as biomarkers of future pregnancy complications. We summarized from the literature all first trimester circulating miRNAs associated with pregnancy complications of placental origin and further identified the miRNAs which have the most evidence as potential early biomarkers for pregnancy complications. We conducted a systematic review following PRISMA reporting guidelines (PROSPERO CRD42020183421). We identified all first trimester serum or plasma miRNAs associated with a pregnancy complication of placental origin (preeclampsia, intrauterine growth restriction (IUGR), gestational hypertension, preterm delivery) and the number of times those miRNAs were identified, as a measure of replication. Twenty-one studies examined 118 unique miRNAs, and 87 were associated with at least one pregnancy complication; preeclampsia was the most common. Seven miRNAs were significantly associated with a pregnancy complication in at least two studies: miR-125b, miR-518b, miR-628-3p, miR-365a-3p, miR-520h, miR-374a-5p, miR-191-5p. Few miRNAs were associated with more than one pregnancy complication: miR-518b and miR-520h with preeclampsia and gestational hypertension, miR-374a-5p and miR-191-5p with preterm birth and preeclampsia. Our systematic review suggests seven miRNAs as potential biomarkers of pregnancy complications. These complications are thought to originate with early placental defects and these miRNAs may also be biomarkers of placental pathology. First-trimester biomarkers of pregnancy complications can facilitate early detection and interventions
Maternal concentrations of human chorionic gonadotropin (hCG) and risk for cerebral palsy (CP) in the child. A case control study
Background
Intrauterine conditions may be important in the development of cerebral palsy in the child. The hormone, human chorionic gonadotropin (hCG), is synthesized in the placenta, and hCG plays an important role in placental angiogenesis and development. Thus, maternal hCG concentrations may be an indicator of placental function and thereby the intrauterine environment for the offspring. We studied the associations of maternal concentrations of hCG during pregnancy with cerebral palsy in the child.
Methods
We performed a case-control study nested within a cohort of 29,948 pregnancies in Norway during 1992–1994. Cases were all women within the cohort who gave birth to a singleton child with cerebral palsy diagnosed before five years of age (n = 63). Controls were a random sample of women with a singleton child without cerebral palsy (n = 182).
Results
The adjusted odds ratio (OR) for cerebral palsyin the child was 0.78 (95% CI: 0.55–1.10) per log-transformed unit of maternal hCG in the 1 st trimester, and the OR was 1.42 (95% CI: 0.94–2.16) in the 2nd trimester. Thus, women who did not have high hCG concentrations in the 1 st trimester and low hCG concentrations in the 2nd trimester, had increased risk for giving birth to a child with cerebral palsy. Adjustments were made for pregnancy week of serum sampling, maternal age and parity.
Conclusions
The abnormal hCG concentrations in pregnancies with cerebral palsy in the offspring, could suggest placental factors as causes of cerebral palsy
Maternal concentrations of human chorionic gonadotropin (hCG) and risk for cerebral palsy (CP) in the child. A case control study
Background: Intrauterine conditions may be important in the development of cerebral palsy in the child. The hormone, human chorionic gonadotropin (hCG), is synthesized in the placenta, and hCG plays an important role in placental angiogenesis and development. Thus, maternal hCG concentrations may be an indicator of placental function and thereby the intrauterine environment for the offspring. We studied the associations of maternal concentrations of hCG during pregnancy with cerebral palsy in the child.
Methods: We performed a case-control study nested within a cohort of 29,948 pregnancies in Norway during 1992–1994. Cases were all women within the cohort who gave birth to a singleton child with cerebral palsy diagnosed before five years of age (n = 63). Controls were a random sample of women with a singleton child without cerebral palsy (n = 182).
Results: The adjusted odds ratio (OR) for cerebral palsyin the child was 0.78 (95% CI: 0.55–1.10) per log-transformed unit of maternal hCG in the 1 st trimester, and the OR was 1.42 (95% CI: 0.94–2.16) in the 2nd trimester. Thus, women who did not have high hCG concentrations in the 1 st trimester and low hCG concentrations in the 2nd trimester, had increased risk for giving birth to a child with cerebral palsy. Adjustments were made for pregnancy week of serum sampling, maternal age and parity.
Conclusions: The abnormal hCG concentrations in pregnancies with cerebral palsy in the offspring, could suggest placental factors as causes of cerebral palsy