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

Factors correlated with physical activity during pregnancy and associations of physical activity with spontaneous abortion, length of gestation, and birthweight

The first study aim was to identify characteristics associated with self-reported physical activity at 17-22 and 27-30 weeks gestation using data from the Pregnancy, Infection, and Nutrition 3 Study. Correlates of low level recreational activity were mostly sociodemographic but most sociodemographics were not also correlated with higher level recreational activity. At 27-30 weeks, overweight/obese women were less likely to engage in recreational activity. At 17-22 weeks, women who began prenatal care later and women with a history of miscarriage were less likely to engage in recreational activity. Physical activity was positively associated with partner support and enjoyment of physical activity. This analysis is limited by self-reported physical activity measures and the performance of model selection based on a p-value. These associations may help target interventions to increase activity during pregnancy. The second aim was to examine the association between vigorous physical activity and gestational age and birthweight (among term births). The third aim was to examine the association between vigorous physical activity and spontaneous abortion. Both aims used data from the Right From the Start Study, which measured vigorous physical activity at 13-16 weeks gestation. The association of total vigorous physical activity with preterm birth was U-shaped. However, vigorous recreational activity was associated with lower odds of preterm birth. Performing at least five sessions of vigorous recreational activity per week was associated with decreased odds of earlier birth (odds ratio (OR) (95% confidence interval, (CI)):0.66 (0.36, 1.21)). Women who reported starting exercise in preparation for pregnancy had lower odds of earlier birth OR(CI): 0.65 (0.45, 0.94), none gave birth preterm. Women who reported decreasing their vigorous activity from pre-pregnancy to interview had lower odds of spontaneous abortion, OR(CI): 0.44 (0.32, 0.61). We found no evidence that vigorous recreational activity was associated with adverse changes in pregnancy outcome. These analyses are limited by self-reported activity measures and low prevalence of vigorous activity. The spontaneous abortion analysis is susceptible to recall bias. Our analysis suggests that vigorous recreational activity during pregnancy may be safe. Future studies should examine the association of vigorous recreational activity with maternal injury and other perinatal outcomes

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

Correlates of Self-Reported Physical Activity at 3 and 12 Months Postpartum

Postpartum women are encouraged to participate in ≥150 minutes/week of moderate-intensity aerobic activity, but few women achieve this recommendation. This study sought to identify factors associated with participation in physical activity following pregnancy

Correlates of Physical Activity at Two Time Points During Pregnancy

Background—Correlates of prenatal physical activity can inform interventions, but are not wellunderstood. Methods—Participants in the Pregnancy, Infection, and Nutrition 3 Study were recruited before 20 weeks gestation. Women self-reported frequency, duration, and mode of moderate and vigorous physical activities. We used logistic regression to identify correlates of any physical activity (≥10 minutes/week of any mode), any recreational activity (≥10 minutes/week), and high volume recreational activity (either ≥150 minutes/week of moderate or ≥75 minutes/week of vigorous). Our analysis included 1752 women at 19-weeks gestation and 1722 at 29 weeks. Results—Higher education, white race, and enjoyment of physical activity were positively correlated with all 3 outcomes. Any recreational activity was negatively associated with parity, body mass index, and history of miscarriage. The associations of history of miscarriage and body mass index differed at 19 weeks compared with 29 weeks. Single marital status, health professional physical activity advice, and time for activity were associated with high volume recreational activity only. Conclusions—Correlates of physical activity differed by mode and volume of activity and by gestational age. This suggests that researchers planning physical activity interventions should consider the mode and amount of activity and the gestational age of the participants

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 COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Offspring birthweight and placental weight—does the type of maternal diabetes matter? A population-based study of 319 076 pregnancies

Introduction Our aim was to estimate the difference in birthweight and in placental weight in pregnancies with type 1 diabetes, type 2 diabetes, and gestational diabetes compared with pregnancies without diabetes. Material and methods By using data from the Medical Birth Registry of Norway during the years 2009–2017, we included 319 076 singleton pregnancies with delivery after the 21st week of pregnancy. We used linear regression analyses to estimate the difference in birthweight and in placental weight in grams (g) in pregnancies with type 1 diabetes, type 2 diabetes, and gestational diabetes, using pregnancies without diabetes as the reference. Adjustments were made for pregnancy duration and pre-pregnancy body mass index. Results In pregnancies without diabetes, mean crude birthweight was 3527 g (SD 552 g). The adjusted mean birthweight was 525 g (95% CI 502–548 g) higher in pregnancies with type 1 diabetes compared with pregnancies without diabetes. In pregnancies with type 2 diabetes, and pregnancies with gestational diabetes, birthweights were 192 g (95% CI 160–223 g) and 102 g (95% CI 93–110 g) higher, respectively. Mean crude placental weight was 664 g (SD 147 g) in pregnancies without diabetes. Compared with pregnancies without diabetes, the adjusted mean placental weight was 109 g (95% CI 101–116 g) higher in pregnancies with type 1 diabetes, 50 g (95% CI 39–60 g) higher in pregnancies with type 2 diabetes, and 31 g (95% CI 28–34 g) higher in pregnancies with gestational diabetes. Conclusions The increase in birthweight and in placental weight associated with maternal diabetes was most pronounced for type 1 diabetes, followed by type 2 diabetes, and gestational diabetes