Cohort Profile Update: Project Viva mothers

Associations of gestation length and offspring birthweight for gestational age with menopausal symptoms and age of natural menopause at midlife among women enrolled in a prebirth longitudinal cohort

OBJECTIVE

Reproductive history may help identify women at higher risk for experiencing menopausal symptoms. We hypothesized that gestation length and offspring birthweight for gestational age z-scores would be associated with menopausal symptoms and age at natural menopause in midlife among women in a longitudinal prebirth cohort.

METHODS

Among 691 women enrolled in pregnancy and followed to midlife, we examined associations of gestation length and offspring birthweight for gestational age z-score at the index pregnancy with total menopausal symptoms assessed with the 11-item Menopause Rating Scale (MRS) using linear regression models, with individual menopausal symptoms using binomial regression models with a log link function, and with age at natural menopause using Cox proportional hazards models. We adjusted all models for age at enrollment, education, parity, annual household income, and prepregnancy body mass index.

RESULTS

Mean (SD) MRS total score was 7.9 (5.8) points at age 52.1 (3.8) years, and mean (SD) age at natural menopause was 50.8 (3.7) years. We observed null associations of gestation length (β = -0.07 points per week, 95% confidence interval [CI] = -0.32 to 0.18) and birthweight for gestational age z-score (β = 0.16 points per z-score, 95% CI = -0.31 to 0.63) with the MRS total score in adjusted models. We also observed null associations of gestation length (adjusted hazards ratio = 0.99 per week, 95% CI = 0.94-1.06) and birthweight for gestational age z-score (adjusted hazards ratio = 1.06 per z-score, 95% CI = 0.94-1.19) with age of onset of natural menopause.

CONCLUSIONS

Birth outcomes were not associated with total menopause symptom scores or age at natural menopause.

Associations of PFAS concentrations during pregnancy and midlife with bone health in midlife: Cross-sectional and prospective findings from Project Viva

BACKGROUND

PFAS may impair bone health, but effects of PFAS exposure assessed during pregnancy and the perimenopause-life stages marked by rapidly changing bone metabolism-on later life bone health are unknown.

METHODS

We studied 531 women in the Boston-area Project Viva cohort. We used multivariable linear, generalized additive, and mixture models to examine associations of plasma PFAS concentrations during early pregnancy [median (IQR) maternal age 32.9 (6.2) years] and midlife [age 51.2 (6.3)] with lumbar spine, total hip, and femoral neck areal bone mineral density (aBMD) and bone turnover biomarkersassessed in midlife. We examined effect modification by diet and physical activity measured at the time of PFAS exposure assessment and by menopausal status in midlife.

RESULTS

Participants had higher PFAS concentrations during pregnancy [1999-2000; e.g., PFOA median (IQR) 5.4 (3.8) ng/mL] than in midlife [2017-2021; e.g.

, PFOA

1.5 (1.2) ng/mL]. Women with higher PFOA, PFOS and PFNA during pregnancy had higher midlife aBMD, especially of the spine [e.g., 0.28 (95% CI: 0.07, 0.48) higher spine aBMD T-score, per doubling of PFOA], with stronger associations observed among those with higher diet quality. In contrast, higher concentrations of all PFAS measured in midlife were associated with lower concurrent aBMD at all sites [e.g., -0.21 (-0.35, -0.07) lower spine aBMD T-score, per doubling of PFOA]; associations were stronger among those who were postmenopausal. The associations of several PFAS with bone resorption (loss) were also stronger among postmenopausal versus premenopausal women.

DISCUSSION

Plasma PFAS measured during pregnancy versus in midlife had different associations with midlife aBMD. We found an adverse association of PFAS measured in midlife with midlife aBMD, particularly among postmenopausal women. Future studies with longer follow-up are needed to elucidate the effect of PFAS on bone health during the peri- and postmenopausal years.

First trimester prenatal metal mixtures, vitamins, and hypertensive disorders of pregnancy in the project viva cohort

BACKGROUND

Hypertensive disorders of pregnancy (HDP) such as preeclampsia and gestational hypertension are major contributors to maternal and child morbidity and mortality. Previous studies have reported associations with selected metals and vitamins but are limited in sample size and non-prospective study designs. We evaluated prospective associations of metal mixtures with HDP and tested interactions by vitamins.

STUDY DESIGN

We measured first trimester (median = 10.1 weeks) concentrations of essential (copper, magnesium, manganese, selenium, zinc) and nonessential (arsenic, barium, cadmium, cesium, mercury, lead) metals in red blood cells (n = 1,386) and vitamins (B12 and folate) in plasma (n = 924) in Project Viva, a pre-birth US cohort. We collected diagnosis of HDP by reviewing medical records. We used multinomial logistic regression and Bayesian Kernel Machine Regression to estimate individual and joint associations of metals with HDP and interactions by vitamins, after adjusting for key covariates.

RESULTS

The majority of participants were non-Hispanic white (72.5 %), never smokers (68.5 %) with a mean (SD) age of 32.3 (4.6) years. Fifty-two (3.8 %) developed preeclampsia and 94 (6.8 %) gestational hypertension. A doubling in first trimester erythrocyte copper was associated with 78 % lower odds of preeclampsia (OR=0.22, 95 % confidence interval: 0.08, 0.60). We also observed significant associations between higher erythrocyte total arsenic and lower odds of preeclampsia (OR=0.80, 95 % CI: 0.66, 0.97) and higher vitamin B12 and increased odds of gestational hypertension (OR=1.79, 95 % CI: 1.09, 2.96), but associations were attenuated after adjustment for dietary factors. Lower levels of the overall metal mixture and essential metal mixture were associated with higher odds of preeclampsia. We found no evidence of interactions by prenatal vitamins or between metals.

CONCLUSION

Lower levels of a first-trimester essential metal mixture were associated with an increased risk of preeclampsia, primarily driven by copper. No associations were observed between other metals and HDP after adjustment for confounders and diet.

History of Infertility and Midlife Cardiovascular Health in Female Individuals

Importance

Fertility status is a marker for future health, and infertility has been associated with risk for later cancer and diabetes, but associations with midlife cardiovascular health (CVH) in female individuals remain understudied.

Objective

To evaluate the association of infertility history with CVH at midlife (approximately age 50 years) among parous individuals.

Design, Setting, and Participants

Project Viva is a prospective cohort study of pregnant participants enrolled between 1999 and 2002 who delivered a singleton live birth in the greater Boston, Massachusetts, area. Infertility history was collected at a midlife visit between 2017 and 2021, approximately 18 years after enrollment. Data analysis was performed from January to June 2023.

Exposures

The primary exposure was any lifetime history of infertility identified by self-report, medical record, diagnosis, or claims for infertility treatment.

Main Outcomes and Measures

The American Heart Association's Life's Essential 8 (LE8) is a construct for ranking CVH that includes scores from 0 to 100 (higher scores denote better health status) in 4 behavioral (diet, physical activity, sleep, and smoking status) and 4 biomedical (body mass index, blood pressure, blood lipids, and glycemia) domains to form an overall assessment of CVH. Associations of a history of infertility (yes or no) with mean LE8 total, behavioral, biomedical, and blood biomarker (lipids and glycemia) scores were examined, adjusting for age at outcome (midlife visit), race and ethnicity, education, household income, age at menarche, and perceived body size at age 10 years.

Results

Of 468 included participants (mean [SD] age at the midlife visit, 50.6 [5.3] years) with exposure and outcome data, 160 (34.2%) experienced any infertility. Mean (SD) LE8 scores were 76.3 (12.2) overall, 76.5 (13.4) for the behavioral domain, 76.0 (17.5) for the biomedical domain, and 78.9 (19.2) for the blood biomarkers subdomain. In adjusted models, the estimated overall LE8 score at midlife was 2.94 points lower (95% CI, -5.13 to -0.74 points), the biomedical score was 4.07 points lower (95% CI, -7.33 to -0.78 points), and the blood subdomain score was 5.98 points lower (95% CI, -9.71 to -2.26 points) among those with vs without history of infertility. The point estimate also was lower for the behavioral domain score (β = -1.81; 95% CI, -4.28 to 0.66), although the result was not statistically significant.

Conclusions and Relevance

This cohort study of parous individuals found evidence for an association between a history of infertility and lower overall and biomedical CVH scores. Future study of enhanced cardiovascular preventive strategies among those who experience infertility is warranted.