Ihunnaya O. Frederick

Correlates of recreational physical activity in early pregnancy

Objective: Despite the well-documented benefits of a physically active lifestyle, over 25% of American adults report that they never engage in regular recreational physical activity. Little is known about the determinants of physical activity among pregnant women. We investigated the predictors of physical activity in 386 normotensive pregnant women. Methods: Participants provided information about the type, frequency and duration of each physical activity performed during the first 20 weeks of pregnancy. We calculated odd ratios (OR) for active compared with inactive women using logistic regression models. Results: Approximately 61% of women reported participating in some regular physical activity during pregnancy. Walking, swimming, gardening and jogging were the most common activities. Physical activity as an adolescent (OR 4.0) and during the year before pregnancy (OR 48.9) were the strongest predictors of physical activity in pregnancy. Active women who continued to exercise during pregnancy decreased the average intensity of their exercise and the weekly duration of exercise compared with the year before pregnancy. Nulliparas were twice as likely to engage in physical activity as compared with multiparas. Education and income were positively related with physical activity. Non-White women were 40-60% less likely to engage in physical activity as compared with White women. Smokers were also less likely to engage in physical activity. High protein intake was positively associated with physical activity, while the opposite was true for high carbohydrate intake. Conclusions: The identification of determinants of physical activity in pregnancy has important implications for developing strategies aimed at promoting a physically active lifestyle among young women.

Glucose intolerance and gestational diabetes risk in relation to sleep duration and snoring during pregnancy: a pilot study

BackgroundInsufficient sleep and poor sleep quality, considered endemic in modern society, are associated with obesity, impaired glucose tolerance and diabetes. Little, however, is known about the consequences of insufficient sleep and poor sleep quality during pregnancy on glucose tolerance and gestational diabetes.MethodsA cohort of 1,290 women was interviewed during early pregnancy. We collected information about sleep duration and snoring during early pregnancy. Results from screening and diagnostic testing for gestational diabetes mellitus (GDM) were abstracted from medical records. Generalized linear models were fitted to derive relative risk (RR) and 95% confidence intervals (95% CIs) of GDM associated with sleep duration and snoring, respectively.ResultsAfter adjusting for maternal age and race/ethnicity, GDM risk was increased among women sleeping ≤ 4 hours compared with those sleeping 9 hours per night (RR = 5.56; 95% CI 1.31-23.69). The corresponding RR for lean women (<25 kg/m2) was 3.23 (95% CI 0.34-30.41) and 9.83 (95% CI 1.12-86.32) for overweight women (≥ 25 kg/m2). Overall, snoring was associated with a 1.86-fold increased risk of GDM (RR = 1.86; 95% CI 0.88-3.94). The risk of GDM was particularly elevated among overweight women who snored. Compared with lean women who did not snore, those who were overweight and snored had a 6.9-fold increased risk of GDM (95% CI 2.87-16.6).ConclusionsThese preliminary findings suggest associations of short sleep duration and snoring with glucose intolerance and GDM. Though consistent with studies of men and non-pregnant women, larger studies that include objective measures of sleep duration, quality and apnea are needed to obtain more precise estimates of observed associations.

Increased maternal plasma leptin in early pregnancy and risk of gestational diabetes mellitus.

OBJECTIVE: Emerging evidence suggests that leptin, an adipocyte-derived hormone, may have independent direct effects on both insulin secretion and action, in addition to its well documented effects on appetite and energy expenditure. Some, but not all, previously published studies suggest that maternal leptin concentrations may be increased in pregnancies complicated by gestational diabetes mellitus (GDM). We examined the association between plasma leptin concentration and GDM risk. METHODS: Women were recruited before 16 weeks of gestation and were followed up until delivery. Maternal plasma leptin concentrations (collected at 13 weeks of gestation) were measured by using immunoassay. We used generalized linear models to estimate relative risks and 95% confidence intervals. RESULTS: GDM developed in 5.7% of the cohort (47 of 823). Elevated leptin concentrations were positively associated with GDM risk (P for trend < .001). After adjusting for maternal prepregnancy adiposity and other confounders, women with leptin concentrations of 31.0 ng/mL or higher experienced a 4.7-fold increased risk of GDM (95% confidence interval 1.2, 18.0) as compared with women who had concentrations of 14.3 ng/mL or lower. We noted a strong linear component of trend in risk of GDM with increasing maternal plasma leptin concentration. Each 10-ng/mL increase in the leptin concentration was associated with a 20% increase in GDM risk (relative risk 1.2; 95% confidence interval 1.0, 1.3). CONCLUSIONS: Hyperleptinemia, independent of maternal adiposity, in early pregnancy appears to be predictive of an increased risk of GDM later in pregnancy. Additional larger prospective cohort studies are needed to confirm and more precisely assess the etiologic importance of hyperleptinemia in pregnancy. LEVEL OF EVIDENCE: II-2

Family History of Hypertension and Type 2 Diabetes in Relation to Preeclampsia Risk

Abstract—In a case-control study of 190 preeclamptic patients and 373 control subjects, we assessed maternal family history of chronic hypertension and type 2 diabetes in relation to preeclampsia risk. Participants provided information on first-degree family history of the 2 conditions and other covariates during postpartum interviews. Logistic regression was used to estimate odds ratios and 95% confidence intervals adjusted for confounding by age, race, and obesity. Compared with women with no parental history of hypertension, women with maternal only (odds ratio=1.9), paternal only (odds ratio=1.8), or both maternal and paternal history of hypertension (odds ratio=2.6) had a statistically significant increased risk of preeclampsia. The odds ratio for women with at least one hypertensive parent and a hypertensive sibling was 4.7 (95% confidence interval, 1.9 to 11.6). Both maternal only (odds ratio=2.1; 95% confidence interval, 0.9 to 4.6) and paternal only (odds ratio=1.9; 95% confidence interval, 1.0 to 3.2) history of diabetes was associated with an increased risk of preeclampsia. Women with a diabetic sibling had a 4.7-fold increased risk of preeclampsia (95% confidence interval, 1.1 to 19.8). For women with at least one hypertensive parent and at least one diabetic parent, relative to those with parents with neither diagnosis, the odds ratio for preeclampsia was 3.2 (95% confidence interval, 1.6 to 6.2). Our results are consistent with the thesis that family history of hypertension and diabetes reflects genetic and behavioral factors whereby women may be predisposed to an increased preeclampsia risk.

Vitamin C and the risk of preeclampsia-results from dietary questionnaire and plasma assay

Background. Oxidative stress plays an important role in the pathophysiology of preeclampsia. Methods. In a case-control study of 109 women with preeclampsia and 259 controls, maternal dietary and plasma vitamin C in relation to preeclampsia risk were assessed. Dietary intake during the periconceptional period and pregnancy was ascertained using a semiquantitative food frequency questionnaire. Logistic regression procedures were used to derive odds ratios (OR) and 95% confidence intervals (CI). Plasma ascorbic acid was determined using automated enzymatic procedures. Results. After adjusting for maternal age, parity, prepregnancy body mass index, and energy intake, women who consumed <85 mg of vitamin C daily (below the recommended dietary allowance), as compared with others, experienced a doubling in preeclampsia risk (OR = 2.1; 95% CI = 1.1–3.9). The OR for extreme quartiles of plasma ascorbic acid (<42.5 vs ≥ 63.3 &mgr;mol/liter) was 2.3 (95% CI = 1.1–4.6). Compared with women in the highest quartile, those with plasma ascorbic acid <34.6 &mgr;mol/liter (lowest decile) experienced a 3.8-fold increased risk of preeclampsia (95% CI = 1.7–8.8). Conclusions. Our results, if confirmed, would suggest that current public health efforts to increase intake of fruits and vegetables rich in vitamin C and other antioxidants may reduce the risk of preeclampsia.

Gestational Diabetes Mellitus in Relation to Maternal Dietary Heme Iron and Nonheme Iron Intake

OBJECTIVE Higher heme iron intake is associated with increased type 2 diabetes risk. However, no previous study has evaluated gestational diabetes mellitus (GDM) risk in relation to heme iron intake during pregnancy. We investigated associations of maternal preconceptional and early pregnancy heme and nonheme iron intake with subsequent GDM risk. RESEARCH DESIGN AND METHODS We conducted a prospective cohort study of 3,158 pregnant women. A food frequency questionnaire was used to assess maternal diet. Multivariable generalized linear regression models were used to derive estimates of relative risks (RRs) and 95% CIs. RESULTS Approximately 5.0% of the cohort developed GDM (n = 158). Heme iron intake was positively and significantly associated with GDM risk (Ptrend = 0.04). After adjusting for confounders, women reporting the highest heme iron intake levels (≥1.52 vs. <0.48 mg per day) experienced a 3.31-fold–increased GDM risk (95% CI 1.02–10.72). In fully adjusted models, we noted that a 1-mg per day increase in heme iron was associated with a 51% increased GDM risk (RR 1.51 [95% CI 0.99–2.36]). Nonheme iron was inversely, though not statistically significantly, associated with GDM risk, and the corresponding RRs were 1.00, 0.83, 0.62, and 0.61 across quartiles of nonheme iron intake (Ptrend = 0.08). CONCLUSIONS High levels of dietary heme iron intake during the preconceptional and early pregnancy period may be associated with increased GDM risk. Associations of GDM risk with dietary nonheme iron intake are less clear. Confirmation of these findings by future studies is warranted.

Dietary Fiber Intake in Early Pregnancy and Risk of Subsequent Preeclampsia

BACKGROUND Substantial epidemiological evidence documents diverse health benefits, including reduced risks of hypertension, associated with diets high in fiber. Few studies, however, have investigated the extent to which dietary fiber intake in early pregnancy is associated with reductions in preeclampsia risk. We assessed the relationship between maternal dietary fiber intake in early pregnancy and risk of preeclampsia. We also evaluated cross-sectional associations of maternal early pregnancy plasma lipid and lipoprotein concentrations with fiber intake. METHODS The study population comprised 1,538 pregnant Washington State residents. A 121-item food frequency questionnaire (FFQ) was used to assess maternal dietary intake, 3 months before and during early pregnancy; and generalized linear regression procedures were used to derive relative risk (RR) and 95% confidence intervals (CIs). RESULTS Dietary total fiber intake was associated with reduced preeclampsia risk. After adjusting for confounders, the RR of preeclampsia for women in the highest (> or =21.2 g/day) vs. the lowest quartile (<11.9 g/day) was 0.28 (95% CI = 0.11-0.75). We observed associations of similar magnitude when the highest vs. the lowest quartiles of water-soluble fiber (RR = 0.30; 95% CI = 0.11-0.86) and insoluble fiber (RR = 0.35; 95% CI = 0.14-0.87) were evaluated. Mean triglyceride concentrations were lower (-11.9 mg/dl, P = 0.02) and high-density lipoprotein cholesterol concentrations were higher (+2.63 mg/dl, P = 0.09) for women in the highest quartile vs. those in the lowest quartile. CONCLUSIONS These findings of reduced preeclampsia risk with higher total fiber intake corroborate an earlier report; and expand the literature by providing evidence, which suggests that dietary fiber may attenuate pregnancy-associated dyslipidemia, an important clinical characteristic of preeclampsia.

Adult Weight Change, Weight Cycling, and Prepregnancy Obesity in Relation to Risk of Preeclampsia

Background: Preeclampsia has been shown to be associated with obesity, with other risk factors for cardiovascular disease, and with subsequent cardiovascular disease itself. However, the possible association with weight gain and weight cycling has not been evaluated. Methods: In this prospective study of a cohort of 1644 pregnant women, we assessed adult weight change, intentional weight cycling, and prepregnancy obesity in relation to preeclampsia risk. Net weight change from age 18 years to the period 3 months before conception was determined for each participant. Weight cycling was defined as intentional weight loss and unintentional regain of at least 15 pounds during periods not related to pregnancy or lactation. We used multivariate regression procedures to calculate risk ratios (RRs) and 95% confidence intervals (CIs). Results: Relative to women with stable weight (gained or lost <2.5 kg) women who gained 5.0–9.9 kg experienced a 2.6-fold increased risk of preeclampsia (95% CI = 1.0–6.7). The corresponding risk ratio (RR) for women who gained ≥10 kg was 5.1 (2.2–12.2). Intentional weight cycling, after controlling for weight at age 18 years, adult weight change, and other risk factors, was not associated with increased risk of preeclampsia (RR = 1.1; CI = 0.6–1.8). RRs increased monotonically with increasing prepregnancy body mass index greater than 19.8 kg/m2. After adjusting for confounders, the RR for prepregnancy overweight women and obese women were 1.7 (0.6–4.9) and 3.4 (1.5–7.6) respectively. Conclusions: These results suggest that adult weight gain and prepregnancy overweight and obesity status are associated with an increased risk of preeclampsia.

Maternal asthma and risk of preterm delivery.

PURPOSE We studied the relation between maternal history of asthma and preterm delivery. METHODS The 312 preterm delivery cases, studied in aggregate, and in subgroups (spontaneous preterm labor, preterm premature rupture of membranes, medically induced preterm delivery), were compared with 424 randomly selected women who delivered at term. Maternal medical records provided information on maternal lifetime asthma status, pregnancy outcome, and sociodemographic characteristics. Using multivariate logistic regression, we derived maximum likelihood estimates of adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS Maternal history of asthma was associated with an increased risk of preterm delivery overall (OR = 2.37; 95% CI 1.15-4.88). Analyses of preterm delivery sub-groups indicated that maternal history of asthma was associated with at least a doubling in risk of spontaneous preterm labor (OR = 2.35; 95% CI 0.84-6.58) and medically induced preterm delivery (OR = 2.69; 95% CI 1.11-6.53), though only the latter approached statistical significance. There was some evidence of a modest association between maternal asthma and risk of preterm premature rupture of membranes (OR = 1.63; 95% CI 0.50-5.33). CONCLUSIONS These results support the hypothesis that maternal asthma is associated with an increased risk of preterm labor and delivery.

Risk of preterm delivery and hypertensive disorders of pregnancy in relation to maternal co-morbid mood and migraine disorders during pregnancy

We evaluated the risks of preterm delivery and hypertensive disorders of pregnancy among pregnant women with mood and migraine disorders, using a cohort study of 3432 pregnant women. Maternal pre-pregnancy or early pregnancy (<20 weeks gestation) mood disorder and pre-pregnancy migraine diagnoses were ascertained from interview and medical record review. We fitted generalised linear models to derive risk ratios (RR) and 95% confidence intervals (CI) of preterm delivery and hypertensive disorders of pregnancy for women with isolated mood, isolated migraine and co-morbid mood-migraine disorders, respectively. Reported RR were adjusted for maternal age, race/ethnicity, marital status, parity, smoking status, chronic hypertension or pre-existing diabetes mellitus, and pre-pregnancy body mass index. Women without mood or migraine disorders were defined as the reference group. The risks for preterm delivery and hypertensive disorders of pregnancy were more consistently elevated among women with co-morbid mood-migraine disorders than among women with isolated mood or migraine disorder. Women with co-morbid disorders were almost twice as likely to deliver preterm (adjusted RR=1.87, 95% CI 1.05, 3.34) compared with the reference group. There was no clear evidence of increased risks of preterm delivery and its subtypes with isolated migraine disorder. Women with mood disorder had elevated risks of pre-eclampsia (adjusted RR=3.57, 95% CI 1.83, 6.99). Our results suggest an association between isolated migraine disorder and pregnancy-induced hypertension (adjusted RR=1.42, 95% CI 1.00, 2.01). This is the first study examining perinatal outcomes in women with co-morbid mood-migraine disorders. Pregnant women with a history of migraine may benefit from screening for depression during prenatal care and vigilant monitoring, especially for women with co-morbid mood and migraine disorders.