Stefanie N. Hinkle

Effect of male and female body mass index on pregnancy and live birth success after in vitro fertilization

OBJECTIVE To assess the effects of both male and female body mass index (BMI), individually and combined, on IVF outcomes. DESIGN Prospective cohort study. SETTING University fertility center. PATIENT(S) All couples undergoing first fresh IVF cycles, 2005-2010, for whom male and female weight and height information were available (n = 721 couples). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Embryologic parameters, clinical pregnancy, and live birth incidence. RESULT(S) The average male BMI among the study population was 27.5 ± 4.8 kg/m(2) (range, 17.3-49.3 kg/m(2)), while the average female BMI (n = 721) was 25.2 ± 5.9 kg/m(2) (range, 16.2-50.7 kg/m(2)). Neither male nor female overweight (25-29.9 kg/m(2)), class I obese (30-34.9 kg/m(2)), or class II/III obese (≥35 kg/m(2)) status was significantly associated with fertilization rate, embryo score, or incidence of pregnancy or live birth compared with normal weight (18.5-24.9 kg/m(2)) status after adjusting for male and female age, partner BMI, and parity. Similar null findings were found between combined couple BMI categories and IVF success. CONCLUSION(S) Our findings support the notion that weight status does not influence fecundity among couples undergoing infertility treatment. Given the limited and conflicting research on BMI and pregnancy success among IVF couples, further research augmented to include other adiposity measures is needed.

Maternal Prepregnancy Body Mass Index and Child Psychosocial Development at 6 Years of Age

BACKGROUND: Both obesity and developmental disabilities have increased in recent decades. Limited studies suggest associations between maternal prepregnancy obesity and child neurodevelopment. METHODS: The Infant Feeding Practices Study II, a US nationally distributed longitudinal study of maternal health and infant health and feeding practices, was conducted from 2005 to 2007. In 2012, mothers were recontacted for information on their children’s health and development. We examined associations between maternal prepregnancy BMI and child psychosocial development in 1311 mother–child pairs included in this follow-up study. Children’s development was assessed by maternal report of child psychosocial difficulties from the Strengths and Difficulties Questionnaire, past developmental diagnoses, and receipt of special needs services. RESULTS: Adjusting for sociodemographic factors, children of obese class II/III mothers (BMI >35.0) had increased odds of emotional symptoms (adjusted odds ratio [aOR] 2.24; 95% confidence interval [CI], 1.27–3.98), peer problems (aOR 2.07; 95% CI, 1.26–3.40), total psychosocial difficulties (aOR 2.17; 95% CI, 1.24–3.77), attention-deficit/hyperactivity disorder diagnosis (aOR 4.55; 95% CI, 1.80–11.46), autism or developmental delay diagnosis (aOR 3.13; 95% CI, 1.10–8.94), receipt of speech language therapy (aOR 1.93; 95% CI, 1.18–3.15), receipt of psychological services (aOR 2.27; 95% CI, 1.09–4.73), and receipt of any special needs service (aOR 1.99; 95% CI, 1.33–2.97) compared with children of normal weight mothers (BMI 18.5–24.9). Adjustment for potential causal pathway factors including pregnancy weight gain, gestational diabetes, breastfeeding duration, postpartum depression, and child’s birth weight did not substantially affect most estimates. CONCLUSIONS: Children whose mothers were severely obese before pregnancy had increased risk for adverse developmental outcomes.

Changes in diabetes status between pregnancies and impact on subsequent newborn outcomes

OBJECTIVE Pregnancies complicated by gestational diabetes mellitus (GDM) or preexisting diabetes mellitus (DM) are at high risk for adverse newborn outcomes. Whether GDM history, recurrence, or transition to DM modifies such risks is unknown. STUDY DESIGN Medical record data on 62,013 repeat singleton pregnancies were collected retrospectively from women who delivered at least twice in Utah (2002 through 2010). Poisson regression models with robust variance estimators were used to estimate relative risks (RR) and 95% confidence intervals (CI) associated with GDM/DM status at the previous and/or current pregnancy relative to those without GDM/DM at either. Large for gestational age (LGA), shoulder dystocia, preterm birth (<37 weeks), respiratory distress syndrome, and other neonatal morbidities were examined adjusting for study site, maternal age, race, parity, interpregnancy interval, prepregnancy body mass index, and smoking status. RESULTS GDM in the previous pregnancy alone increased the risk of LGA in the current pregnancy (RR, 1.20; 95% CI, 1.05-1.38). Recurrent GDM increased the risks of LGA (RR, 1.76; 95% CI, 1.56-1.98), shoulder dystocia (RR, 1.98; 95% CI, 1.46-2.70), and preterm birth (RR, 1.68; 95% CI, 1.44-1.96) beyond that observed for pregnancies with current GDM alone. Women with GDM in a previous pregnancy that transitioned to DM in the current pregnancy and women with DM prior to the previous pregnancy had increased risks of all above outcomes. CONCLUSION GDM in a previous pregnancy alone without recurrence may still confer an increased LGA risk. Pregnancies complicated by GDM that transition to DM and those with DM prior to the previous pregnancy have the highest risks of adverse newborn outcomes.

Obstetric and Neonatal Risks Among Obese Women Without Chronic Disease.

OBJECTIVE: To investigate whether prepregnancy obesity is associated with adverse pregnancy outcomes among women without chronic disease. METHODS: Singleton deliveries (N=112,309) among mothers without chronic diseases in the Consortium on Safe Labor, a retrospective U.S. cohort, were analyzed using Poisson regression with robust variance estimation. Relative risks and 95% confidence intervals (CIs) estimated perinatal risks in relation to prepregnancy obesity status adjusted for age, race–ethnicity, parity, insurance, smoking and alcohol use during pregnancy, and study site. RESULTS: Obstetric risks were variably (and mostly marginally) increased as body mass index (BMI) category and obesity class increased. In particular, the risk of gestational hypertensive disorders, gestational diabetes, cesarean delivery, and induction increased in a dose–response fashion. For example, the percentage of gestational diabetes among obese class III women was 14.6% in contrast to 2.8% among women with normal BMIs (corresponding relative risks [95% CI] 1.99 [1.86–2.13], 2.94 [2.73–3.18], 3.97 [3.61–4.36], and 5.47 [4.96–6.04] for overweight, obese class I, obese class II, and obese class III women, respectively) compared with women with normal BMIs. Similarly, neonatal risks increased in a dose–response fashion with maternal BMI status including preterm birth at less than 32 weeks of gestation, large for gestational age (LGA), transient tachypnea, sepsis, and intensive care unit admission. The percentage of LGA neonates increased from 7.9% among women with normal BMIs to 17.3% among obese class III women and relative risks increased to 1.52 (1.45–1.58), 1.74 (1.65–1.83), 1.93 (1.79–2.07), and 2.32 (2.14–2.52) as BMI category increased. CONCLUSION: Prepregnancy obesity is associated with increased risks of a wide range of adverse pregnancy and neonatal outcomes among women without chronic diseases.

Previous prelabor or intrapartum cesarean delivery and risk of placenta previa

OBJECTIVE The purpose of this study was to examine the association between previous cesarean delivery and subsequent placenta previa while distinguishing cesarean delivery before the onset of labor from intrapartum cesarean delivery. STUDY DESIGN We conducted a retrospective cohort study of electronic medical records from 20 Utah hospitals (2002-2010) with restriction to the first 2 singleton deliveries of nulliparous women at study entry (n=26,987). First pregnancy delivery mode was classified as (1) vaginal (reference), (2) cesarean delivery before labor onset (prelabor), or (3) cesarean delivery after labor onset (intrapartum). Risk of second delivery previa was estimated by previous delivery mode with the use of logistic regression and was adjusted for maternal age, insurance, smoking, comorbidities, previous pregnancy loss, and history of previa. RESULTS Most first deliveries were vaginal (82%; n=22,142), followed by intrapartum cesarean delivery (14.6%; n=3931), or prelabor cesarean delivery (3.4%; n=914). Incidence of second delivery previa was 0.29% (n=78) and differed by previous delivery mode: vaginal, 0.24%; prelabor cesarean delivery, 0.98%; intrapartum cesarean delivery, 0.38% (P<.001). Relative to vaginal delivery, previous prelabor cesarean delivery was associated with an increased risk of second delivery previa (adjusted odds ratio, 2.62; 95% confidence interval, 1.24-5.56). There was no significant association between previous intrapartum cesarean delivery and previa (adjusted odds ratio, 1.22; 95% confidence interval, 0.68-2.19). CONCLUSION Previous prelabor cesarean delivery was associated with a >2-fold significantly increased risk of previa in the second delivery, although the approximately 20% increased risk of previa that was associated with previous intrapartum cesarean delivery was not significant. Although rare, the increased risk of placenta previa after previous prelabor cesarean delivery may be important when considering nonmedically indicated prelabor cesarean delivery.

Customized large-for-gestational-age birthweight at term and the association with adverse perinatal outcomes

OBJECTIVE Using a cohort of 110,447 singleton, term pregnancies, we aimed to validate the previously proposed customized standard of large-for-gestational-age (LGA) birthweight, derive an additional customized LGA model excluding maternal weight, and evaluate the association between differing definitions of customized LGA and perinatal morbidities. STUDY DESIGN Three customized LGA classifications, in addition to a population-based 90th percentile, were made according to the principals described by Gardosi: (1) customized LGA using Gardosis previously published coefficients (LGA-Gardosi), (2) customized LGA using coefficients derived by a similar method but from our larger cohort, and (3) derived without customization for maternal weight. Associations between the LGA classifications and various perinatal morbidity outcomes were evaluated. RESULTS Coefficients derived here for physiologic and pathologic effects on birthweight were similar to those previously reported by Gardosi. Customized LGA (any method) generally identified more births to younger, nonwhite, nulliparous mothers with female neonates of lower birthweight compared with population-based LGA. Rates of maternal and neonatal morbidity were greatest in births classified by both population-based LGA and customized LGA (any method). However, the model that excluded customization for maternal weight, revealed a greater proportion of women previously unidentified by population-based LGA who were more frequently black (40% vs 25%) and obese (30% vs 5.1%), along with greater rates of shoulder dystocia, neonatal intensive care unit admission and neonatal respiratory complications, than with LGA-Gardosi. CONCLUSION The use of customized methods of defining LGA was not decisively superior compared with population-based LGA, but custom LGA may be improved by modification of the parameters included in customization.

Differences in risk factors for incident and recurrent small-for-gestational-age birthweight: a hospital-based cohort study

Examine whether small‐for‐gestational‐age (SGA) risk factors differed by prior SGA birth.

Racial/ethnic differences in preterm perinatal outcomes.

Background: Racial disparities in preterm birth and infant death have been well documented. Less is known about racial disparities in neonatal morbidities among infants who are born at <37 weeks of gestation. Objective: The purpose of this study was to determine whether the risk for morbidity and death among infants who are born preterm differs by maternal race. Study Design: A retrospective cohort design included medical records from preterm deliveries of 19,325 black, Hispanic, and white women in the Consortium on Safe Labor. Sequentially adjusted Poisson models with generalized estimating equations estimated racial differences in the risk for neonatal morbidities and death, controlling for maternal demographics, health behaviors, and medical history. Sex differences between and within race were examined. Results: Black preterm infants had an elevated risk for perinatal death, but there was no difference in risk for neonatal death across racial groups. Relative to white infants, black infants were significantly more likely to experience sepsis (9.1% vs 13.6%), peri‐ or intraventricular hemorrhage (2.6% vs 3.3%), intracranial hemorrhage (0.6% vs 1.8%), and retinopathy of prematurity (1.0% vs 2.6%). Hispanic and white preterm neonates had similar risk profiles. In general, female infants had lower risk relative to male infants, with white female infants having the lowest prevalence of a composite indicator of perinatal death or any morbidity across all races (30.9%). Differences in maternal demographics, health behaviors, and medical history did little to influence these associations, which were robust to sensitivity analyses of pregnancy complications as potential underlying mechanisms. Conclusion: Preterm infants were at similar risk for neonatal death, regardless of race; however, there were notable racial disparities and sex differences in rare, but serious, adverse neonatal morbidities.

First trimester coffee and tea intake and risk of gestational diabetes mellitus: a study within a national birth cohort

Coffee and tea consumption is associated with a decreased type 2 diabetes risk in non‐pregnant adults. We examined the relation between first trimester coffee and tea consumption and gestational diabetes mellitus (GDM) risk.

Insulin-Like Growth Factor Axis and Gestational Diabetes Mellitus: A Longitudinal Study in a Multiracial Cohort

The insulin-like growth factor (IGF) axis may be implicated in glucose homeostasis, but its longitudinal profile across gestation in relation to the development of gestational diabetes mellitus (GDM) is largely unknown. We prospectively investigated IGF axis biomarkers in early-to-midpregnancy in relation to subsequent GDM risk in a case-control study of 107 case subjects with GDM and 214 control subjects without GDM, with blood sample collection at gestational weeks 10–14, 15–26, 23–31, and 33–39. Conditional logistic regression was used, adjusting for major risk factors including prepregnancy BMI. Plasma IGF-I and IGF binding protein 3 (IGFBP-3) concentrations and molar ratio of IGF-I to IGFBP-3 increased, whereas IGFBP-2 decreased throughout pregnancy. At gestational weeks 10–14, both IGF-I and IGF-I/IGFBP-3 were positively associated with GDM risk; adjusted odds ratio (OR) comparing the highest versus lowest quartile (ORQ4-Q1) was 2.93 (95% CI 1.18, 7.30) for IGF-I and 3.31 (1.10, 9.98) for IGF-I/IGFBP-3. In contrast, higher IGFBP-2 levels were related to a substantially lower risk of GDM (ORQ4-Q1 0.04 [0.01, 0.06]). Similar results were observed at gestational weeks 15–26. In sum, the IGF axis, IGFBP-2 in particular, may be implicated in the pathogenesis of GDM, with significant associations and incremental predictive value detected as early as gestational weeks 10–14, ∼10–18 weeks earlier before GDM is typically screened for.