Pregnancy BMI - Pregnancy BMI Resources Resources

Objective: The purpose of this study was to evaluate the relationship between prepregnancy maternal body mass index and spontaneous preterm birth and indicated preterm birth. Study design: This was a secondary analysis of the Maternal-Fetal Medicine Units Network, Preterm Prediction study. Patients were classified into categories that were based on their body mass index. Rates of indicated and spontaneous preterm birth were compared. Results: Five hundred ninety-seven (20.5%) of 2910 women were obese. Obese women had fewer spontaneous preterm births at !37 weeks of gestation (6.2% vs 11.2%; P ! .001) and at !34 weeks of gestation (1.5% vs 3.5%; P =.012). Women with a body mass index of !19 kg/m2 had 16.6% spontaneous preterm birth, with a body mass index of 19 to 24.9 kg/m2 had 11.3% spontaneous preterm birth, with a body mass index of 25 to 29.9 kg/m2 had 8.1% spontaneous preterm birth, with a body mass index of 30 to 34.9 kg/m2 had 7.1% spontaneous preterm birth, and with a body mass index of R35 kg/m2 had 5.2% spontaneous preterm birth (P ! .0001). Indicated delivery was responsible for an increasing proportion of preterm births with increasing body mass index (P= .001). Obese women had lower rates of cervical length !25 mm (5% vs 8%; P =.012). Multivariable regression analysis confirmed a lower rate of spontaneous preterm birth in obese gravid women (odds ratio, 0.57; 95% CI, 0.39-0.83; P =.003). Conclusion: Obesity before pregnancy is associated with a lower rate of spontaneous preterm birth.

Objective: To assess whether advanced maternal age modifies the relationship between maternal pregravid weight status, gestational weight gain patterns, and the occurrence of spontaneous preterm birth (SPB) and medically indicated preterm birth (MIPB). Methods: Retrospective cohort analysis of vital statistics data from the state of Florida for the period 2004 through 2007 comprising 311,422 singleton pregnancies (two age groups: 20–24 years old or younger women and ≥35 years or older women). Mothers were classified into five clusters based on their prepregnancy body mass index (BMI) values: non-obese (less than 30), class I obese (30.0≤BMI≤34.9), class II obese (35.0≤BMI≤39.9), class III obese (40≤BMI≤49.9), and super-obese (BMI≥50.0). Results: MIPB occurred more frequently among older than younger women [11.8% vs. 6.4%, respectively (p < 0.0001)) whereas SPB occurred more frequently among youngerwomen[11.3% vs. 10.5%, respectively (p < 0.0001)). Maternal obesity increased the risk forMIPBbut not for SPB. Regardless ofBMIstatus, the risk of MIPB was elevated among older mothers, particularly among those with suboptimal (<0.23 kg/week) and supraoptimal (>0.68 kg/week) gestational weight gain. A dose–response relationship with increasing gestational weight gain was evident (p < 0.01); the greatest risk for MIPB occurred among older mothers with weekly gestational weight gain in excess of 0.79 kg (OR = 7.76, 95% CI = 5.73–10.5). Conclusion: The occurrence of medically indicated preterm birth is positively associated with increased maternal pregravid body weight, older maternal age and extremes of gestational weight gain. Targeted pre- and inter-conception weight management efforts should be particularly encouraged in older mothers.

OBJECTIVE: The purpose of this study was to examine the association between gestational weight gain (GWG) in a woman’s first and second pregnancies. STUDY DESIGN: We conducted a retrospective observational cohort study of 27,771 women with their first and second births in North Carolina’s Pregnancy Nutrition Surveillance System database from 1996-2004. GWG was categorized as inadequate, appropriate, or excessive, according to 2009 Institute of Medicine guidelines. Covariate adjusted polytomous logistic regression was used to test the association between GWG category in the first and second pregnancy. RESULTS: Compared with women with appropriate GWG in their first pregnancy, women with excessive GWG in their first pregnancy had an odds ratio of 2.6 (95% confidence interval, 2.4 –2.7) for excessive GWG in their second pregnancy. Women with inadequate GWG in their first pregnancy were similarly likely to repeat this category in their subsequent pregnancy. CONCLUSION: GWG category in a woman’s first pregnancy is a significant predictor of GWG category in her subsequent pregnancy.

OBJECTIVE: To estimate the effect of maternal habitus on detection of fetuses with major structural anomalies during second-trimester standard and targeted ultrasound examinations. METHODS: This was a retrospective cohort study of pregnancies 18 to 24 weeks that underwent ultrasonography over a 5-year period. An anomalous fetus was considered detected if a major abnormality of the relevant organ system was identified, regardless of the anticipated ultrasound detection. Anomalies were verified using a prospectively maintained database. Body mass index (BMI) was based on weight at first prenatal visit. RESULTS: There were 10,112 standard examinations in low-risk pregnancies and 1,098 targeted examinations in pregnancies with either high-risk indications or with an abnormality detected during standard ultrasonography. Detection of anomalous fetuses decreased with increasing BMI. For normal BMI, overweight, and class I, II, and III obesity, detection with standard ultrasonography was 66%, 49%, 48%, 42%, and 25%, respectively, and with targeted ultrasonography, 97%, 91%, 75%, 88%, and 75%, respectively, both P<.03. Residual anomaly risk after a normal ultrasound examination increased with increasing BMI, from 0.4% among women of normal BMI to 1.0% among obese women, P
.001. Anomaly detection was lower among women with pregestational diabetes than in those with other high-risk indications, 38% compared with 88% respectively, P<.001. CONCLUSION: With increasing maternal BMI, we found decreased detection of anomalous fetuses with either standard or targeted ultrasonography, a difference of at least 20% when women of normal BMI were compared with obese women. Anomaly detection was even less in pregnancies complicated by pregestational diabetes. Counseling may need to be modified to reflect the limitations of ultrasonography in obese women.

ABSTRACT: The prevalence of obesity is currently rising in developed countries, making pregravid overweight one of the most common high-risk obstetric situations. Although the designs and populations of published studies vary widely, most authors agree that pregravid overweight increases maternal and fetal morbidity. Even moderate overweight is a risk factor for gestational diabetes and hypertensive disorders of pregnancy,and the risk is higher in subjects with overt obesity. Compared with normal weight, maternal overweight is related to a higher risk of cesarean deliveries and a higher incidence of anesthetic and postoperative complications in these deliveries. Low Apgar scores, macrosomia, and neural tube defects are more frequent in infants of obese mothers than in infants of normal-weight mothers. The regional distribution of fat modulates the effects of weight on carbohydrate tolerance, hemodynamic adaptation, and fetal size. Maternal obesity increases perinatal mortality. Longterm complications include worsening of maternal obesity and development of obesity in the infant. The average cost of hospital prenatal and postnatal care is higher for overweight mothers than for normal-weight mothers, and infants of overweight mothers require admission to neonatal intensive care units more often than do infants of normal-weight mothers. Preconception counseling, careful prenatal management, tight monitoring of weight gain, and long-term follow-up could minimize the social and economic consequences of pregnancies in overweight women.

Objective: To explore the association between striae gravidarum (SG) and the risk for perineal trauma (PT) in childbirth. Design: A cross-sectional study. Setting: Maternity ward in 5 university medical centers. Participants: Three hundred and eighty-five women (28.9  5.3 years old) who delivered vaginally. Methods: Striae gravidarum score was assessed using the Atwal numerical scoring system. The association was examined between PT as the outcome measure, defined by tears or laceration, and the total striae scores (TSS) obtained at the abdomen, hips, buttocks, and breast. Results: Significantly higher TSS scores were found in women with PT compared with women without PT (3.60  0.39 vs. 2.31  0.23, p5.003). Specifically, striae scores at the breast and hips were significantly higher among women who had PT. Logistic regression analysis revealed that TSS (OR50.079; 95% CI 1.012, 1.151; p5.021), as well as a rise in body mass index (BMI) during pregnancy (OR51.025; 95% CI 1.001, 1.049; p5.043) are significant predictors of PT. Conclusions: This study demonstrates a significant relation between SG and PT. The findings suggest that SG assessment may be used in the clinical setting by midwives and nurses as a simple and noninvasive tool to better define women at risk for PT.

OBJECTIVE: Pre-pregnancy obesity poses risks to both pregnant women and their infants. This study used a large population-based data source to examine trends, from 1993 through 2003, in the prevalence of pre-pregnancy obesity among women who delivered live infants. METHODS: Data from the Pregnancy Risk Assessment Monitoring System in nine states were analyzed for trends in pre-pregnancy obesity (BMI
29.0 kg/m2) overall and by maternal demographic and behavioral characteristics. Pre-pregnancy BMI was calculated from self-reported weight and height on questionnaires administered after delivery, and demographic characteristics were taken from linked birth certificates. The sample of 66,221 births was weighted to adjust for survey design, non-coverage, and non-response, and it is representative of all women delivering a live birth in each particular state. The sampled births represented 18.5% of all births in the United States. RESULTS: Pre-pregnancy obesity increased 69.3% during the study period, from 13.0% in 1993 to 1994 to 22.0% in 2002 to 2003. The percentage increase ranged from 45% to 105% for individual states. Subgroups of women with the highest prevalence of obesity in 2002 to 2003 were those who were 20 to 29 years of age, black, had three or more children, had a high school education, enrolled in Women, Infants, and Children, or were non-smokers. However, all subgroups of women examined experienced at least a 43% increase in pre-pregnancy obesity over this time period. DISCUSSION: The prevalence of pre-pregnancy obesity is increasing among women in these nine states, and this trend has important implications for all stages of reproductive health care.

Background Excessive weight gain during pregnancy seems to increase birthweight and the off spring’s risk of obesity later in life. However, this association might be confounded by genetic and other shared eff ects. We aimed to examine the association between maternal weight gain and birthweight using state-based birth registry data that allowed us to compare several pregnancies in the same mother. Methods In this population-based cohort study, we used vital statistics natality records to examine all known births in Michigan and New Jersey, USA, between Jan 1, 1989, and Dec 31, 2003. From an initial sample of women with more than one singleton birth in the database, we made the following exclusions: gestation less than 37 weeks or 41 weeks or more; maternal diabetes; birthweight less than 500 g or more than 7000 g; and missing data for pregnancy weight gain. We examined how differences in weight gain that occurred during two or more pregnancies for each woman predicted the birthweight of her off spring, using a within-subject design to reduce confounding to a minimum. Findings Our analysis included 513 501 women and their 1 164 750 off spring. We noted a consistent association between pregnancy weight gain and birthweight (β 7·35, 95% CI 7·10–7·59, p<0·0001). Infants of women who gained more than 24 kg during pregnancy were 148·9 g (141·7–156·0) heavier at birth than were infants of women who gained 8–10 kg. The odds ratio of giving birth to an infant weighing more than 4000 g was 2·26 (2·09–2·44) for women who gained more than 24 kg during pregnancy compared with women who gained 8–10 kg. Interpretation Maternal weight gain during pregnancy increases birthweight independently of genetic factors. In view of the apparent association between birthweight and adult weight, obesity prevention eff orts targeted at women during pregnancy might be benefi cial for off spring.

Objective: To examine the association between obesity subtypes and risk of early and late pre-eclampsia. Design: Population-based retrospective study. Setting: State of Missouri maternally linked birth cohort files. Population: All singleton live births in the state of Missouri from 1989 to 2005. Methods: The body mass index (BMI) was used to classify women as normal weight (BMI = 18.5–24.9 kg/m2), class I obesity (BMI = 30–34.9 kg/m2), class II obesity (BMI = 35–39.9 kg/m2), class III obesity (BMI = 40–49.9 kg/m2) or super-obesity (BMI ‡ 50 kg/m2). Adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between obesity and the risk of pre-eclampsia were obtained from logistic regression models with adjustment for intracluster correlation. Results: The rate of pre-eclampsia increased with increasing BMI, with super-obese women having the highest incidence (13.4%). Compared with normal weight women, obese women (BMI ‡ 30 kg/m2) had a higher risk for pre-eclampsia (OR = 2.59, 95% CI = 2.87–3.01). This risk remained approximately the same for late-onset pre-eclampsia (preeclampsia occurring at 34 weeks or more of gestation) and was slightly reduced for early-onset pre-eclampsia (pre-eclampsia occurring at 34 weeks or less of gestation). Within each BMI category, the risk of pre-eclampsia increased with the rate of weight gain. Compared with normal weight mothers with moderate weight gain, super-obese women with a high rate of weight gain had the greatest risk for pre-eclampsia (OR = 7.52, 95% CI = 2.70–21.0). Conclusion: BMI and rate of weight gain are synergistic risk factors that amplify the burden of pre-eclampsia among super-obese women.

We compared obstetric outcomes based on gestational weight gain in normalweight and obese women using traditional Institute of Medicine (IOM) guidelines and newly recommended Cedergren criteria. Using the New Jersey Pregnancy Risk Assessment Monitoring System (PRAMS) database and electronic birth records, perinatal outcomes were analyzed to estimate the independent effects of prepregnancy body mass index (BMI) and gestational weight gain by IOM versus Cedergren criteria. Of 9125 subjects in PRAMS database from 2002 to 2006, 53.7% had normal BMI, 12.3% were overweight, 18.2% were obese, and the rest were underweight. Among normal-weight mothers, when compared with the IOM guidelines, macrosomia (6.45% versus 4.27%) and cesarean delivery rates (30.42% versus 29.83%) were lower using Cedergren criteria but the rates of preterm delivery (5.06% versus 9.44%), low birth weight (0.38% versus 2.42%), and neonatal intensive care unit (NICU) admissions (7.02% versus 10.86%) were higher with the Cedergren criteria. Similarly, among obese patients, when compared with IOM guidelines, macrosomia (10.79% versus 5.47%) and cesarean delivery rates (43.95% versus 40.71%) were lower using Cedergren criteria but the rates of preterm delivery (6.83% versus 8.32%), low birth weight (0.87% versus 1.88%), and NICU admissions (8.92% versus 13.78%) were higher with the Cedergren criteria. Based on our results, ideal gestational weight gain is presumably somewhere between the IOM and Cedergren’s guidelines.

We assessed the impact of a lifestyle modification program (LMP) on weight gain in pregnancy and evaluated its effect on adverse pregnancy outcomes. A prospective matched controlled study design was employed. Inclusion criteria consisted of pregnant women with singleton gestations and body mass index (BMI) >30 without underlying medical conditions. In the study group, patients were prospectively enrolled in the first trimester. Through the LMP, women participated in a comprehensive program on nutrition, exercise, and weight control in pregnancy. The control group consisted of matched patients by starting BMI, parity, and socioeconomic status during the same study period cared for at the same institution. The primary outcome evaluated was weight gain in pregnancy. Adverse pregnancy outcomes including preeclampsia, gestational diabetes, gestational hypertension, and various postpartum complications were evaluated between the two groups. Statistical analysis was performed using nonparametric methods, with p<0.5 considered significant. Twenty-eight patients were recruited for this study and underwent the intervention. Patient compliance with the LMP was 75%, two patients were lost to follow-up, one had a preterm delivery, and four had incomplete data due to various reasons. Twenty-one patients completed their pregnancy and were available for analysis. Twenty matched control patients were identified for analysis. Study participants gained significantly less weight in their pregnancies when compared with controls (mean weight gain 17 versus 34 pounds, respectively; p¼0.008). Secondary outcomes of preeclampsia, gestational diabetes, cesarean section, as well as infant birth weight did not significantly differ between the groups. This study suggests an effective method of reducing prenatal weight gain in the obese population. This type of comprehensive intervention could be an important, cost-effective risk-reduction strategy.

OBJECTIVE: We sought to determine whether genetic variants associated with diabetes and obesity predict gestational weight gain. STUDY DESIGN: A total of 960 participants in the Pregnancy, Infection, and Nutrition cohorts were genotyped for 27 single-nucleotide polymorphisms (SNPs) associated with diabetes and obesity. RESULTS: Among Caucasian and African American women (n = 960), KCNQ1 risk allele carriage was directly associated with weight gain (P < .01). In Bayesian hierarchical models among Caucasian women (n = 628), we found posterior odds ratios >3 for inclusion of TCF2 and THADA SNPs in our models. Among African American women (n = 332), we found associations between risk allele carriage and weight gain for the THADA and INSIG2 SNPs. In Bayesian variable selection models, we found an interaction between the TSPAN8 risk allele and pregravid obesity, with lower weight gain among obese risk allele carriers. CONCLUSION: We found evidence that diabetes and obesity risk alleles interact with maternal pregravid body mass index to predict gestational weight gain.