Endometrial stromal sarcoma: analysis of recurrence following adjuvant treatment.

OBJECTIVE: Endometrial stromal sarcoma (ESS) is a rare and indolent form of uterine cancer with ill-defined post-operative treatment guidelines. The goal of this study was to evaluate the rate of recurrence and the effect of various adjuvant treatment modalities. METHODS: Patients with ESS at 4 institutions were identified (1986-2007). Patient demographics, pathology, treatment, and follow-up information were collected. Chi-square statistical analysis was performed. RESULTS: Forty-three patients with ESS were identified. All patients initially underwent hysterectomy. Twenty-eight (66.7%) had early stage, 12 (28.6%) had advanced stage ESS, and 2 (4.8%) had no staging information. Eight patients received pelvic and or vaginal cuff radiation treatment, with or without chemotherapy. Sixteen of 43 patients experienced a recurrence at an average of 100.5months. Thirty-three patients were treated with progestin therapy alone or followed expectantly. Complete outpatient records were available for 28 of these patients. Sixteen patients (57%) were followed expectantly while 12 (43%) received progestins. Patients receiving progestins vs. expectant management had a lower rate of recurrence in stage 1 (14.3% vs 38.5%, p=0.26) and all stages (33% vs 50%, p=0.38). Twenty-three of 28 (82.1%) patients underwent initial oophorectomy. Eight of 23 (34.8%) had a recurrence, compared to 4 of 5 (80%) in those who retained their ovaries (p=0.06). CONCLUSIONS: ESS is a rare cancer that is difficult to study. We found removal of the adnexa and post-operative treatment with progestin therapy decreased recurrence rates. These two treatment strategies should be considered in the treatment of patients with all stages of ESS.

Intrapartum considerations in prenatal care.

The epidemic of obesity continues to grow undaunted, promising to affect the lives of more women of childbearing age. The challenges facing those charged with obstetrical care of the obese may require variation in care from forethought and planning, to consultation or referral for care at specialized centers. The routine management of late pregnancy must take into account the increase in risk for late fetal loss, failed induction and trial of labor after cesarean delivery, and postcesarean complications, such as wound-related morbidity and venous thromboembolism. Awareness of prolonged labor curves and the risk of shoulder dystocia must also be part of the management of labor. The data regarding many interventions attempted on behalf of these at risk gravidas are rudimentary but may allow for modifications in care that will positively impact outcomes for mother and child.

The impact of maternal obesity on satisfactory detailed anatomic ultrasound image acquisition.

OBJECTIVE: To assess the impact of maternal body mass index (BMI) on ultrasound visualisation of fetal morphology. STUDY DESIGN: Singleton pregnancies undergoing targeted ultrasound fetal anatomic evaluation at 18- to 25-weeks gestation from 1/05 to 12/05 were included. Ultrasound reports and maternal medical records were reviewed for maternal characteristics and documentation of adequatecy of ultrasound visualisation for each organ system was obtained by individual chart review. BMI was divided into normal (18.5-24.9 kg/m2) and obese (>30 kg/m2) groups. Overweight women (BMI 25-29.9 kg/m2) were excluded. Suboptimal visualisation for each organ system was compared between BMI groups. Multivariable analysis controlled for sonographer, physician, US equipment, race, parity, fetal lie, weight and gestational age. RESULTS: Eight hundred fourteen patients were included (Normal = 148, Obese = 666). The frequency of suboptimal visualisation was significantly increased in the obese group for the cardiovascular system SV (50.9% vs. 26.9%, p < 0.0001), facial soft tissue SV (39.1% vs. 19.3%p < 0.0001) and abdominal wall SV (2.7% vs. 0%, p < 0.0001). Suboptimal visualisation declined with advancing gestational age. CONCLUSIONS: Suboptimal fetal anatomic visualisation is increased with maternal obesity, but declines with advancing gestational age in both normal weight and obese populations.

Maternal obesity, uterine activity, and the risk of spontaneous preterm birth.

OBJECTIVE: To assess the associations among maternal obesity, uterine contraction frequency, and spontaneous preterm birth in women at risk for spontaneous preterm birth. METHODS: In a secondary analysis, we analyzed data from 253 women at risk for spontaneous preterm birth (prior spontaneous preterm birth, vaginal bleeding) enrolled in a multicenter observational study of home uterine activity monitoring at 11 centers. All women wore a uterine activity monitor twice daily from 22 weeks through 34 weeks of gestation. Mean and maximal contractions/hour at 22-24, 25-26, 27-28, 29-30, 31-32 weeks, and at or after 33 weeks of gestation were compared between overweight/obese women (a body mass index [BMI] at 22-24 weeks greater than 25 kg/m) and normal/underweight women (a BMI of 25 kg/m or less) at each gestational age interval. Multivariable analysis evaluated the influences of BMI, contractions, fetal fibronectin, and transvaginal cervical length on spontaneous preterm birth before 35 weeks. RESULTS: Obese/overweight women (n=156) were significantly less likely to experience spontaneous preterm birth before 35 weeks (8.3% compared with 21.7%, P<.01). For each gestational age interval before 32 weeks, obese/overweight women had fewer mean contractions/hour (P<.01 for each) and maximal contractions/hour (P<.01 for each) than normal/underweight women, although their mean cervical lengths (34.3 mm compared with 33.1 mm, P=.25), and fetal fibronectin levels (7.1% compared with 7.2% 50 ng/mL or more, P=.97) were similar at study enrollment. Obese/overweight status was associated with a lower risk of spontaneous preterm birth before 35 weeks after controlling for contraction frequency and other factors evaluated at 22-24 weeks, but not at later periods. CONCLUSION: Obese/overweight women at risk for spontaneous preterm birth exhibit less uterine activity and less frequent spontaneous preterm birth before 35 weeks of gestation than normal/underweight women. LEVEL OF EVIDENCE: II.

Abbreviated postpartum magnesium sulfate therapy for women with mild preeclampsia: a randomized controlled trial.

OBJECTIVE: To determine whether women receiving 12-hour and 24-hour postpartum magnesium sulfate (MgSO4) therapy for mild preeclampsia have differing clinical courses. METHODS: Consenting women with suspected mild preeclampsia were randomly assigned to 12 hours or 24 hours of MgSO4 postpartum therapy. Treatment was continued after the assigned time period if there was evidence of severe preeclampsia. The frequency of progression to severe disease and other outcomes were compared between study groups using the Fisher exact, chi2, and Student t tests where appropriate. RESULTS: Between January 2001 and August 2004, 200 women were enrolled. The 12-hour and 24-hour groups were similar in age, parity, delivered gestational age, anesthesia, and mode of delivery, as well as for proteinuria and blood pressure. In the 12-hour group, MgSO4 treatment was extended in seven women (6.9%) for progression to severe disease versus one (1.1%) in the 24-hour group (P = .07). Women who developed severe disease had higher blood pressures at the first prenatal visit (140/78 versus 122/69, P < or = .02 for systolic and diastolic pressures), at the time of randomization (152/88 versus 135/78, P < or = .03 for systolic and diastolic pressures), and were more likely to have insulin-requiring diabetes (27.3% versus 4.4%, P = .03). No 12-hour patients required treatment beyond 24 hours postpartum. There were no seizures, MgSO4 toxicity, or intolerance in either group. CONCLUSION: Twelve hours of postpartum MgSO4 therapy for mild preeclampsia is associated with infrequent disease progression and a clinical course similar to that with 24-hour therapy. Patients with chronic hypertension and insulin-requiring diabetes are at risk for progression to severe disease postpartum. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00344058 LEVEL OF EVIDENCE: I.

Perinatal intervention and neonatal outcomes near the limit of viability.

OBJECTIVE: The purpose of this study was to evaluate trends in the level of obstetric and neonatal intervention near the limit of viability and perinatal morbidity and mortality rates over time. STUDY DESIGN: In this retrospective chart review, live-born infants who were delivered at 23 to 26 weeks of gestation and who weighed between 500 and 1500 g between 1990 and 2001 in an urban tertiary care center were identified. Maternal charts were reviewed for clinical characteristics and antenatal and intrapartum course. Neonatal charts were reviewed for short-term morbidities that included respiratory distress syndrome, intraventricular hemorrhage, necrotizing enterocolitis, retinopathy of prematurity, and survival. The study group was divided into 2 cohorts (group I:1990-95; group II:1996-2001); the obstetrician's willingness to intervene, neonatal resuscitation efforts, infant mortality (in gestational age subgroups) rate, and short-term morbidity rate were compared. Multivariate analyses, which controlled for obstetrician willingness to intervene, neonatal resuscitation, cohort, and gestational age, were performed to evaluate infant survival in the entire cohort and for morbidity in the survivors. RESULTS: Records for 260 mothers and 293 newborn infants were evaluated. Comparing the 2 cohorts (group I vs II), we found increases over time in intent to intervene for fetal indication (70% vs 89%; P = .0007), cesarean delivery for malpresentation (20% vs 42%; P = .0003), and survival (54% vs 70%; P = .003). Pregnancies in group 1 were less likely to have received antenatal steroids (7.7% vs 60%) or surfactant (39% vs 73%; P <.0001 for each). Survival increased with advancing delivery gestation (24%, 51%, 68%, and 85% at 23, 24, 25, and 26 weeks of gestation, respectively; P <.0001). However, among survivors, the incidences of necrotizing enterocolitis, retinopathy of prematurity, intraventricular hemorrhage, respiratory distress syndrome, sepsis, and bronchopulmonary dysplasia did not decline significantly with advancing gestational age, after controlling for other factors. CONCLUSION: Obstetric intervention and aggressive neonatal resuscitation have increased for pregnancies delivered between 23 and 26 weeks of gestation over the past decade. Although survival has increased over time and with advancing gestational age at delivery, short-term morbidity in survivors is similar, regardless of gestational age in this cohort. A brief delay in delivery of those pregnancies who are at risk for delivery between 23 and 26 weeks of gestation may improve survival, although short-term morbidity in survivors will not be affected substantially.

The impact of maternal obesity and weight gain on vaginal birth after cesarean section success.

OBJECTIVE: This study was undertaken to determine the impact of maternal obesity on success of a trial of labor (vaginal birth after cesarean section [VBAC]) after a single low transverse cesarean delivery. STUDY DESIGN: Individual charts of women with low transverse cesarean delivery in their first viable pregnancy who underwent a VBAC in their second viable pregnancy at our urban tertiary care institution were reviewed. Maternal body mass index (BMI) was classified as underweight (<19.8 kg/m2), normal (19.8-24.9 kg/m2), overweight (25-29.9 kg/m2), or obese (> or =30 kg/m2). Clinical characteristics and labor outcomes were assessed. Factors potentially affecting VBAC success were analyzed by univariate analysis. Logistic regressions were performed to determine the impact of maternal pregravid BMI on VBAC success after controlling for confounding factors. RESULTS: Of 510 women attempting a trial of labor, 337 (66%) were successful and 173 (34%) failed VBAC. Decreased VBAC success was seen in obese (54.6%) but not overweight (65.5%) women compared with women of normal BMI (70.5%), P = .003 and .36, respectively. Underweight women had more VBAC success than women of normal BMI (84.7% vs 70.5%, P = .04). Controlling for other factors, the association between increasing pregravid BMI and BMI > or =30 kg/m 2 with decreased VBAC success persisted, P = .03 and .006, respectively. Normal BMI women who became overweight before the second pregnancy had decreased VBAC success compared with those whose BMI remained normal (56.6% vs 74.2%, P = .006). However, overweight women who decreased their BMI to normal before the second pregnancy did not significantly improve VBAC success (64.0% vs 58.4%, P = .67). CONCLUSION: Increasing pregravid BMI and weight gain between pregnancies reduce VBAC success after a single low transverse cesarean delivery.

The influence of obesity and diabetes on the prevalence of macrosomia.

OBJECTIVE: This study was undertaken to determine the relative contribution of abnormal pregravid maternal body habitus and diabetes on the prevalence of large-for-gestational-age infants. STUDY DESIGN: Maternal and neonatal records for singleton term (> or =37 weeks' estimated gestational age) deliveries January 1997 through June 2001 were reviewed. Subjects were characterized by pregravid body mass index (BMI), divided into underweight (BMI <19.8 kg/m2), normal (BMI 19.8-25 kg/m2), overweight (BMI 25.1-30 kg/m2), and obese (BMI >30 kg/m2) subgroups. Diabetes was classified as gestational, treated with diet alone (A1GDM), or with insulin (A2GDM), and pregestaional diabetes (PDM). Newborn weight greater than the 90th percentile for gestational age, based on published local birth weight data, defined large for gestational age (LGA). The risk of LGA delivery for underweight, overweight, and obese women were compared with that of women with normal pregravid BMI. Multiple regression models, including parity, newborn sex, BMI, race, and diabetes, were constructed to examine the relative effect of abnormal BMI and diabetes on the risk of the delivery of an LGA infant. RESULTS: Complete data for 12,950 deliveries were included (1,640 [13.0%] underweight, 2,991 [23.7%] overweight, and 2,928 [23.2%] obese). LGA delivery affected 11.8% of the study sample; 303 (2.3%) of subjects had A1GDM, whereas 94 (0.7%) had A2GDM, and 133 (1.6%) had PDM. Compared with normal BMI subjects, obese women were at elevated risk for LGA delivery (16.8% vs 10.5%; P < .0001) as were overweight women (12.3% vs 10.5%; P = .01). Diabetes was also a risk factor for LGA delivery (A1GDM: [29.4% vs 11.4%]; A2GDM: [29.8% vs 11.7%]; PDM: [38.3% vs 11.6%]; P < .0001 for each). Other risk factors for LGA delivery included parity (13.2% vs 9.5%; P < .0001), and male gender (14.3% vs 9.3%; P < .0001). Black race and low pregravid BMI were associated with a lower risk of LGA delivery (9.0% vs 13.7%; P < .0001) and (6.4% vs 10.5%; P = .006), respectively. Multiple regression revealed the independent influence of pregravid obesity and PDM, increasing the risk of LGA delivery (BMI >30kg/m 2 [Adjusted odds ratio (AOR) = 1.6]), and PDM (AOR = 4.4). CONCLUSION: Obesity and pregestational diabetes are independently associated an increased risk of LGA delivery. The impact of abnormal body habitus on birth weight grows as BMI increases. Diabetes has the greatest affect on the normal and underweight population. With the increasing prevalence and relative frequency of overweight and obese women in pregnancy compared with diabetes (46.7% vs 4.1%), abnormal maternal body habitus exhibits the strongest influence on the prevalence of LGA delivery in our population.

The influence of obesity and diabetes on the risk of cesarean delivery.

OBJECTIVE: To determine the influence of pregravid obesity and diabetes on cesarean delivery (CD) risk. STUDY DESIGN: Women with singleton pregnancies of 23 weeks or more estimated gestational age who were undergoing a trial of labor January 1997 through June 2001 were categorized by pregravid body mass index (underweight [<19.8 kg/m 2 ], normal [19.8-25 kg/m 2 ], overweight [25.1-30 kg/m2], obese [>30 kg/m2]). Diabetes (DM) was divided into categories of gestational, treated with diet modification (A1GDM) or insulin (A2GDM), and pregestational (PDM). Prior CDs were excluded. CD rates for each group were compared in univariate analyses stratified by estimated gestational age (term, preterm, total). Other variables examined included DM, macrosomia (birth weight 4500 g or more), induction, and parity. Multiple regression included significant variables to predict the influence of diabetes and obesity on CD risk. RESULTS: Records for 12,303 deliveries were evaluated (obese: 2828 [22.9%]; overweight: 2605 [21.2%]; A1GDM: 270 [2.2%]; A2GDM: 93 [0.8%]; PDM: 126 [1%]). Obese and overweight subjects had a higher risk for CD, compared with normal subjects (13.8% and 10.4% versus 7.7%, P < .0001 for each). Other CD risk factors were macrosomia (25% versus 9.4%), nulliparity (16.5% versus 4.7%), induction (17.4% versus 8.3%), diabetes (A1GDM: 16.7% versus 9.4%; A2GDM: 24.7% versus 9.5%; PDM: 34.9% versus 9.3%) and black race (10.7% versus 8.8%) ( P < .0001 for each). In multiple regression models including term deliveries, obesity and PDM were independent CD risk factors ([adjusted OR overweight: 1.5, P < .0001; adjusted OR PDM: 2.9, P = .01]; [adjusted OR obese: 2.4, P < .0001, PDM: 2.9, P = .0002]). CONCLUSION: Pregravid obesity and diabetes independently increase the risk for CD. Given the disparate prevalence of obesity and diabetes in the United States, body habitus has a significantly larger impact on CD risk.

The influence of obesity and gestational diabetes mellitus on accretion and the distribution of adipose tissue in pregnancy.

OBJECTIVE: The purpose of this study was to evaluate the effect of pregravid obesity and gestational diabetes mellitus (GDM) on the longitudinal accretion and distribution of adipose tissue in pregnancy. STUDY DESIGN: Women with normal glucose tolerance and GDM were evaluated before conception, early (12-14 weeks) and late (33-36 weeks) in gestation. Fat mass, lean body mass, and percent body fat were assessed longitudinally with hydrodensitometry. Serial biceps, triceps, subscapular, iliac, costal, mid thigh, and lower thigh skinfold measurements quantified the changes in fat mass distribution. Pregravid obesity was defined as >25% body fat. RESULTS: Subjects included 19 patients with GDM (5 lean women, 14 obese women), and 33 patients with normal glucose tolerance (controls; 12 lean women, 21 obese women). GDM and control subjects were similar in pregravid percent body fat (29.6% vs 27.9%, P=.47) and fat mass (20.8 kg vs 18.2 kg, P=.37). Values for subjects with GDM and controls were also similar in terms of percent body fat, fat mass, and weight gained (change in percent body fat, -0.7% vs 1.9% [P=.07]; change in fat mass, 3.8 kg vs 5.0 kg [P=.08]; change in weight, 12.0 kg vs 13.2 kg [P=.35]). Lean subjects gained more percent body fat compared with obese subjects (change in percent body fat, 3.3% vs 0.1% [P=.004]) but gained similar amounts of fat mass (change in fat mass, 4.7 kg vs 4.2 kg [P=.58]), lean body mass (7.6 kg vs 8.8 kg [P=.18]), and weight (change in weight, 12.3kg vs 13.0 kg [P=.61]) The distribution of adipose tissue that was accumulated as estimated with skinfold measurements was similar between patients with GDM and glucose tolerance (P>.05 for all changes in skinfolds), but significantly different between lean and obese patients (P<.05 for all changes in skinfolds). Lean women gained a predominance of adipose tissue peripherally over that in obese women. CONCLUSION: Lean women accrue significantly more fat mass than obese women, regardless of glucose tolerance. Pregestational obesity rather than GDM influences the distribution of adipose accretion.

Pregnancy in a spinal cord-injured bilateral total leg amputee: management and considerations.

A 35-year-old woman, gravida 2, para 0, was seen at 20 weeks' gestation with complete T10 spinal cord transection at age 15 years, subsequent bilateral total leg amputation, urinary diversion, colostomy, and lumbar spine resection. Pregnancy complications included recurrent urinary tract infections, preterm contractions without cervical change, lumbosacral abscesses, and fetal malpresentation. Delivery was through cesarean section near term.

Low maternal weight, failure to thrive in pregnancy, and adverse pregnancy outcomes.

OBJECTIVE: The purpose of this study was to correlate low maternal pregravid weight, delivery weight, and poor gestational weight gain with perinatal outcomes. STUDY DESIGN: Maternal and perinatal data from January 1997 to June 2001 were obtained from a perinatal database at MetroHealth Medical Center. Low maternal weight (LMW) was defined as pregravid or delivery weight <100 pounds or body mass index (BMI) < or =19.8 kg/m(2). Low maternal weight gain was defined as <0.27 kg per week. Perinatal complication rates in these subjects were compared with those with weights of 100 to 200 pounds, normal BMI (>19.8, <26 kg/m(2)), and normal gestational weight gain (0.27-0.52 kg/wk). Chi-square and t tests were used where appropriate. P<.05 was significant. RESULTS: A percentage (2.6%) of 15,196 subjects began pregnancy weighing < or =100 pounds; 0.15% weighed <100 pounds at delivery and 13.2% had a pregravid BMI < or =19.8 kg/m(2). Pregravid LMW was highly correlated with ethnicity (Asians, 8.6%; Hispanics, 4.3%; Caucasians, 2.5%; African Americans, 1.9%; P<.001). Subjects with pregravid LMW were at increased risk for intrauterine growth restriction (IUGR) (relative risk [RR], 2.3, 95% CI, 1.3-4.05), and perineal tears (3rd-degree lacerations; RR, 1.8, 95% CI, 1.1-2.9), and low birth weight ([LBW] <2500 g; RR, 1.8, 95% CI, 1.1-2.9). They had a lower risk of cesarean section (RR, 0.72, 95% CI, 0.56-0.92) and preterm delivery (PTD) (RR, 1.1, 95% CI, 0.97-1.06). Pregravid BMI <19.8 kg/m(2) was associated with preterm labor (PTL) (RR, 1.22, 95% CI, 1.02-1.46), IUGR (RR, 1.67, 95% CI, 1.2-2.39), and LBW (<2500 g; RR, 1.13, 95% CI, 1.0-1.27) and was protective against cesarean delivery (RR, 0.8, 95% CI, 0.71-0.91). Delivery LMW was associated with LBW (<2500 g; RR, 2.81, 95% CI, 1.62-4.84), active-phase arrest (RR, 5.07, 95% CI, 1.85-13.9), PTL and PTD (RR, 2.5, 95% CI, 1.02-6.33, and RR, 2.45, 95% CI, 1.4-4.4, respectively), a lower gestational age at delivery (36.8 vs 38.3 wks, P<.05), and mediolateral episiotomy (RR, 9.6, 95% CI, 1.9-48.0). A percentage (0.8%) of subjects had BMI <19.8 kg/m(2) at delivery. Low delivery BMI was associated with birth weight <2500 g (RR, 1.74, 95% CI, 1.3-2.32), PTL (RR, 2.16, 95% CI, 1.45-3.19), and PTD (RR, 1.57, 95% CI, 1.18-2.11). Failure to thrive in pregnancy (weight gain <0.27 kg/wk) was associated with LBW (<1500 g; RR, 1.23, 95% CI, 1.03-1.45), <2500 g; RR, 1.22, 95% CI, 1.13-1.33), and PTL and PTD (RR, 1.2, 95% CI, 1.05-1.37, and RR, 1.11, 95% CI, 1.02-1.2, respectively). CONCLUSION: Low weight and BMI at conception or delivery, as well as poor weight gain during pregnancy, are associated with LBW, prematurity, and maternal delivery complications.

Prevalence of maternal obesity in an urban center.

OBJECTIVE: The purpose of this study was to evaluate the changing prevalence of maternal obesity in an urban center. STUDY DESIGN: The prevalence of obesity in 31,542 pregnancies from January 1986 to December 1996 (group 1) was compared with the prevalence of obesity in 15,600 pregnancies between January 1997 and June 2001 (group 2). Maternal weight was divided into two groups according to measurements performed at delivery (200 pounds). Women who weighed >or=200 pounds were divided into subgroups for analysis (201-250 pounds, 251-300 pounds, and >300 pounds). The incidence of obesity by weight group was evaluated for a change over time; the impact of race and socioeconomic status was analyzed. A probability value of <.05 was considered significant. RESULTS: Maternal obesity was significantly more common in group 2 (>200 pounds: 28% vs 21%; relative risk, 1.3; 95% CI, 1.3-1.4; 201-250 pounds: 20% vs 16%; relative risk, 1.3; 95% CI, 1.2-1.3; 251-300 pounds: 5.5% vs 3.7%; relative risk, 1.5; 95% CI, 1.3-1.6; >300 pounds: 1.6% vs 1.2%; relative risk, 1.4; 95% CI,1.2-1.7; P <.001 for each). Obesity was most common in African American women (>200 pounds, 28.1%; 201-250 pounds, 20.5%; 251-300 pounds, 5.5%; and >300 pounds, 2.1 %). The prevalence of obesity increased most among African American women (>200 pounds: 35 % vs 25%; relative risk, 1.4; 95% CI, 1.4-1.5; 201-250 pounds: 25 % vs 18%; relative risk, 1.4; 95% CI, 1.3-1.5; 251-300 pounds: 7.3 % vs 4.6%; relative risk, 1.6; 95% CI, 1.4-1.6; >300 pounds: 2.7% vs 1.8%; relative risk, 1.5; 95% CI, 1.3-1.9; P <.001 for each), and it decreased in Asian women (>200 pounds: 6.8% vs 11%; relative risk, 0.6; 95% CI, 0.4-0.9; P <.05; 201-250 pounds: 6.3% vs 9.7%; relative risk, 0.6; 95% CI, 0.4 -1.1; P >.05; 251-300 pounds: 0.6% vs 1%; relative risk, 0.6; 95% CI, 0.1- 2.9; P >.05; >300 pounds: 0.0% vs 0.3%). The increase in weight over time remained statistically significant after being controlled in multivariate analysis for socioeconomic status and race. Women with milder obesity (201-250 pounds prepregnancy weight) were at increased risk for preeclampsia, gestational and insulin-dependent diabetes mellitus, advanced gestational age (>or=42 weeks), fetal macrosomia, and cesarean delivery (P <.001 for each), with increasing weight being associated with higher risk. CONCLUSION: Obesity that complicates pregnancy has increased significantly over the past 15 years. The risk of perinatal complications increases with increasing maternal pregravid weight; even those women with moderate obesity are at increased risk of adverse outcomes.