Obesity and adverse pregnancy outcomes in twin pregnancies

Abstract

Objective: To compare pregnancy outcomes in twin pregnancies based on maternal pre-pregnancy body mass index (BMI).

Methods: Historical cohort study of all twin pregnancies >24 weeks managed by one maternal-fetal medicine practice from 2005 to 2012. We compared pregnancy outcomes between pre-pregnancy obese (BMI ≥30?kg/m²) and normal weight women (BMI 18.5–24.99?kg/m²). We also compared pre-pregnancy normal weight women to overweight women (BMI 25–29.99?kg/m²) and underweight women (BMI <18.5?kg/m²). Chi square, Fisher’s exact test, Student’s t-test, and one-way ANOVA were used as appropriate. A p value of <0.05 was considered significant.

Results: Five hundred fourteen patients with twin pregnancies were included. Pre-pregnancy obesity was associated with gestational hypertension (34.1% versus 17.9%, p?=?0.011), preeclampsia (27.3% versus 14.4%, p?=?0.028), and gestational diabetes (22.2% versus 4.7%, p?<?0.001). Pre-pregnancy overweight was associated with gestational diabetes (13.7% versus 4.7%, p?=?0.002). Pre-pregnancy underweight was not associated with any adverse pregnancy outcomes. Comparing outcomes across normal weight, overweight, and obese women, the rates of gestational diabetes and gestational hypertension increased significantly across the three groups.

Conclusion: In patients with twin pregnancy, pre-pregnancy obesity is associated with adverse pregnancy outcomes, including gestational diabetes, gestational hypertension, and preeclampsia.     

Risk of adverse pregnancy outcomes stratified for pre-pregnancy body mass index

Objective: To estimate the risk of adverse maternal and perinatal outcomes in women with different pre-pregnancy body mass index (BMI).

Methods: We conducted a cohort study with 14?451 singleton pregnancies in 15 medical centers in Beijing between 20 June 2013 and 30 November 2013 using cluster random sampling. We divided participants into four groups based on pre-pregnancy BMI: Group A (underweight): BMI?<?18.5?kg/m², Group B (normal): 18.5–23.9?kg/m², Group C (overweight): 24–27.9?kg/m², Group D (obesity): ≥28?kg/m². We used multivariate analysis to evaluate the association of the risk of adverse pregnancy outcomes and pre-pregnancy BMI.

Results: The prevalence of maternal overweight and obesity was 14.82% (2142/14?451) and 4.71% (680/14?451) in the study population, respectively. Higher pre-pregnancy BMI is associated with higher prevalence of gestational diabetes (GDM), macrosomia, Cesarean section (C-section), preeclampsia and postpartum hemorrhage. Pre-pregnancy overweight or obesity increases the risk of adverse pregnancy outcomes, regardless of GDM status.

Conclusions: Pre-pregnancy overweight or obesity is associated with increased risk of adverse pregnancy outcomes. Nutrition counseling is recommended before pregnancy in women who have overweight or obesity.     

The effect of prepregnancy body mass index on birth weight,preterm birth,cesarean section,and preeclampsia in pregnant women

Objective: The objective of this study is to determine the impact of maternal prepregnancy BMI on birth weight, preterm birth, cesarean section, and preeclampsia among pregnant women delivering singleton life birth.

Methods: A cross-sectional study of 4397 women who gave singleton birth in Tehran, Iran from 6 to 21 July 2015, was conducted. Women were categorized into four groups: underweight (BMI?2), normal (BMI 18.5–25?kg/m²), overweight (BMI 25–30?kg/m²) and obese (BMI >30?kg/m²), and their obstetric and infant outcomes were analyzed using both univariate and multivariate logistic regression.

Results: Prepregnancy BMI of women classified 198 women as underweight (4.5%), 2293 normal (52.1%), 1434 overweight (32.6%), and 472 as obese (10.7%). In comparison with women of normal weight, women who were overweight or obese were at increased risk of preeclampsia (odds ratio (OR)?=?1.47, 95% CI?=?1.06–2.02; OR?=?3.67, 95% CI?=?2.57–5.24, respectively) and cesarean section (OR?=?1.21, 95% CI?=?1.04–1.41; OR?=?1.35, 95% CI?=?1.06–1.72, respectively). Infants of obese women were more likely to be macrosomic (OR?=?2.43, 95% CI?=?1.55–3.82).

Conclusion: Prepregnancy obesity is a risk factor for macrosomia, preeclampsia, and cesarean section and need for resuscitation.     

Weight gain in gestational diabetes: the effect of treatment modality

Objective: To evaluate treatment effectiveness (diet alone, insulin or glyburide) on maternal weight gain in gestational diabetes (GDM).

Methods: GDM patients were treated with diet alone, insulin or glyburide. Weight gain was stratified into: prior to GDM diagnosis, from diagnosis to delivery and total pregnancy weight gain. Good glycemic control was defined as mean blood glucose ≤105?mg/dl and obesity as Body Mass Index (BMI)?≥?30?kg/m², overweight BMI 25–29?kg/m² and normal <?25?kg/m².

Results: Total weight gain was similar in all the treatment groups. Two-thirds of weight gain occurred prior to diagnosis (diet 85%, insulin 67% and glyburide 78%). Post-diagnosis, patients on diet alone gained less weight than those on insulin or glyburide (p?<?0.001); insulin-treated patients showed greater weight gain than glyburide-treated patients (p?<?0.001). Patients on diet with good glycemic control showed less weight gain after diagnosis than patients on insulin or glyburide (2.8?±?13, 6.6?±?10, 5.2?±?7.9 lbs, respectively, p?<?0.02). Poorly-controlled patients, regardless of treatment, had similar patterns of weight gain throughout pregnancy.

Conclusion: Patterns of maternal weight gain in GDM pregnancies are associated with treatment modality and level of glycemic control.     

The association between maternal pre-pregnancy body mass index and pregnancy outcomes of preeclampsia

ObjectiveTo evaluate the effects of pre-pregnancy maternal body mass index (BMI) to pregnancy outcomes in patients diagnosed as preeclampsia.Materials and methodsThis was a retrospectively study on women who had been diagnosed as preeclampsia and delivered at Seoul National University Bundang Hospital between June 2017 and March 2020. Multifetal gestation, major fetal anomaly, and fetal death in utero were excluded. A total of 150 singleton pregnancies were included and divided into four groups according to the pre-pregnancy BMI classification: underweight (<18.5 kg/m², n = 6), normal (18.5–22.9 kg/m², n = 66), overweight (23.0–24.9 kg/m², n = 26), and obese (≥25.0 kg/m², n = 52). Pregnancy outcomes including gestational age at delivery, birthweight, and delivery modes were reviewed.ResultsThe rates of preterm birth before 34 weeks of gestation were 67%, 49%, 35%, and 27% for underweight group, normal BMI group, overweight group, and obese group, respectively (p-trend = 0.006). The birthweight of newborn increased significantly as pre-pregnancy BMI increased (p-trend<0.001). The proportions of small for gestational age (SGA) were highest in underweight group and decreased as pre-pregnancy BMI increased (67%, 41%, 42%, and 10% for each group, respectively, p-trend<0.001).ConclusionThe rates of preterm birth before 34 weeks and SGA increased as pre-pregnancy BMI decreased in patients with preeclampsia.Implications for practiceWomen with underweight before pregnancy are at the highest risk for preterm birth and SGA, therefore they need to be monitored more intensively when diagnosed as preeclampsia.     

Triplet gestation outcomes in relation to maternal prepregnancy body mass index and weight gain

Objective.?To study prepregnancy maternal body mass index (BMI) and overall maternal weight gain in triplet gestations in relation to maternal and newborn outcomes.

Study design.?This was a retrospective study of birth certificate data of all live-born triplet gestations occurring between 1999 and 2003 in an eight-county region in New York. An analysis of computerized birth certificate data for variables related to pregnancy and newborn outcomes was conducted, looking at neonatal birth weight, neonatal gestational age, and the occurrence of the maternal pregnancy complications of gestational diabetes, gestational hypertension, and preeclampsia.

Results.?In 56 triplet gestations studied, the prepregnancy BMI was not associated with mean newborn birth weights and gestational age at delivery. The total maternal weight gain was associated with increasing mean birth weight and higher gestational age at delivery. Pregnancy complications in triplet pregnancies of gestational diabetes and gestational hypertension were associated with prepregnancy BMI, but not maternal weight gain.

Conclusion.?For triplet gestations, a normal prepregnancy BMI and a total gestational weight gain of at least 15.9 – 20.5 kg (35 – 45 lb) are associated with fewer pregnancy complications.     

McDonald versus Shirodkar cervical cerclage for the prevention of preterm birth: impact of body mass index

Objective: To compare obstetrical outcomes on women undergoing a McDonald or Shirodkar cerclage and to estimate the impact of maternal body mass index (BMI) on these outcomes.

Methods: We conducted a retrospective review of the medical records of all women with singleton pregnancies who underwent placement of a McDonald or Shirodkar cerclage at St. Francis Hospital from January 2008 to October 2013. The subjects were categorized based on BMI groups (normal: less than 25?kg/m², overweight: 25–29?kg/m², obese: 30?kg/m² or more). The primary outcome was gestational age at delivery. Statistical analyses included chi-square, Student’s t-test, and multivariable regression analysis.

Results: Of 95 women, 47 (49.5%) received a Shirodkar, and 48 (50.5%) a McDonald cerclage. 16 women (16.8%) were categorized as normal weight, 35 (36.8%) as overweight, and 44 (46.3%) as obese. Gestational age at delivery differed significantly by group, decreasing with each categorical increase in BMI (normal: 39.0?±?0.3 weeks; overweight: 36.6?±?0.7 weeks; obese: 33.0?±?1.1 weeks; p?p?=?.02). However, analysis showed a significant interaction between weight status and gestational age at delivery. Obese women had significantly longer pregnancies when they received a Shirodkar cerclage versus a McDonald cerclage (32.6?±?1.0 weeks versus 28.8?±?0.9 weeks; p?p?=?.63).

Conclusions: Compared to obese women receiving a McDonald cerclage, obese women receiving a Shirodkar cerclage had significantly longer pregnancies. No significant differences in pregnancy duration were found in normal/overweight women regardless of cerclage technique. Pregnancy duration in obese women receiving a Shirodkar cerclage was similar to the pregnancy duration of normal/overweight women.     

Rates of recurrent preterm birth by maternal body habitus in women receiving 17α-hydroxyprogesterone caproate

Abstract

Objective: To examine the influence of maternal pre-pregnancy body mass index (BMI) on the rates of recurrent spontaneous preterm birth (SPTB) in women receiving 17α-hydroxyprogesterone caproate (17P).

Methods: Retrospective analysis of a cohort of 6253 women with a singleton gestation and prior SPTB enrolled in 17P home administration program between 16.0 and 26.9 weeks. Data were grouped by pre-pregnancy BMI (lean <18.5?kg/m², normal 18.5–24.9?kg/m², overweight 25–29.9?kg/m² and obese ≥30.0?kg/m²). Delivery outcomes were compared using χ² and Kruskal–Wallis tests with statistical significance set at p?<?0.05.

Results: SPTB<28 weeks was significantly lower in normal weight women. Rates of recurrent SPTB<37 weeks were highest in the group with BMI<18.5?kg/m². Lean gravidas were younger, more likely to smoke, and less likely to be African–American than those with normal or increased BMI. In logistic regression, after controlling for race and prior preterm birth <28 weeks, the risk of SPTB<37 weeks decreased 2% for every additional 1?kg/m² increase in BMI.

Conclusions: Recurrent spontaneous preterm delivery<37 weeks in patients on 17P is more common in lean women (BMI<18.5?kg/m²), and less common in obese women (BMI ≥30?kg/m²) suggesting that the current recommended dosing of 17?P is adequate for women with higher BMI.     

Excessive weight gain and hypertensive disorders of pregnancy in the obese patient

Objective: To evaluate the association between excessive weight gain and pregnancy-related hypertension (PRH) among obese women (body mass index (BMI) ≥30?kg/m²).

Methods: We performed a case control study among women with (n?=?440) and without (n?=?600) PRH from 2005 to 2007. Height and weight were recorded at initial and final prenatal visits. 695 women had BMI recorded at ≤18 weeks of gestation, of which 257 (36.9%) were obese. Obese women were divided into three categories based on 2009 Institute of Medicine (IOM) guidelines: (1) below recommended amount (under weight gain – UWG); (2) more than recommended (excessive weight gain – EWG) or (3) within recommended amount (normal weight gain – NWG). PRH was defined as gestational hypertension, mild or severe preeclampsia. Patients with and without PRH were prospectively identified. The association between weight gain category and development of PRH was analyzed.

Results: We noticed a 1.5-fold higher odds of having PRH with an initial BMI ≥30?kg/m² compared to BMI <30?kg/m² (OR 1.64, 95% CI 1.2–2.2, p?=?0.002). Among obese women, we noted a 2-fold higher odds of having PRH with EWG compared to NWG (OR 2.52, 95% CI 1.2–3.9, p?=?0.012). The increased odds persisted after adjusting for race, chronic hypertension and diabetes, and length of gestation (AOR 2.61, 95% CI 1.4–4.9, p?=?0.003). Among obese women with PRH, those with EWG had a 76% decreased odds of having severe disease compared to NWG (OR?=?0.242 [0.07–0.79], p?=?0.019).

Conclusion: We have demonstrated that EWG among obese patients increases overall risk of PRH.     

Body mass index at 11–13 weeks’ gestation and pregnancy complications in a Southern Chinese population: a retrospective cohort study

Objective: To assess the association between body mass index (BMI) and adverse pregnancy outcomes.

Materials and methods: A multicentre retrospective cohort study was conducted in three hospitals in Hong Kong including 67,248 women with singleton pregnancy at 11–13 weeks between 2010 and 2016. The relationship between maternal BMI and (1) miscarriage or stillbirth, (2) development of preeclampsia (PE), (3) gestational hypertension (GH), (4) development of gestational diabetes mellitus (GDM), (5) spontaneous preterm delivery (sPTD) <34 and <37 weeks, (6) delivery of a small for gestational age (SGA) or large for gestational age (LGA) neonate, (7) caesarean section (CS), and (8) postpartum haemorrhage (PPH) were examined after adjusting for confounding factors.

Results: The prevalence of maternal overweight (BMI 25–29.9?kg/m²) and obesity (BMI ≥30?kg/m²) were 13.2% and 2.9%, respectively. Women with a BMI ≥30?kg/m² were nine times more likely to develop GH (95%CI 7.3–11.7), five times more likely to develop PE (95%CI 4.3–6.8) and GDM (95%CI 5.0–6.5) and 1.5–2 times more likely to deliver SGA/LGA neonate. sPTD, required delivery by CS and developed PPH, than those with a BMI of 18.5–22.9?kg/m², and that maternal underweight (BMI <18.5?kg/m²) significantly reduced the risk of GDM, delivery by CS, and PPH. Increased risk of subsequent development of adverse outcomes was observed when BMI was ≥23.0?kg/m².

Conclusions: Maternal overweight and obesity are associated with an increased risk for subsequent development of various pregnancy complications. The need of increased awareness and health surveillance is essential when BMI ≥23?kg/m².     

Impact of pre-gravid body mass index and body mass index change on preeclampsia and gestational diabetes in singleton and twin pregnancies

Abstract

Objective: To examine pre-gravid body mass index (BMI) and gestational BMI change impact on preeclampsia and gestational diabetes mellitus (GDM).

Methods: Retrospective population-based cohort study. Data from Slovenian National Perinatal Information System were analyzed for the period 2002–2011. Three singleton controls were matched by parity and maternal age to each twin pregnancy delivered at >36 weeks. Student’s t test was used to compare pre-gravid BMI and gestational BMI change in different groups (p?<?0.05 significant).

Results: 2046 twin and 6138 singleton pregnancies were included. Twin and singleton patients with preeclampsia or GDM had higher pre-gravid BMI (p?<?0.001). Gestational BMI change was smaller in twins with GDM (p?<?0.001), and not associated with preeclampsia (p?=?0.07). Smaller gestational BMI change in singleton pregnancies was associated with GDM (p?<?0.001), and greater BMI change with preeclampsia (p?=?0.004).

Conclusions: Pre-gravid BMI is more strongly associated with preeclampsia and GDM in twin and singleton pregnancies than gestational BMI change. Smaller gestational BMI change in GDM pregnancies reflect the importance of dietary counseling.     

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.     

Dose–response association between maternal body mass index and small for gestational age: a meta-analysis

Objective: This study was performed to determine the dose–response relationships between maternal anthropometric variables and risk of small for gestational age (SGA).

Methods: Linear and nonlinear dose–response meta-analyses were performed to summarize the adjusted relative risks of SGA. Ten databases, including PubMed (MEDLINE), were searched. Study quality was assessed using the Newcastle–Ottawa scale.

Results: A total of 323 243 subjects were extracted from high-quality studies to evaluate maternal body mass index (BMI) (n?=?9). The generalizability of the findings regarding height and weight (n?=?3 and 2, respectively) was limited. The non-linear model (p for non-linearity 2). The slope of the dose–response curve between maternal BMI and SGA (i.e. the amount of reduction in SGA risk) decreased gradually.

Conclusions: SGA risk may be reduced by increasing BMI of normal (i.e. 18.5?kg/m^2?≤ BMI?2) and overweight women (i.e. 25?kg/m^2?≤?BMI?2), but the most marked reduction is achieved by increasing BMI of underweight women (i.e. BMI?2).     

Maternal pre-pregnancy overweight status and obesity as risk factors for cesarean delivery

Objective.?To determine the extent to which, if at all, maternal pre-pregnancy adiposity and other anthropometric factors are related to risk of cesarean delivery.

Methods.?This hospital-based prospective cohort study included 738 nulliparous women who initiated prenatal care prior to 16 weeks gestation. Participants provided information about their pre-pregnancy weight and height and other sociodemographic and reproductive covariates. Labor and delivery characteristics were obtained from maternal and infant medical records. Risk ratios (RR) and 95% CI were estimated by fitting generalized linear models.

Results.?The proportion of cesarean deliveries in this population was 26%. Women who were overweight (BMI 25.00–29.99?kg/m²) were twice as likely to deliver their infants by cesarean section as lean women (BMI <?20.00?kg/m²) (RR?=?2.09; 95% CI 1.27–3.42). Obese women (BMI ??30.00?kg/m²) experienced a three-fold increase in risk of cesarean delivery when compared with this referent group (RR?=?3.05; 95% CI 1.80–5.18). The joint association between maternal pre-pregnancy overweight status and short stature was additive. When compared with tall (height ??1.63?m), lean women, short (?<?1.63?m), overweight (BMI ??25.00?kg/m²) women were nearly three times as likely to have a cesarean delivery (RR?=?2.79; 95% CI 1.72–4.52).

Conclusion.?Our findings suggest that nulliparous women who are overweight or obese prior to pregnancy, and particularly those who are also short, have an increased risk of delivering their infants by cesarean section.     

The incidence and impact of increased body mass index on maternal and fetal morbidity in the low-risk primigravid population

Objective. To determine the incidence and impact of increased body mass index (BMI) on maternal and fetal morbidity in the low-risk primigravid population.

Methods. This was a prospective study with retrospective analysis of delivery outcome data. All low-risk primigravida who met the inclusion criteria during the recruitment period were approached. BMI was calculated using the formula weight/height squared. The participants were divided into five categories: ‘underweight’ (BMI <20 kg/m²), ‘normal’ (BMI 20.01–25 kg/m²), ‘overweight’ (BMI 25.01–30 kg/m²), ‘obese’ (BMI 30.01–40 kg/m²), and ‘morbidly obese’ (BMI >40 kg/m²). Maternal outcomes evaluated included gestation at delivery, onset of labor (spontaneous/induced/elective cesarean section), length of labor, use of oxytocin and epidural, mode of delivery, and estimated blood loss. Perinatal outcome measures included infant birth weight (kg) and centile, gestational age, ponderal index, Apgar score <7 at 5 minutes, cord pH <7.1, presence of meconium grade 3 at delivery, degree of resuscitation required, admission to neonatal intensive care unit (NICU), and duration of stay.

Results. One thousand and eleven women participated in the study. Complete outcome data were available for 833 women (82%). A significant difference was identified in gestation at delivery between the subgroups (p < 0.004). A significant positive correlation was identified between cesarean section rates with increasing BMI, even when gestation was controlled for (p = 0.004). Similarly, women in the normal BMI group remained significantly less likely to have an infant requiring NICU admission than obese women (2.2% vs. 8.6%; p = 0.011).

Conclusion. High BMI is associated with longer gestations, higher operative delivery rates, and an increased rate of neonatal intensive care admission.     

Prepregnancy body mass index is an independent risk factor for gestational hypertension,gestational diabetes,preterm labor,and small- and large-for-gestational-age infants

Objective: We examined if prepregnancy body mass index (BMI) is a risk factor for gestational hypertension, gestational diabetes, preterm labor, and small-for-gestational-age (SGA) and large-for-gestational-age (LGA) infants with consideration of gestational weight gain, to document the importance of preconception versus prenatal stage.

Methods: We used the data of 219?868 women from 2004 to 2011 Pregnancy Risk Assessment Monitoring System (PRAMS). Multivariate logistic regression analyses were performed to examine the effect of prepregnancy BMI for gestational hypertension, gestational diabetes, preterm labor, and SGA and LGA infants with consideration of gestational weight gain.

Results: Regardless of gestational weight gain, women with obese prepregnancy BMI (≥30?kg/m²) had increased odds of gestational hypertension (adjusted odds ratios (AOR)?=?2.91; 95% CI?=?2.76–3.07), gestational diabetes (2.78; 2.60–2.96), and LGA (1.87; 1.76–1.99) compared to women with normal prepregnancy BMI (18.5–24.9?kg/m²). Women with underweight prepregnancy BMI (<18.5?kg/m²) had increased odds of preterm labor (1.25; 1.16–1.36) and SGA infants (1.36; 1.25–1.49), but decreased odds of LGA infants (0.72; 0.61–0.85) in reference to women with normal prepregnancy BMI (18.5–24.9?kg/m²).

Conclusions: Regardless of adequacy of gestational weight gain, the risk of gestational hypertension, gestational diabetes, and LGA infants increases with obese prepregnancy BMI, whereas that of preterm labor and SGA infants increases with underweight prepregnancy BMI. Preconception care of reproductive aged women is as important as prenatal care to lower the risk of gestational hypertension, gestational diabetes, preterm labor, and SGA and LGA infants.     

Induction of labor with an unfavorable cervix: how does BMI affect success?‡

Objective: Obesity places women and their babies at risk for obstetric and perinatal morbidity including induction of labor and cesarean delivery. We sought to evaluate the impact of body mass index (BMI) on successful induction of labor using misoprostol at our institution. The primary outcome was time to delivery. Secondary outcomes were number of doses of misoprostol, duration of oxytocin and cesarean delivery.

Methods: A retrospective cohort over two years found 329 patients who were >?37 weeks of gestational age and had a Bishop score <?5 prior to beginning induction. Patients were divided into three categories based on their BMI: Group 1: BMI?≤?30 kg/m², Group 2: BMI 30 to 39.9 kg/m² and Group 3: BMI?≥?40 kg/m². Statistical analysis included the use of multivariate analysis, contingency tables and Chi-square tests for categorical data and Pearson’s correlation coefficient for numerical data.

Results: There were no significant differences among the groups when analyzed for gestational age, bishop score, median parity or race. Time to delivery increased significantly with increasing BMI (p?<?0.01). Furthermore, women with higher BMIs required more doses of misoprostol (p?<?0.01), longer duration of oxytocin administration prior to delivery (p?<?0.02) and increased risk of cesarean section (p?<?0.0006).

Conclusion: As BMI increases, obese patients undergoing induction with misoprostol have a longer time to delivery, require more doses of misoprostol, require a longer duration of oxytocin and have higher cesarean delivery rate.     

Pre-pregnancy body mass index (BMI) and cerclage success

Objective: This study was performed to evaluate the effect of pre-pregnancy body mass index (BMI) on the success of cerclage.

Materials and methods: A retrospective cohort study of women who had a history-indicated (HIC) or ultrasound-indicated cerclage (UIC) placed between 1994 and 2011. Based on pre-pregnancy BMI (World Health Organization criteria), three cohorts were defined: normal/overweight (BMI: 20.0–29.9?kg/m²), obese class I/II (BMI: 30.0–39.9?kg/m²) and obese class III (BMI?≥?40.0?kg/m²). The primary outcome was spontaneous preterm birth (sPTB) <35 weeks. The secondary outcomes included but were not limited to gestational age of delivery, sPTB <37, <32 and <28 weeks, preterm premature rupture of membranes and birth weight.

Results: 375 women were included for analysis. Demographics were similar in the three BMI categories, except black race (p?=?0.01). The rates of sPTB <35 weeks were similar between each cohort: 24.3%, 23.0% and 27.7%, respectively (p?=?0.81). BMI was not a predictor of any of the secondary outcomes. A HIC was placed in 47.2% and an UIC was placed in 52.8% women. Both unadjusted and adjusted analysis showed no significant difference in sPTB <35 weeks between BMI categories overall or by cerclage type (HIC or UIC).

Conclusions: Pre-pregnancy BMI is not a significant predictor of sPTB <35 weeks in women with HIC or UIC.     

Do normal-weight women pregnant with twins are at the lowest risk of developing preeclampsia?

Objective: To determine the relation between preeclampsia (PE) and pregravid body mass index (BMI) in twin pregnancy.

Methods: Retrospective cohort study of 542 women pregnant with twins.

Results: Forty-nine patients developed PE (9%). Underweight, overweight and obese women were at a higher risk of PE than normal-weight mothers. There was no linear (p?=?0.7) but significant U-shaped relation between BMI and PE (p?2.

Conclusions: Nonlinear relation between PE occurrence and BMI suggests that using homogeneous PE risks of BMI groups may be incorrect.     

Gestational weight gain in overweight and obese women enrolled in a healthy lifestyle and eating habits program

Abstract

Objectives: To determine whether changes in lifestyle in women with BMI?>?25 could decrease gestational weight gain and unfavorable pregnancy outcomes.

Methods: Women with BMI?>?25 were randomized at 1st trimester to no intervention or a Therapeutic Lifestyle Changes (TLC) Program including diet (overweight: 1700?kcal/day, obese: 1800?kcal/day) and mild physical activity (30?min/day, 3 times/week). At baseline and at the 36th week women filled-in a Food Frequency Questionnaire. Outcomes: gestational weight gain, gestational diabetes mellitus, gestational hypertension, preterm delivery. Data stratified by BMI categories.

Results: Socio-demographic features were similar between groups (TLC: 33 cases, Controls: 28 cases). At term, gestational weight gain in obese women randomized to TLC group was lower (6.7?±?4.3?kg) versus controls (10.1?±?5.6?kg, p?=?0.047). Gestational diabetes mellitus, gestational hypertension and preterm delivery were also significantly lower. TLC was an independent factor in preventing gestational weight gain, gestational diabetes mellitus, gestational hypertension. Significant changes in eating habits occurred in the TLC group, which increased the number of snacks, the intake of fruits–vegetables and decreased the consumption of sugar.

Conclusions: A caloric restriction associated to changes in eating behavior and constant physical activity, is able to reduce gestational weight gain and related pregnancy complications in obese women.