The effects of maternal obesity on perinatal outcomes among those born small for gestational age*

Background: Maternal obesity has been associated with higher birth weight. Small for gestational age (SGA) neonates born to obese women may be associated with pathological growth with increased neonatal complications.

Methods: This was a retrospective cohort study of all non-anomalous singleton neonates born in Texas from 2006–2011. Analyses were limited to births between 34 and 42 weeks gestation with birth weight?≤10th percentile. Results were stratified by maternal pre-pregnancy BMI class. The risk for stillbirth, neonatal death, neonatal intensive care unit (NICU) admission and five?minute Apgar scores?<7 were estimated for each obesity class and compared to the normal weight group. Multivariable logistic regression analyses were performed to control for potential confounding variables.

Results: The rate of stillbirth was 1.4/1000 births for normal weight women, and 2.9/1000 among obese women (p?0.001, aOR: 1.83 [1.43, 2.34]). The rate of neonatal deaths among normal weight women was 4.3/1000 births, whereas among obese women it was 4.7/1000 (p?=?0.94, aOR: 1.10 [0.92, 1.30]). A dose-dependent relationship between maternal obesity and stillbirths was seen, but not for other neonatal outcomes.

Conclusion: Among SGA neonates, maternal pre-pregnancy obesity was associated with increased risks for stillbirth, NICU admission and low Apgar scores but not neonatal death.     

Could maternal pre-pregnancy body mass index affect Apgar score?

Objective

Obesity is one of global health problems and maternal obesity may be associated with increase in risk of pregnancy complications and neonatal death. The purpose of this study was to evaluate the effect of maternal pre-pregnancy body mass index (BMI) on neonate Apgar score at minute 5.

Methods

In a retrospective cohort study, Apgar score at minute 5 of all singleton term babies of nulliparous women whom were delivered in Shahid Sadoughi Hospital, Yazd, Iran, from 2007 to 2009 were evaluated. Body mass index (BMI: weight in kg/height in m²) of the mothers were calculated and BMI less than 18.5, 18.5–24.9, 25–29.9 and more than 30 were considered underweight, normal, overweight and obesity, respectively. Neonatal Apgar score of 3–7 and less than three was considered as low and very low Apgar score, respectively.

Results

Eighty-eight (2.8 %) women were underweight, 1,401 (44.9 %) normal weight, 1,389 (44.5 %) overweight and 242 (7.8 %) were obese. 477 (15.3 %) and 31(0.7 %) neonates had low and very low Apgar score, respectively at minute 5. Logistic regression analysis showed maternal overweight [in odd ratio of 3.7, 95 % CI 2.4–4.6] and obesity [in odd ratio of 13.4, 95 % CI 9.7–14.1] were risk factors of neonatal low Apgar score, but they had not any statistically significant effect on neonatal very low Apgar score.

Conclusion

Maternal pre-pregnancy overweight should be more concerned to prevent complication of low Apgar score in their newborns.     

Maternal pre-pregnancy body mass index and the risk for gestational diabetes mellitus in women with twin pregnancy in South Korea

ObjectiveTo investigate the association between maternal pre-pregnancy body mass index (BMI) and the risk for gestational diabetes mellitus (GDM) in women with twin pregnancy in South Korea.Materials and methodsWe performed a single-center, retrospective cohort study involving 1028 women with twin pregnancy from January 2006 to December 2018 in South Korea. Pregnancies with monoamnionic twins, twin–twin transfusion syndrome, fetal death in utero before 24 weeks, pre-gestational diabetes mellitus, and unknown BMI or GDM status were excluded. Subjects were grouped into four groups based on pre-pregnancy BMI: underweight (<18.5 kg/m²), normal (18.5–22.9 kg/m²), overweight (23.0–24.9 kg/m²), and obese (≥25.0 kg/m²).ResultsAmong 1028 women who were included in the analysis, 169 (16.4%), 655 (63.7%), 111 (10.8%), and 93 (9.0%) women were underweight, normal, overweight, and obese, respectively, before pregnancy. The incidence of GDM was 8.9% in the total study population: 4.7%, 8.2%, 11.7%, and 17.2% in the underweight, normal, overweight, and obese group, respectively (p = 0.005). The incidence of GDM significantly increased according to the increase in pre-pregnancy BMI (p < 0.001). Women in the obese group were more likely to be affected by GDM compared to the normal group (adjusted odds ratio = 2.20, 95% confidence interval = 1.19–4.08) after controlling for maternal age, parity, type of conception, and chorionicity.ConclusionIn twin pregnancies in South Korea, the risk of GDM increased as maternal pre-pregnancy BMI increased and obese women before pregnancy were more likely to be affected by GDM.     

The effect of maternal obesity on pregnancy outcomes in women with gestational diabetes

Objective.?To examine the impact of maternal obesity on maternal and neonatal outcomes in pregnancies complicated with gestational diabetes mellitus (GDM).

Methods.?Women with singleton pregnancies and GDM enrolled in an outpatient GDM education, surveillance and management program were identified. Maternal and neonatal pregnancy outcomes were compared for obese (pre-pregnancy BMI?≥?30?kg/m²) and non-obese (pre-pregnancy BMI?<?30?kg/m²) women and for women across five increasing pre-pregnancy BMI categories.

Results.?A total of 3798 patients were identified. Maternal obesity was significantly associated with the need for oral hypoglycemic agents or insulin, development of pregnancy-related hypertension, interventional delivery, and cesarean delivery. Adverse neonatal outcomes were also significantly increased including stillbirth, macrosomia, shoulder dystocia, need for NICU admission, hypoglycemia, and jaundice. When looking across five increasing BMI categories, increasing BMI was significantly associated with the same adverse maternal and neonatal outcomes.

Conclusion.?In women with GDM, increasing maternal BMI is significantly associated with worse maternal and neonatal outcomes.     

Maternal BMI in Twin Pregnancies and Impact on Neonatal Outcomes in the Level I Unit: A Retrospective Cohort Study

ObjectiveWith maternal obesity rates and twin pregnancies on the rise, the aim of this study was to assess the impact of pre-pregnancy or first trimester BMI on short-term neonatal morbidities in twins admitted to a level I unit.MethodsThis retrospective single-centre cohort study was conducted on twins born between January 1, 2010 and December 31, 2013 and admitted to the level I unit at Mount Sinai Hospital in Toronto, Ontario. Twin pairs were categorized according to maternal BMI: underweight (<18.5 kg/m²), normal weight (18.5–24.9 kg/m²), overweight (25.0–29.9 kg/m²), and obese (≥30 kg/m²). The primary outcome was combined neonatal morbidities of hypoglycemia and hyperbilirubinemia. The secondary outcome was length of hospital stay. All outcomes were compared between twins in various BMI groups, and data were analyzed using the chi-square test or ANOVA (Canadian Task Force Classification II-2).ResultsData on 700 neonates born to 350 women were analyzed. Baseline maternal and neonatal characteristics were similar between the groups, except for a statistically significantly higher incidence of maternal hypertension (P < 0.02) and a trend towards increased gestational diabetes rates (P = 0.05) in women with overweight or obesity compared with women with underweight or normal weight. No association was noted between maternal BMI and occurrence of neonatal hypoglycemia, hyperbilirubinemia, and length of stay in either twin pair (P > 0.05)ConclusionMaternal BMI had no detectable effect on neonatal morbidities and length of stay in twins admitted to the level I unit in the study centre.     

Interpregnancy body mass index changes and risk of stillbirth

Background/Aims: To examine the association between interpregnancy body mass index (BMI) change and stillbirth. Methods: Retrospective study using Missouri maternally linked cohort files (1978-2005). A total of 218,389 women were used in the analysis. BMI was classified as: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), or obese (≥30.0). Weight change was defined based on BMI category (i.e. normal-normal, normal-obese, etc.). Cox proportional hazard regression models were used to generate adjusted hazard ratios (HR) and 95% CI for the risk of stillbirth in the second pregnancy. Results: Significant findings were associated with interpregnancy BMI changes involving overweight mothers becoming obese (HR = 1.4, 95% CI 1.1-1.7), normal-weight mothers becoming overweight (HR = 1.2, 95% CI 1.0-1.4) or obese (HR = 1.5, 95% CI 1.1-2.1), or obese mothers maintaining their obesity status across the two pregnancies (HR = 1.4, 95% CI 1.2-1.7). Other weight change categories did not show significant risk elevation for stillbirth. Conclusions: BMI change appears to play an important role in subsequent stillbirth risk.     

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 combined effect of maternal smoking and obesity on the risk of preeclampsia

AIMS: Cigarette smoking during pregnancy is associated with a lower risk of preeclampsia, whereas obesity increases the risk of preeclampsia. We sought to assess the combined effect of smoking and obesity on the risk of preeclampsia. METHODS: We conducted a population-based cohort study of 129,674 women who delivered singleton infants during 2000-2001. Data for cigarette use, pre-pregnancy body mass index (BMI), preeclampsia, and potential confounders were obtained from birth certificate files. Mantel-Haenszel stratified analysis and logistic regression were used to analyze the data. RESULTS: The preeclampsia risk was 3.1, 4.5, 7.6 and 8.8% for normal weight (BMI 18.5-24.9), overweight (25.0-29.9), obese (30.0-39.9) and morbidly obese (>or=40.0 kg/m2) women, respectively, who smoked cigarettes while pregnant. The preeclampsia risk was 3.9, 6.2, 9.0 and 12.3% for the same groups of women, respectively, who did not smoke during their pregnancy. Compared to non-smokers, the relative risk of preeclampsia for women who smoked cigarettes was 0.78 (95% confidence interval 0.73-0.83) before and after adjusting for pre-pregnancy BMI and other factors associated with preeclampsia. CONCLUSION: The risk of preeclampsia is lower for women who smoke cigarettes while pregnant regardless of their pre-pregnancy BMI.     

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.     

Extreme obesity and risk of stillbirth among black and white gravidas

OBJECTIVE: To estimate the risk for stillbirth among three generally accepted obesity subtypes based on severity. METHODS: We used the Missouri maternally linked cohort data containing births from 1978 to 1997. Using prepregnancy weight and height, mothers were classified on the basis of calculated body mass index (BMI) above 30 into three subsets: class I (30-34.9), class II (35-39.9), and extreme obesity (greater than or equal to 40). Using normal-weight, white women (18.5-24.9) as a reference, we applied Cox proportional hazard regression models to estimate risks for stillbirth. RESULTS: The prevalence of obesity in pregnant women was 9.5% (12.8% among blacks and 8.9% among whites). Overall, obese mothers were about 40% more likely to experience stillbirth compared with nonobese gravidas (adjusted hazard ratio 1.4; 95% confidence interval [CI] 1.3-1.5). The risk for stillbirth increased in a dose-dependent fashion with increase in BMI: class I (adjusted hazard ratio 1.3; 95% CI 1.2-1.4); class II (adjusted hazard ratio 1.4; 95% CI 1.3-1.6) and extreme obesity (adjusted hazard ratio 1.9; 95% CI 1.6-2.1; P for trend <.01). Obese black mothers experienced more stillbirths than their white counterparts (adjusted hazard ratio 1.9; 95% CI 1.7-2.1 compared with adjusted hazard ratio 1.4; 95% CI 1.3-1.5). The black disadvantage in stillbirth widened with increase in BMI, with the greatest difference observed among extremely obese black mothers (adjusted hazard ratio 2.3; 95% CI 1.8-2.9). CONCLUSION: Obesity is a risk factor for stillbirth, particularly among extremely obese, black mothers. Strategies to reduce black-white disparities in birth outcomes should consider targeting obese, black women. LEVEL OF EVIDENCE: II.     

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.     

Abnormal maternal body mass index and obstetric and neonatal outcome

Objective.?The objective of this study is to examine the effects of abnormal maternal body mass index (BMI), either underweight or severe or morbid obesity (BMI >35), on obstetrical and neonatal outcomes.

Methods.?A three-year period (2.007–2.009) observational retrospective study was carried out in Granada (Spain). Women were categorized by first ten weeks of pregnancy BMI, according to World Health Organization (WHO) into three groups: underweight (<18.5), normal (20–24.9), and severe or morbid obese (>35). Obstetrical and neonatal outcomes were evaluated using normal group as reference after suitable adjustments for confounding factors.

Results.?3.016 patients out of 12.781 single births were included. Maternal BMI classified 168 women (5.5 %) as underweight, 2.597 (86.1%) as normal, and 251 (8.3%) as severe or morbidly obese. As compared to normal women, underweight women were younger, and class II or III obese showed higher parity and higher incidence of hypertension disorders and Diabetes Mellitus. After controlling for these confounders, underweight women showed increased adjusted risk of oligohydramnios and low birth weight babies, and severe or morbidly obese women had an increased adjusted risk of Streptococcus Group B colonization, induction of labour, elective and emergency cesarean section, fetal macrosomia, fetal acidosis at birth, and perinatal mortality.

Conclusions.?Severe or morbid obesity were associated with an increased risk of adverse perinatal outcome and mortality and should be managed as high-risk pregnancies.     

Prepregnancy obesity and fetal death: a study within the Danish National Birth Cohort

OBJECTIVE: To examine the association between high prepregnancy body mass index and fetal death, allowing for the effects of gestational age, weight gain, and maternal diseases in pregnancy. METHODS: Prepregnancy body mass index (BMI) and fetal death were examined in the Danish National Birth Cohort among 54,505 pregnant women who participated in a comprehensive interview during the second trimester. Pregnancy outcomes were obtained from registers and medical records. Cox regression analyses with delayed entry and time-dependent covariates were used to estimate the risk of fetal death. RESULTS: Compared with normal-weight women (18.5 < or = BMI < 25), the risks of fetal death among obese women (BMI > or = 30), expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were as follows: before week 14: 0.8 (0.5-1.4), weeks 14-19: 1.6 (1.0-2.5), weeks 20-27: 1.9 (1.1-3.3), weeks 28-36: 2.1 (1.0-4.4), weeks 37-39: 3.5 (1.9-6.4), and weeks 40+: 4.6 (1.6-13.4). Overweight women (25 < or = BMI < 30) also experienced a higher risk after 28 weeks, and especially after 40 weeks of gestation (HR 2.9, 95% CI 1.1-7.7). Analysis of stillbirth (fetal death at 28+ completed weeks of gestation) indicated that the effects were not due to obesity-related diseases in pregnancy, nor was weight gain associated with stillbirth. The increased risk of stillbirth among overweight and obese women was partly attributable to inadequate placental function (crude odds ratios 2.1, 95% CI 1.0-4.4, and 5.2, 95% CI 2.5-10.9, respectively). CONCLUSION: Prepregnancy obesity was associated with an increasing excess risk of fetal death with advancing gestation, and placental dysfunction may be a possible contributing factor.     

Maternal obesity and stillbirth

The current obesity epidemic appears to contribute significantly to adverse fetal outcomes, and in this work we compile up-to-date evidence for the link between maternal obesity and risk of stillbirth. The review revealed a preponderance of evidence showing that the risk of stillbirth is increased among obese mothers with amplified risk estimates as the severity of obesity increases. Changes in interpregnancy body mass index (BMI) influence subsequent fetal survival and obese women that normalize their BMI values experience enhanced fetal survival in future pregnancies. The elevated risk of stillbirth among obese mothers affect all gestations regardless of fetal number, with the most profound risk (4-fold increase) noted among triplet gestations. The literature has predominantly reported a strong association between maternal prepregnancy obesity and stillbirth. The considerable magnitude of association, consistency of positive results for the association between maternal obesity and stillbirth, the establishment of temporality between maternal obesity and stillbirth, the incremental elevation in risk with ascending BMI values, as well as the improvement in fetal survival with decrease in interpregnancy BMI among obese mothers strongly provide sufficient evidence that the relationship between maternal obesity and stillbirth may be causal.     

Pregnancy outcome and prepregnancy body mass index in 2459 glucose-tolerant Danish women

OBJECTIVE: This study was undertaken to investigate the relationship between pregnancy outcome and prepregnancy overweight or obesity in women with a normal glucose tolerance test. STUDY DESIGN: A historical cohort study of 2459 pregnant women systematically examined for gestational diabetes was performed. Information of oral glucose tolerance test results and clinical outcome were collected from medical records. RESULTS: The risk of hypertensive complications, cesarean section, induction of labor and macrosomia was significantly increased in both overweight women (body mass index [BMI] 25.0-29.9 kg/m(2)) and obese women (BMI >or= 30.0 kg/m(2)) compared with women who were of normal weight (BMI 18.5-24.9 kg/m(2)). The frequencies of shoulder dystocia, preterm delivery, and infant morbidity other than macrosomia were not significantly associated with maternal BMI. CONCLUSION: Prepregnancy overweight and obesity is associated with adverse pregnancy outcome in glucose-tolerant women.     

Gestational bodyweight gain among underweight Japanese women related to small-for-gestational-age birth

Aim: The prevalence of underweight women, who have an increased risk for small-for-gestational-age (SGA) birth, is increasing in Japan. We examined the associations of pre-pregnancy body mass index and gestational weight gain (GWG) with SGA birth among Japanese women. Material and Methods: We conducted a prospective cohort study of 1391 women who delivered full-term singleton babies. SGA was defined as below the 10th percentile of birthweight at each gestational age, baby sex, and parity. We calculated the 5th percentile of birthweight in the same way for another threshold for SGA. According to pre-pregnancy body mass index, we divided the participants into three groups: underweight (<18.5?kg/m(2) ), normal weight (18.5-24.9?kg/m(2) ), and overweight and obese (≥25.0?kg/m(2) ). Results: SGA birth was observed most frequently among the underweight group (13.8%). Underweight was associated with an increased risk of SGA birth. The multiple-adjusted odds ratio for underweight was 1.96 (95% confidence interval, 1.23-3.11) compared with normal weight. Sufficient GWG reduced the incidence and the multiple-adjusted odds ratio for 1-kg increase of GWG was 0.86 (0.81-0.92). The same tendency was observed for the delivery of infants below the 5th birthweight percentile. Women with underweight and normal weight who had 9.0?kg or less of GWG had a significantly higher risk of SGA birth than women with normal weight who had 9.1-11.0?kg of GWG. Conclusions: Underweight and poor GWG were associated with a higher incidence of SGA birth. However, the incidence of SGA birth among underweight women was not increased significantly if they had sufficient GWG.     

Association between maternal weight gain and birth weight

OBJECTIVE: To investigate the association between maternal weight gain and birth weight less than 3,000 g and greater than or equal to 4,000 g in underweight (body mass index [BMI] less than 19.8 kg/m(2)), normal weight (BMI 19.8-26.0 kg/m(2)), overweight (BMI 26.1-29.0 kg/m(2)), and obese (BMI greater than 29.0 kg/m(2)) women, with emphasis on the use of the American Institute of Medicine (IOM) recommendations in Denmark. METHODS: We analyzed data from 2,248 women with singleton, term pregnancies. The relationship between weight gain and risk of birth weight less than 3,000 g and greater than or equal to 4,000 g was examined in the four BMI groups, and use of IOM recommendations was tested by logistic regression analyses. RESULTS: We found an inverse relationship between maternal weight gain and the proportion of infants with a birth weight less than 3,000 g. Birth weight greater than or equal to 4,000 g increased with an increasing weight gain in underweight and normal-weight women, but the association was less apparent in overweight and obese women. Underweight women seemed to benefit from gaining more weight than recommended by the IOM, because the odds ratio (OR) of birth weight less than 3,000 g was 0.3 (95% confidence interval [CI] 0.1-0.9) and the OR was 1.7 for birthweight greater than or equal to 4,000 g (95% CI 0.8-3.6). The normal-weight women had an increased risk of birth weight less than 3,000 g (OR 2.4, 95% CI 1.5-3.7) if weight gain was below the recommended range, and the OR of birth weight greater than or equal to 4,000 g was 1.9 (95% CI 1.5-2.5) when the women gained more than recommended. CONCLUSION: The IOM recommendations may provide a basis for Danish recommendations to pregnant women, although the upper recommended limit for underweight women may have to be increased.     

To evaluate the effect of pre-pregnancy body mass index on maternal and perinatal outcomes among adolescent pregnant women

Objective: To evaluate the effect of pre-pregnancy body mass index on maternal and perinatal outcomes among adolescent pregnant women.

Methods: We conducted this prospective cross-sectional study on 365 singleton adolescent pregnancies (aged between 16 and 20 years) at a Maternity Hospital, between December 2014 and March 2015. We divided participants into two groups based on pre-pregnancy body mass index (BMI): overweight and obese adolescent (BMI at or above 25.0?kg/m) and normal weight (BMI between 18.5 and 24.99?kg/m) adolescent. 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/obesity and normal weight was 34.6% (n?=?80) and 65.4% (n?=?261) in the study population, respectively. Compared with normal-weight teens (n?=?234), overweight/obese teens (n?=?71) were at higher risk for cesarean delivery (odds ratio [OR] 0.7, 95% confidence interval [CI] 0.4–1.4), preeclampsia (adjusted odds ratio [OR] 0.1, 95% confidence interval [CI] 0.02–0.9) and small of gestational age (odds ratio [OR] 0.2, 95% confidence interval [CI] 0.1–0.9).

Conclusion: BMI increased during pre-pregnancy could be an important preventable risk factor for poor obstetric complications in adolescent pregnancies, and for these patients prevention strategies (e.g., nutritional counseling, weight-loss, regular physical activity) for obesity are recommended before getting pregnant.     

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.     

孕前体重指数对糖筛选异常孕妇妊娠结局的影响

目的：探讨孕前体重指数对单纯50g糖筛选阳性的孕妇母儿预后的影响。方法：选取2000年1月至2006年12月在上海第一人民医院行50g糖筛选异常而75g葡萄糖耐量试验结果正常的孕妇655例为研究对象,按孕前体重指数（BMI）分为3组：A：消瘦组（〈18.5kg/m^2）,B：体重正常组（18.5~24.9kg/m^2）,C.超重及肥胖组（〉25kg/m^2）,比较3组孕妇的妊娠结局。结果：655例孕妇中,A组95例（14.5%）,B组483例（73.7%）,C组77例（11.8%）。与B组相比,C组孕妇发生妊娠不良结局的危险度增高,其中子痫前期OR为3.58（95%Cl2.28~9.98）,早产OR3.64（95%Cl1.73~7.67）,巨大儿OR1.49（95%Cl1.23~3.01）,低出生体重儿OR2.55（95%Cl1.03~6.32）,新生儿低血糖OR4.07（95%Cl2.31~12.78）;A组发生低出生体重儿的几率增加,为2.70（95%Cl1.66~4.40）。结论：孕前体重指数是影响妊娠结局的独立因素。