Effects of erythromycin on pregnancy duration and birth weight in lipopolysaccharide-induced preterm labor in pregnant rats

OBJECTIVE: The aim of this study was to investigate the effects of erythromycin on pregnancy duration and on live birth weight in lipopolysaccharide (LPS)-induced preterm labor model in rats. STUDY DESIGN: Total of 60 pregnant rats on day 16 of gestation was intraperitoneally injected with 25 microg/kg LPS. Animals were randomly divided into six groups and 20mg/kg (n=10), 40 mg/kg (n=10), 60 mg/kg (n=10), 80 mg/kg (n=10), and 100mg/kg (n=10) erythromycin and equal volume of physiological saline (n=10) were given intraperitoneally. Injection of LPS-to-vaginal bleeding interval, vaginal bleeding-to-delivery interval, LPS injection-to-delivery interval was monitored and live birth weight of neonates was determined. Statistical analysis was performed using Kruskal-Wallis, Mann-Whitney U-test and Spearman correlation analysis. RESULTS: Intraperitoneal injection of erythromycin to LPS-administered rats caused significant increase in latent period, labor period, total period and live birth weight in a dose dependent manner. CONCLUSION: These data shows that erythromycin causes prolongation of pregnancy period and increases live birth weight in LPS-induced preterm labor of pregnant rats.     

Protease inhibitors and decreased birth weight in HIV-infected pregnant women with impaired glucose tolerance.

OBJECTIVE: To assess the impact of highly active antiretroviral therapy, including a protease inhibitor (HAART/PI), on maternal glucose tolerance and fetal growth. STUDY DESIGN: A retrospective chart review of pregnancy outcomes of human immunodeficiency virus-infected pregnant women receiving HAART/PI (n=41) or zidovudine monotherapy (n=23). RESULTS: Abnormal 1-hour glucose tolerance tests (1hGTT) were observed in 30% of subjects receiving HAART/PI between 24 and 28 weeks' gestation. An elevated 1hGTT was associated with a significantly lower mean birth weight in subjects receiving HAART/PI compared to babies born to mothers with a normal 1hGTT (3.40+/-0.09 vs 3.00+/-0.18 kg, p<0.05, ANOVA). CONCLUSION: HAART/PI therapy is associated with an increased rate of impaired glucose tolerance in pregnancy and impaired fetal growth. This finding merits further investigation.     

The relationship between cadmium, zinc, and birth weight in pregnant women who smoke

It is universally accepted that smoking during pregnancy results in decreased infant birth weight. However, the mechanism for decreased birth weight is not completely understood. This study tested the hypothesis that the cadmium/zinc interaction in the maternal-fetal-placental unit of the mother who smokes could be related to birth weight. Thiocyanate was used as the index of smoking status and atomic absorption spectroscopy was used to determine trace elements. Results show that cord vein red blood cell zinc and maternal whole blood cadmium levels are significant predictors of infant birth weight when variance that is due to clinical factors and thiocyanate is controlled with stepwise multiple regression techniques (n = 202). Bivariate correlation techniques showed that the factors affecting birth weight were different in the smoking and nonsmoking groups. For example, in nonsmokers (n = 125), the cord vein red blood cell zinc level was positively related to birth weight. In smokers (n = 77), maternal whole blood cadmium, placental cadmium, and placental zinc levels were negatively related to birth weight; the ratio of placental zinc to placental cadmium and the cord vein red blood cell zinc level were positively related to birth weight. The results suggest that increased maternal cadmium and decreased cord vein red blood cell zinc levels in infants of smokers may be significant clinically since increased maternal whole blood cadmium and decreased cord vein red blood cell zinc levels are both significantly related to decreased birth weight.     

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.     

Effect of maternal weight gain on infant birth weight

OBJECTIVE: To ascertain whether increased weight gain during pregnancy resulted in higher birth weight infants. METHODS: A database was constructed from valid data of a sample of 159 healthy women between 19 to 37 years of age. The inclusion criteria were: maternal age of 19-37 years, term gestations (37-42 weeks), a baseline weight obtained at 0-15 weeks gestation, and a final weight obtained within 2 weeks of delivery. Weight gain was calculated by subtracting baseline weight from the final weight. A documented height enabled calculation of BMI. A negative screen for gestational diabetes was required. RESULTS: Women with lower first trimester BMI (< 25) had infants of lower birth weight than women of higher BMI (> 25). Women with lower gain (< 35 lbs) delivered smaller infants than women with higher gain (> 35 lbs). Women of higher BMI and higher gain delivered the largest infants (F = 5.37; p = 0.0015). Underweight women (BMI < 19) gained less weight than women of normal weight (BMI 19-25), who gained the most weight. Obese women (BMI > 29) gained the least weight (F = 6.26; p = 0.0005). CONCLUSION: The results confirmed that excessive maternal weight gain in pregnancy (> 35 lbs), does result in higher birth weight infants.     

Effects of erythromycin on stretch-induced contractile activity of isolated myometrium from pregnant women

BACKGROUND: Despite the fact that preterm labor and birth account for the vast majority of neonatal morbidity and mortality the currently available treatment options are still far from satisfactory. The aim of this study was to investigate the effects of erythromycin on stretch-induced contractions of pregnant human myometrial strips, obtained at cesarean section. METHOD: Myometrial strips were suspended in an organ bath under 3 g tension and the effects of erythromycin (0.1, 0.2, 0.5, 1.0 mM) on stretch-induced isometric contractions were evaluated. Results were statistically analyzed using Kruskal Wallis analysis of variance and Wilcoxon Rank tests where appropriate. RESULTS: Erythromycin caused a significant decrease in the peak amplitude, while causing an increase in frequency of stretch-induced myometrial contractions in a dose dependent manner in vitro. CONCLUSIONS: Results from this preliminary study suggest that erythromycin may have additional beneficial effects in infection related preterm labor cases, however, further studies are needed for clarifying the usefulness of erythromycin as a tocolytic agent.     

Rate of preterm birth in pregnant women with vitamin E treatment: a population-based study

Objective: Vitamin E is frequently used for prevention/treatment of repeated or threatened abortion and threatened preterm delivery in Hungarian pregnant women, though, internationally this old-fashion method is not recommended. Methods: The rate of preterm birth of newborns in pregnant women with high dose (estimated daily dose 450?mg) vitamin E treatment or without this treatment was compared in the population-based large data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities. Results: Of 38,151 newborns with any defect, 2,287 (6.0%) had mothers with vitamin E treatment. Pregnant women with vitamin E treatment had very high rate of threatened abortion (43.6% vs. 15.4%) and high rate of threatened preterm delivery (27.5% vs. 13.4%) compared to pregnant women without vitamin E treatment. Nevertheless, the gestational age at delivery was 0.2 week longer and rate of preterm births was lower in the newborns of pregnant women with vitamin E treatment (6.6% vs. 9.3%; adjusted OR with 95% CI: 0.71, 0.63–0.84). This preterm preventive effect of vitamin E treatment could not be explained by known confounders, though folic acid/multivitamins also reduced the rate of preterm birth. Conclusion: The study showed nearly 30% reduction in preterm births of pregnant women with vitamin E treatment.     

The effects of maternal weight gain patterns on term birth weight in African-American women

Objective.?The goals of our study were (1) to estimate the trends in maternal weight gain patterns and (2) to estimate the influence of variation in maternal weight and rate of weight gain over different time periods in gestation on variation in birth weight in African-American and non-African-American gravidas.

Study Design and Setting.?Data from a prospective cohort study in which pregnant women were monitored at multiple time points during pregnancy were analysed. Maternal weight was measured at three times during pregnancy: preconception (W₀); 16–20 weeks gestation (W₁); 30–36 weeks gestation (W₂), in a cohort of 435 women with full-term singleton pregnancies. The relationship between gestational age-adjusted birth weight (aBW) and measures of maternal weight and rate of weight gain across pregnancy was estimated using a multivariable longitudinal regression analysis stratified on African-American race.

Results.?The aBW was significantly associated with maternal weight measured at any visit in both strata. For African-American women, variation in aBW was significantly associated with variation in the rate of maternal weight gain in the first half of pregnancy (W₀₁) but not the rate of maternal weight gain in the second half of pregnancy (W₁₂); while for non-African-American women, variation in aBW was significantly associated with W₁₂ but not W₀₁.

Conclusion.?Factors influencing the relationship between aBW and maternal weight gain patterns depend on the context of the pregnancy defined by race. Clinical decisions and recommendations about maternal weight and weight gain during pregnancy may need to account for such heterogeneity.     

Influence of rest during pregnancy on birth weight in working women

OBJECTIVE: Birth weight in Sweden has increased during the past decades. We investigated whether rest provided by the combination of time off from work and social benefits among working pregnant women contributed to the observed changes. METHOD: A total of 7,459 consecutively delivered women in 1978, 1986, 1992, and 1997 at 2 delivery wards in southeastern Sweden were studied. RESULTS: Between 1978 and 1997, the average birth weight among the children of the women studied increased from 3,484 to 3,566 grams (P < .001). The in-crease in weight was most evident among infants born to women who were employed during pregnancy. The use of social benefits and increased rest during pregnancy did not significantly influence birth weight (P = .107), even after adjustment for gestational length, parity, smoking, age, and occupation. CONCLUSION: The continuous increase in infants' birth weight among pregnant women in this study did not correlate with rest periods in the form of leave supported by social benefit programs. The effects of social benefit programs on pregnancy outcome may thus be overrated and merits further research.     

Assessment of maternal-fetal status of some essential trace elements in pregnant women in late gestation: relationship with birth weight and placental weight.

OBJECTIVE: The status of the essential trace elements copper (Cu), iron (Fe), zinc (Zn), selenium (Se) and molybdenum (Mo) has been investigated in maternal and umbilical cord blood in control, uncomplicated pregnancies at term, and the possibility assessed of a relationship between blood levels of these trace elements and newborn weight and placental weight. Fetal-maternal ratios of the elements were also computed to establish baseline values for the Kuwaiti obstetric population. METHODS: Blood samples were collected from a maternal vein, the umbilical artery and umbilical vein of normal pregnant women at the time of spontaneous delivery or Cesarean section, and the concentrations of various trace elements determined by atomic absorption spectrophotometry. RESULTS: The concentration of Cu, Fe, Mo, Se and Zn averaged 2406.1, 3252.1, 11.6, 107.3 and 696.2 microg/l, respectively, in maternal venous blood in the pregnant women (n=39) at term. Umbilical venous/maternal venous ratios of Cu, Fe, Mo, Se and Zn averaged 0.32, 1.96, 1.03, 0.83 and 1.55, respectively. Neonatal birth weight did not correlate with maternal blood levels of the trace elements (p>0.05) in the mother-child pairs studied. However, neonatal weight correlated negatively (p<0.05) with umbilical venous Cu level. Placental weight correlated positively (p<0.05) with Fe and Mo levels and negatively with Zn level in umbilical venous blood. CONCLUSIONS: Our results indicate an active placental transport for Fe and Zn, while Cu, Mo and Se appear to be exchanged passively between mother and fetus. Evaluation of Fe, Mo, Se and Zn levels in maternal and umbilical cord blood does not appear to be useful in the assessment of fetal growth.     

Effect of early sonographic placental maturity on birth weight

Dependence of birth weight from placental maturity could be demonstrated by sonographic judgement of placental structure during pregnancy in 784 pregnant women. Early was children in with low birth weight generally seen placental maturity. In children with birth weight over 3500 grs first findings of placental maturity were in 81.8% after 35 weeks gestation. There may be possible correlations between placental maturity and risk factors typical for low placental perfusion with the consequence of fetal growth retardation as hypertension, hypotension, stress and smoking.     

Inadequate weight gain among pregnant adolescents: Risk factors and relationship to infant birth weight

OBJECTIVE: Our purpose was to identify behavioral markers for inadequate weight gain (<20 pounds) during pregnancy among adolescents <18 years old.STUDY DESIGN: A total of 337 adolescents who were delivered of a term infant at our institution between March 10, 1992, and November 28, 1994 participated in this study. A comprehensive structured interview conducted at the first prenatal visit elicited demographic information and behavioral risk factors. Maternal weights, reproductive history, evidence of sexually transmitted disease, and infant birth weight were extracted from medical records. Logistic regression and χ² analyses compared characteristics and infant birth weights between those who gained <20 pounds with those who gained ≥20 pounds.RESULTS: A total of 11.6% (39/337) of the total sample gained <20 pounds during the pregnancy. Adolescents who gained <20 pounds compared with ≥20 pounds were delivered of significantly lighter (2942 gm vs 3392 gm) infants and were more likely to be delivered of infants weighing <2500 gm (13% vs <1%). Stepwise logistic regression revealed that adolescents who were battered (odds ratio 5.3) or had a sexually transmitted disease (odds ratio 2.3) or an unplanned pregnancy (odds ratio 8.1) were at increased risk for insufficient weight gain during pregnancy.CONCLUSION: Our data suggest that behavioral risk factors are important in the identification of adolescents at greatest risk for inadequate weight gain. Early identification during pregnancy is essential to modify nutritional practices and thus minimize poor obstetric outcomes. (Am J Obstet Gynecol 1997;176:1220-7.)     

Attitudes and awareness towards weight gain among normal weight and overweight pregnant women

Objectives: (1) To evaluate the proportion who correctly classify- or misclassify maternal weight gain; (2) to investigate weight gain attitudes, and (3) to compare weight gain attitudes with weight gain recommendations by the Institute of Medicine (IOM), as well as background and lifestyle factors.

Methods: This is secondary analysis of cohort data collected as part of a prospective study of determinants of macrosomic infants in Norway (the STORKproject). The participants (n?=?467) answered a self-administered questionnaire, including report on maternal weight gain and attitudes towards weight gain, in mean gestation week 36.4 (SD?=?1.7). The women were also weighted (kg) at the hospital using a digital beam scale.

Results: A significant discrepancy was found between self-reported and measured maternal weight gain. About 76% reported to be satisfied with maternal weight gain while 24% were dissatisfied. Women reporting to be dissatisfied were significantly more likely to be sedentary, sick-listed, reporting poor eating habits and to be multiparous.

Conclusions: Most women reported to be satisfied with their maternal weight gain, but had gained excessively according to recommended weight gain ranges issued by IOM. Pregnant women may need targeted advice on their specific weight gain and impact of increased weight gain on health variables for mother and child.