Fetal weight Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2012;34(3):102-106
DOI 10.1590/S0100-72032012000300002
PURPOSE: To assess the prevalence of obstetric risk factors and their association with unfavorable outcomes for the mother and fetus. METHODS: A longitudinal, descriptive and analytical study was conducted on 204 pregnant women between May 2007 and December 2008. Clinical and laboratory assessments followed routine protocols. Risk factors included socio-demographic aspects; family, personal and obstetric history; high pre-gestational body mass index (BMI); excessive gestational weight gain and anemia. Adverse outcomes included pre-eclampsia (4.5%), gestational diabetes mellitus (3.4%), premature birth (4.4%), caesarian birth (40.1%), high birth weight (9.8%) and low birth weight (13.8%). RESULTS: The average age was 26±6.4 years; the mothers were predominantly non-white (84.8%), 51.8% had incomplete or complete secondary level schooling, 67.2% were in a stable marital relationship and 51.0% had a regular paid job; 63.7% were admitted to the prenatal clinic during the second trimester and 16.7% during the first, with 42.6% being primiparous. A past history of chronic hypertension was reported by 2.9%, pre-eclampsia by 9.8%, excessive gestational weight gain by 15.2% and former gestational diabetes mellitus by 1.0%. In the current pregnancy, elevated pre-gestational BMI was found in 34.6%; 45.5% presented with excessive gestational weight gain, 25.3% with anemia and 47.3% with dyslipidemia. Of the 17.5% of cases with altered blood glucose, gestational diabetes mellitus was confirmed in 3.4% and proteinuria occurred in 16.4% of all cases. Adverse maternal fetal outcomes included pre-eclampsia (4.5%), gestational diabetes mellitus (3.4%), premature birth (4.4%), caesarean birth (40.1%) and high and low birth weight (9.8% and 13.8%, respectively). Independent predictors of adverse maternal fetal outcomes were identified by Poisson multivariate regression analysis: pre-gestational BMI>25 kg/m² was a predictor for pre-eclampsia (RR=17.17; 95%CI 2.14-137.46) and caesarian operation (RR=1.79; 95%CI 1.13-2.85), previous caesarean was a predictor for present caesarean operation (RR=2.28; 95%CI 1.32-3.92) and anemia and high gestational weight gain were predictors for high birth weight (RR=3.38; 95%CI 1.41-8.14 and RR=4.68; 95%CI 1.56-14.01, respectively). CONCLUSION: Pre-gestational overweight/obesity, previous caesarean, excessive weight gain and anemia were major risk factors for pre-eclampsia, caesarean operations and high birth weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2012;34(3):102-106
DOI 10.1590/S0100-72032012000300002
PURPOSE: To assess the prevalence of obstetric risk factors and their association with unfavorable outcomes for the mother and fetus. METHODS: A longitudinal, descriptive and analytical study was conducted on 204 pregnant women between May 2007 and December 2008. Clinical and laboratory assessments followed routine protocols. Risk factors included socio-demographic aspects; family, personal and obstetric history; high pre-gestational body mass index (BMI); excessive gestational weight gain and anemia. Adverse outcomes included pre-eclampsia (4.5%), gestational diabetes mellitus (3.4%), premature birth (4.4%), caesarian birth (40.1%), high birth weight (9.8%) and low birth weight (13.8%). RESULTS: The average age was 26±6.4 years; the mothers were predominantly non-white (84.8%), 51.8% had incomplete or complete secondary level schooling, 67.2% were in a stable marital relationship and 51.0% had a regular paid job; 63.7% were admitted to the prenatal clinic during the second trimester and 16.7% during the first, with 42.6% being primiparous. A past history of chronic hypertension was reported by 2.9%, pre-eclampsia by 9.8%, excessive gestational weight gain by 15.2% and former gestational diabetes mellitus by 1.0%. In the current pregnancy, elevated pre-gestational BMI was found in 34.6%; 45.5% presented with excessive gestational weight gain, 25.3% with anemia and 47.3% with dyslipidemia. Of the 17.5% of cases with altered blood glucose, gestational diabetes mellitus was confirmed in 3.4% and proteinuria occurred in 16.4% of all cases. Adverse maternal fetal outcomes included pre-eclampsia (4.5%), gestational diabetes mellitus (3.4%), premature birth (4.4%), caesarean birth (40.1%) and high and low birth weight (9.8% and 13.8%, respectively). Independent predictors of adverse maternal fetal outcomes were identified by Poisson multivariate regression analysis: pre-gestational BMI>25 kg/m² was a predictor for pre-eclampsia (RR=17.17; 95%CI 2.14-137.46) and caesarian operation (RR=1.79; 95%CI 1.13-2.85), previous caesarean was a predictor for present caesarean operation (RR=2.28; 95%CI 1.32-3.92) and anemia and high gestational weight gain were predictors for high birth weight (RR=3.38; 95%CI 1.41-8.14 and RR=4.68; 95%CI 1.56-14.01, respectively). CONCLUSION: Pre-gestational overweight/obesity, previous caesarean, excessive weight gain and anemia were major risk factors for pre-eclampsia, caesarean operations and high birth weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2011;33(9):240-245
DOI 10.1590/S0100-72032011000900004
PURPOSE: To determine the accuracy of ultrasound in fetal weight estimation and to evaluate maternal and/or fetal factors that could interfere in the result. METHODS: This was a transverse prospective study, involving 106 patients, with 212 fetal weight evaluations, by two observers, within 24 h to delivery. The following parameters were measured: biparietal diameter, head circumference, abdominal circumference, and femoral length. Fetal weight was estimated using the Hadlock formula and the results were compared to birth weight. The maternal factors examined were: weight, BMI, and skin to uterus distance measured by ultrasound, and the fetal factors were: presentation, position, placental localization and thickness, fetal weight, and amniotic fluid index (AFI). RESULTS: There was good correlation between estimated fetal weight and birth weight (R=0.97). In 79.2% and in 92.4% of cases the estimated fetal weight was within 10% and 15% of birth weight, respectively. The only maternal factor that presented a positive correlation with percent error in the estimate of fetal weight was the skin to uterus distance (R³0.56). Fetal weight showed negative correlation with percent error (R>-0.36; p<0.001), with a significant tendency to overestimate fetal weight in the group of very low weight - <1000 g (p<0.05). The AFI showed a low negative correlation with percent error (R=-0.21; p<0.001) with no difference between AFI groups (p=0.516). CONCLUSION: Ultrasound presented good accuracy in the estimation of fetal weight. The error of weight estimate was directly proportional to the skin to uterus distance and inversely proportional to fetal weight. AFI did not interfere significantly in the ultrasound prediction of fetal weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2011;33(9):240-245
DOI 10.1590/S0100-72032011000900004
PURPOSE: To determine the accuracy of ultrasound in fetal weight estimation and to evaluate maternal and/or fetal factors that could interfere in the result. METHODS: This was a transverse prospective study, involving 106 patients, with 212 fetal weight evaluations, by two observers, within 24 h to delivery. The following parameters were measured: biparietal diameter, head circumference, abdominal circumference, and femoral length. Fetal weight was estimated using the Hadlock formula and the results were compared to birth weight. The maternal factors examined were: weight, BMI, and skin to uterus distance measured by ultrasound, and the fetal factors were: presentation, position, placental localization and thickness, fetal weight, and amniotic fluid index (AFI). RESULTS: There was good correlation between estimated fetal weight and birth weight (R=0.97). In 79.2% and in 92.4% of cases the estimated fetal weight was within 10% and 15% of birth weight, respectively. The only maternal factor that presented a positive correlation with percent error in the estimate of fetal weight was the skin to uterus distance (R³0.56). Fetal weight showed negative correlation with percent error (R>-0.36; p<0.001), with a significant tendency to overestimate fetal weight in the group of very low weight - <1000 g (p<0.05). The AFI showed a low negative correlation with percent error (R=-0.21; p<0.001) with no difference between AFI groups (p=0.516). CONCLUSION: Ultrasound presented good accuracy in the estimation of fetal weight. The error of weight estimate was directly proportional to the skin to uterus distance and inversely proportional to fetal weight. AFI did not interfere significantly in the ultrasound prediction of fetal weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(9):459-465
DOI 10.1590/S0100-72032008000900006
PURPOSE: to evaluate the effect of maternal, socioeconomic and obstetric variables, as well the presence of artery incisions in the 20th and 24th weeks on the fetal weight estimated at the end of pregnancy (36th week) in pregnant women attended by Programa Saúde da Família, in an inland town of the northeast of Brazil. METHODS: a longitudinal study including 137 pregnant women, who have been followed up every four weeks in order to assess clinical, socioeconomic and obstetric conditions, including their weight. The uterine arteries were evaluated by Doppler in the 20th and 24th weeks, the fetal weight and the amniotic fluid index (AFI), determined in the 36th week. The initial maternal nutritional state has been determined by the body mass index (BMI), the pregnant women being classified as low weight, eutrophic, over weight and obese. Weight gain during gestation has been evaluated, according to the initial nutritional state, being classified at the end of the second and third trimester as insufficient, adequate and excessive weight gain. Analysis of variance was performed to evaluate the association of the fetal weight in the 36th week with the predictor variables, adjusted by multiple linear regression. RESULTS: an association between the fetal weight estimated in the 36th week and the mother's age (p=0.02), mother's job (p=0.02), initial nutritional state (p=0.04), weight gain in the second trimester (p=0.01), presence of incisions in the uterine arteries (p=0.02), and AFI (p=0.007) has been observed. The main factors associated to the fetal weight estimated in the 36th week, after the multiple regression analysis were: BMI at the pregnancy onset, weight gain in the second trimester, AFI and tabagism. CONCLUSIONS: in the present study, the fetal weight is positively associated with the initial maternal nutritional state, the weight gain in the second trimester and the volume of amniotic fluid, and negatively, to tabagism.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2008;30(9):459-465
DOI 10.1590/S0100-72032008000900006
PURPOSE: to evaluate the effect of maternal, socioeconomic and obstetric variables, as well the presence of artery incisions in the 20th and 24th weeks on the fetal weight estimated at the end of pregnancy (36th week) in pregnant women attended by Programa Saúde da Família, in an inland town of the northeast of Brazil. METHODS: a longitudinal study including 137 pregnant women, who have been followed up every four weeks in order to assess clinical, socioeconomic and obstetric conditions, including their weight. The uterine arteries were evaluated by Doppler in the 20th and 24th weeks, the fetal weight and the amniotic fluid index (AFI), determined in the 36th week. The initial maternal nutritional state has been determined by the body mass index (BMI), the pregnant women being classified as low weight, eutrophic, over weight and obese. Weight gain during gestation has been evaluated, according to the initial nutritional state, being classified at the end of the second and third trimester as insufficient, adequate and excessive weight gain. Analysis of variance was performed to evaluate the association of the fetal weight in the 36th week with the predictor variables, adjusted by multiple linear regression. RESULTS: an association between the fetal weight estimated in the 36th week and the mother's age (p=0.02), mother's job (p=0.02), initial nutritional state (p=0.04), weight gain in the second trimester (p=0.01), presence of incisions in the uterine arteries (p=0.02), and AFI (p=0.007) has been observed. The main factors associated to the fetal weight estimated in the 36th week, after the multiple regression analysis were: BMI at the pregnancy onset, weight gain in the second trimester, AFI and tabagism. CONCLUSIONS: in the present study, the fetal weight is positively associated with the initial maternal nutritional state, the weight gain in the second trimester and the volume of amniotic fluid, and negatively, to tabagism.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1998;20(1):25-32
DOI 10.1590/S0100-72031998000100005
It is universally accepted that prenatal care has a beneficial impact on perinatal outcome. However, it is unclear whether access to early and frequent prenatal care influences the impact of pregnancy complications on birth weight. The objective of the present study was to determine the effectiveness of prenatal care, concerning antenatal visits (number and time of the first one), on gestational age and fetal weight at birth. We assessed prospectively the effect of the antenatal care in a group of 648 infants born consecutively at the University Hospital of Santa Maria, weighing from <1000 to >4000 g, and from <28 to >40 weeks of gestational age. Preterm delivery (<37 weeks) accounted for 17.7% of all deliveries, low birth-weight infants (<2500 g) for 20.5%, and very low birth-weight infants (<1000 g) for 2.8%. When the first antenatal visit was performed before the 12th week, only 5.1% of the babies were born with <37 weeks of gestational age or weight at birth of <2500 g. However, when the first visit was after the 28th week, the percentage of preterm delivery was 41.3% and of birth weight <2500 g was 43.5%. A significant association between higher frequency of antenatal visits, early care and decrease in preterm delivery frequency and low birth-weight infants was noted (p <0.001). We conclude that increase in the number of antenatal visits and early care can reduce the preterm delivery and low-birth weight infant rates.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1998;20(1):25-32
DOI 10.1590/S0100-72031998000100005
It is universally accepted that prenatal care has a beneficial impact on perinatal outcome. However, it is unclear whether access to early and frequent prenatal care influences the impact of pregnancy complications on birth weight. The objective of the present study was to determine the effectiveness of prenatal care, concerning antenatal visits (number and time of the first one), on gestational age and fetal weight at birth. We assessed prospectively the effect of the antenatal care in a group of 648 infants born consecutively at the University Hospital of Santa Maria, weighing from <1000 to >4000 g, and from <28 to >40 weeks of gestational age. Preterm delivery (<37 weeks) accounted for 17.7% of all deliveries, low birth-weight infants (<2500 g) for 20.5%, and very low birth-weight infants (<1000 g) for 2.8%. When the first antenatal visit was performed before the 12th week, only 5.1% of the babies were born with <37 weeks of gestational age or weight at birth of <2500 g. However, when the first visit was after the 28th week, the percentage of preterm delivery was 41.3% and of birth weight <2500 g was 43.5%. A significant association between higher frequency of antenatal visits, early care and decrease in preterm delivery frequency and low birth-weight infants was noted (p <0.001). We conclude that increase in the number of antenatal visits and early care can reduce the preterm delivery and low-birth weight infant rates.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1998;20(10):551-555
DOI 10.1590/S0100-72031998001000002
Purpose: to assess the validity of fetal weight estimation by a method based on uterine height -- Johnson's rule. Methods: one hundred and one pregnant women and their newborn children were studied. The fetal weight was estimated using an adaptation of Johnson's rule, which consists of the clinical application of a mathematical model to calculate the fetal weight based on the uterine height and the height of fetal presentation. The estimated weight was obtained on the day of delivery and was compared to the weight observed after birth. This, in turn, was the control of the analysis of validity of the method used. On the same date, a detailed obstetrical ultrasonography (US) was conducted which included the fetal weight, calculated by the use of Sheppard's tables. This weight, estimated by US, was compared to the birth weight. Results: the results have proven that the clinical estimate used in this study has a similar value to that of the US calculation of birth weight. The accuracy of the clinical method, with variations of 5%, 10% and 15% between estimated and observed weights, was 55.3%, 73% and 86.7%, respectively. Those of the US were 60.7%, 75.4% and 91.1%, respectively. When comparing both sets of figures, values were not different from a statistical standpoint. Conclusion: the clinical evaluation has shown to be accurate, similarly to the US, when calculating the birth weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 1998;20(10):551-555
DOI 10.1590/S0100-72031998001000002
Purpose: to assess the validity of fetal weight estimation by a method based on uterine height -- Johnson's rule. Methods: one hundred and one pregnant women and their newborn children were studied. The fetal weight was estimated using an adaptation of Johnson's rule, which consists of the clinical application of a mathematical model to calculate the fetal weight based on the uterine height and the height of fetal presentation. The estimated weight was obtained on the day of delivery and was compared to the weight observed after birth. This, in turn, was the control of the analysis of validity of the method used. On the same date, a detailed obstetrical ultrasonography (US) was conducted which included the fetal weight, calculated by the use of Sheppard's tables. This weight, estimated by US, was compared to the birth weight. Results: the results have proven that the clinical estimate used in this study has a similar value to that of the US calculation of birth weight. The accuracy of the clinical method, with variations of 5%, 10% and 15% between estimated and observed weights, was 55.3%, 73% and 86.7%, respectively. Those of the US were 60.7%, 75.4% and 91.1%, respectively. When comparing both sets of figures, values were not different from a statistical standpoint. Conclusion: the clinical evaluation has shown to be accurate, similarly to the US, when calculating the birth weight.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2000;22(1):19-26
DOI 10.1590/S0100-72032000000100004
Purpose: to evaluate gestational and delivery complications as risk factors for perinatal death. Methodology - Patients: the cases (perinatal deaths) were identified among a total of 3,031 deliveries from the maternity of the Rio de Janeiro State Military Police. Methods: the study design was a nested case-control one. Cases (n = 82) were perinatal deaths with a minimum gestational age of 28 weeks or a weight of 1,000 g. Controls (n = 246) were live babies for the first week of life. The analysis was made in three steps: univariate, stratified and multivariate (logistic regression). Results: the gestational complications showed an odds ratio of 4.21 and the delivery complications, 5.26. The newborn weight showed an OR = 0.999 per gram over 1,000 g weight. The gestational age showed an OR = 0.729 per week of gestation over 28 weeks. Conclusions: the gestational complications and the delivery complications were important risk factors for perinatal death. The gestational age and the weight of the newborn were important protective factors.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2000;22(1):19-26
DOI 10.1590/S0100-72032000000100004
Purpose: to evaluate gestational and delivery complications as risk factors for perinatal death. Methodology - Patients: the cases (perinatal deaths) were identified among a total of 3,031 deliveries from the maternity of the Rio de Janeiro State Military Police. Methods: the study design was a nested case-control one. Cases (n = 82) were perinatal deaths with a minimum gestational age of 28 weeks or a weight of 1,000 g. Controls (n = 246) were live babies for the first week of life. The analysis was made in three steps: univariate, stratified and multivariate (logistic regression). Results: the gestational complications showed an odds ratio of 4.21 and the delivery complications, 5.26. The newborn weight showed an OR = 0.999 per gram over 1,000 g weight. The gestational age showed an OR = 0.729 per week of gestation over 28 weeks. Conclusions: the gestational complications and the delivery complications were important risk factors for perinatal death. The gestational age and the weight of the newborn were important protective factors.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2004;26(9):691-695
DOI 10.1590/S0100-72032004000900003
PURPOSE: to evaluate the importance of circulating maternal and fetal leptin in the healthy gestation, using its association with maternal, placental and fetal anthropometric variables, obtained at birth, and the relationship between the evaluated compartments. METHODS: in a transversal study a population of 33 single, healthy and term gestations was studied. The evaluated variables were maternal age, maternal weight, body mass index (BMF), weight of the newborn, placental weight, and placental index. Samples of maternal blood were immediately obtained before birth and from fetal umbilical cord blood at birth. Determination of serum leptin was performed using conventional radioimmunoassay. The relationships between serum leptin concentrations in maternal blood, umbilical artery and vein and the studied variables were assessed through linear regression. RESULTS: leptin levels were detected in the blood of all 33 pregnant women and their respective newborns, with maternal blood concentration (17.1±1.77 ng/mL) higher than that of umbilical vessels (vein: 9.0±1.16 ng/mL; artery: 8.23±1.02 ng/mL), p<0.0001. Leptin concentrations in the maternal blood were correlated with leptin concentrations in fetal blood (artery: coef. 0.63, p=0.037; vein: coef. 0.72, p=0.006). Regarding the anthropometric variables, leptin measured in the maternal blood was associated with initial and final maternal BMF (coef. 1.13; p=0.002; coef. 1,18, p=0.001) and cord leptin levels were correlated with the fetal weight at birth (vein: coef. 0.007, p=0.02; artery: coef. 0.006, p=0.02). CONCLUSION: there was a correlation between maternal and fetal leptin production and probably by the action of similar stimuli during gestation. Serum leptin was associated with the weight of the compartment where it circulates.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2004;26(9):691-695
DOI 10.1590/S0100-72032004000900003
PURPOSE: to evaluate the importance of circulating maternal and fetal leptin in the healthy gestation, using its association with maternal, placental and fetal anthropometric variables, obtained at birth, and the relationship between the evaluated compartments. METHODS: in a transversal study a population of 33 single, healthy and term gestations was studied. The evaluated variables were maternal age, maternal weight, body mass index (BMF), weight of the newborn, placental weight, and placental index. Samples of maternal blood were immediately obtained before birth and from fetal umbilical cord blood at birth. Determination of serum leptin was performed using conventional radioimmunoassay. The relationships between serum leptin concentrations in maternal blood, umbilical artery and vein and the studied variables were assessed through linear regression. RESULTS: leptin levels were detected in the blood of all 33 pregnant women and their respective newborns, with maternal blood concentration (17.1±1.77 ng/mL) higher than that of umbilical vessels (vein: 9.0±1.16 ng/mL; artery: 8.23±1.02 ng/mL), p<0.0001. Leptin concentrations in the maternal blood were correlated with leptin concentrations in fetal blood (artery: coef. 0.63, p=0.037; vein: coef. 0.72, p=0.006). Regarding the anthropometric variables, leptin measured in the maternal blood was associated with initial and final maternal BMF (coef. 1.13; p=0.002; coef. 1,18, p=0.001) and cord leptin levels were correlated with the fetal weight at birth (vein: coef. 0.007, p=0.02; artery: coef. 0.006, p=0.02). CONCLUSION: there was a correlation between maternal and fetal leptin production and probably by the action of similar stimuli during gestation. Serum leptin was associated with the weight of the compartment where it circulates.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2001;23(2):113-117
DOI 10.1590/S0100-72032001000200009
Purpose: to examine the effects of tramadol hydrochloride on rat pregnancy. Methods: five groups of 10 pregnant albino rats each were treated from the 1st up to the 20th day of pregnancy as follows: GI = intact controls; GII = controls which received 0.5 ml of distilled water (drug vehicle) once a day by gavage; GIII, GIV and GV = groups treated respectively with 6.7, 20.1 or 45.6 mg/kg of tramadol hydrochloride once a day by gavage in a final volume of 0.5 mL. Body weight gain was monitored by weighing at the beginning and on the 7th, 14th and 20th day of pregnancy. At term the animals were killed under deep ether anesthesia and the following parameters were evaluated: number of implantations, of resorptions, of viable fetuses and of placentae; presence of major malformations; maternal and fetal mortality and weights of fetuses and placentae. Results: tramadol significantly affected maternal body weight gain, this effect being more apparent in groups IV and V (mean reductions of weight gain of 41 and 56%, respectively). In group III the weight gain was affected more at days 7 and 14 (33% mean gain reductions) than at day 20 (19%). Drug treatment affected significantly and in a dose-dependent fashion the following parameters: individual weight of fetuses (GV = -39.2%), offspring weight (GIV = -51.7%; GV = -44.2%), number of placentae (GIV = -28.4%; GV = -11.6%), individual weight of placentae (GV = -10%) and the total weight of placentae (GIV = -28.4%; GV = -16.8%). Though among the treated animals there was an increase in resorptions and deaths at birth, these events were not significantly different from those found in controls. Conclusions: Tramadol showed definite deleterious effects on albino rat pregnancy, and these effects were exerted not only on the maternal but also the on fetal organisms. Overall, the effects were more pronounced at the 14th than at the 20th day of pregnancy, thus suggesting that the organogenic phase of the fetus is more susceptible than its initial (embryogenic) or final (term) phases. The results call attention to the care which is to be taken when the use of this opioid is considered during pregnancy.
Summary
Revista Brasileira de Ginecologia e Obstetrícia. 2001;23(2):113-117
DOI 10.1590/S0100-72032001000200009
Purpose: to examine the effects of tramadol hydrochloride on rat pregnancy. Methods: five groups of 10 pregnant albino rats each were treated from the 1st up to the 20th day of pregnancy as follows: GI = intact controls; GII = controls which received 0.5 ml of distilled water (drug vehicle) once a day by gavage; GIII, GIV and GV = groups treated respectively with 6.7, 20.1 or 45.6 mg/kg of tramadol hydrochloride once a day by gavage in a final volume of 0.5 mL. Body weight gain was monitored by weighing at the beginning and on the 7th, 14th and 20th day of pregnancy. At term the animals were killed under deep ether anesthesia and the following parameters were evaluated: number of implantations, of resorptions, of viable fetuses and of placentae; presence of major malformations; maternal and fetal mortality and weights of fetuses and placentae. Results: tramadol significantly affected maternal body weight gain, this effect being more apparent in groups IV and V (mean reductions of weight gain of 41 and 56%, respectively). In group III the weight gain was affected more at days 7 and 14 (33% mean gain reductions) than at day 20 (19%). Drug treatment affected significantly and in a dose-dependent fashion the following parameters: individual weight of fetuses (GV = -39.2%), offspring weight (GIV = -51.7%; GV = -44.2%), number of placentae (GIV = -28.4%; GV = -11.6%), individual weight of placentae (GV = -10%) and the total weight of placentae (GIV = -28.4%; GV = -16.8%). Though among the treated animals there was an increase in resorptions and deaths at birth, these events were not significantly different from those found in controls. Conclusions: Tramadol showed definite deleterious effects on albino rat pregnancy, and these effects were exerted not only on the maternal but also the on fetal organisms. Overall, the effects were more pronounced at the 14th than at the 20th day of pregnancy, thus suggesting that the organogenic phase of the fetus is more susceptible than its initial (embryogenic) or final (term) phases. The results call attention to the care which is to be taken when the use of this opioid is considered during pregnancy.
