Verbênia Nunes Costa

Influência do estado nutricional materno, ganho de peso e consumo energético sobre o crescimento fetal, em gestações de alto risco

PURPOSE To analyze the influence of maternal nutritional status, weight gain and energy consumption on fetal growth in high-risk pregnancies. METHODS A prospective study from August 2009 to August 2010 with the following inclusion criteria: puerperae up to the 5th postpartum day; high-risk singleton pregnancies (characterized by medical or obstetrical complications during pregnancy); live fetus at labor onset; delivery at the institution; maternal weight measured on the day of delivery, and presence of medical and/or obstetrical complications characterizing pregnancy as high-risk. Nutritional status was assessed by pregestational body mass index and body mass index in late pregnancy, and the patients were classified as: underweight, adequate, overweight and obese. A food frequency questionnaire was applied to evaluate energy consumption. We investigated maternal weight gain, delivery data and perinatal outcomes, as well as fetal growth based on the occurrence of small for gestational age and large for gestational age neonates. RESULTS We included 374 women who were divided into three study groups according to newborn birth weight: adequate for gestational age (270 cases, 72.2%), small for gestational age (91 cases, 24.3%), and large for gestational age (13 cases, 3.5%). Univaried analysis showed that women with small for gestational age neonates had a significantly lower mean pregestational body mass index (23.5 kg/m², p<0.001), mean index during late pregnancy (27.7 kg/m², p<0.001), and a higher proportion of maternal underweight at the end of pregnancy (25.3%, p<0.001). Women with large for gestational age neonates had a significantly higher mean pregestational body mass index (29.1 kg/m², p<0.001), mean index during late pregnancy (34.3 kg/m², p<0.001), and a higher proportion of overweight (30.8%, p=0.02) and obesity (38.5%, p=0.02) according to pregestational body mass index, and obesity at the end of pregnancy (53.8%, p<0.001). Multivariate analysis revealed the index value during late pregnancy (OR=0.9; CI95% 0.8-0.9, p<0.001) and the presence of hypertension (OR=2.6; 95%CI 1.5-4.5, p<0.001) as independent factors for small for gestational age. Independent predictors of large for gestational age infant were the presence of diabetes mellitus (OR=20.2; 95%CI 5.3-76.8, p<0.001) and obesity according to body mass index during late pregnancy (OR=3.6; 95%CI 1.1-11.7, p=0.04). CONCLUSION The maternal nutritional status at the end of pregnancy in high-risk pregnancies is independently associated with fetal growth, the body mass index during late pregnancy is a protective factor against small for gestational age neonates, and maternal obesity is a risk factor for large for gestational age neonates.

Cardiac troponin T as a biochemical marker of cardiac dysfunction and ductus venosus Doppler velocimetry

OBJECTIVES The aim of this study was to determine the correlation between ductus venosus (DV) Doppler velocimetry and fetal cardiac troponin T (cTnT). STUDY DESIGN Between March 2007 and March 2008, 89 high-risk pregnancies were prospectively studied. All patients delivered by cesarean section and the Doppler exams were performed on the same day. Multiple regression included the following variables: maternal age, parity, hypertension, diabetes, gestational age at delivery, umbilical artery (UA) S/D ratio, diagnosis of absent or reversed end-diastolic flow velocity (AREDV) in the UA, middle cerebral artery (MCA) pulsatility index (PI), and DV pulsatility index for veins (PIV). Immediately after delivery, UA blood samples were obtained for the measurement of pH and cTnT levels. Statistical analysis included the Kruskal-Wallis test and multiple regressions. RESULTS The results showed a cTnT concentration at birth >0.05 ng/ml in nine (81.8%) of AREDV cases, a proportion significantly higher than that observed in normal UA S/D ratio and UA S/D ratio >p95 with positive diastolic blood flow (7.7 and 23.1%, respectively, p<0.001). A positive correlation was found between abnormal DV-PIV and elevated cTnT levels in the UA. Multiple regression identified DV-PIV and a diagnosis of AREDV as independent factors associated with abnormal fetal cTnT levels (p<0.0001, F(2.86)=63.5, R=0.7722). CONCLUSION DV-PIV was significantly correlated with fetal cTnT concentrations at delivery. AREDV and abnormal DV flow represent severe cardiac compromise, with increased systemic venous pressure, and a rise in right ventricular afterload, demonstrated by myocardial damage and elevated fetal cTnT.

Correlation between the Doppler velocimetry findings of the uterine arteries during the first and second trimesters of pregnancy

OBJECTIVES Evaluate the feasibility of transvaginal uterine artery Doppler examination in the first and second trimesters of pregnancy, establish reference ranges in a Brazilian population and examine the correlation between these Doppler findings. METHODS Longitudinal prospective study at the antenatal clinic of a tertiary teaching hospital. Uterine artery Doppler examinations were carried out transvaginally at 11 to 14 weeks and 20 to 25 weeks of gestation. Uterine artery mean pulsatility index (PI) distributions were determined and the presence or absence of an early diastolic notch was also noted. The degree of correlation between first and second trimester Doppler findings was examined. RESULTS Three hundred and forty four women with live singleton pregnancies and normal outcome were first examined at a mean gestation of 12.7 weeks. The values corresponding to the 50th and 95th centiles of mean PI were 1.69 and 2.48. Bilateral notches were observed in 44% of cases and unilateral notches were present in 19%. Second trimester Doppler examinations were carried out at a mean gestation of 23.2 weeks and corresponding figures for the 50th and 95th centiles were 1.03 and 1.57. Bilateral notches were noted in 4.4% of the cases. First trimester impedance indices were significantly higher and positively correlated to second trimester findings (r = 0.42, p<0.0001). CONCLUSION Uterine artery Doppler examination can be successfully performed transvaginally and incorporated into scans that are routinely offered to women during their antenatal care in the first and second trimesters. Doppler indices obtained during the first trimester are significantly higher than those of the second trimester and findings at both scans are significantly correlated.

Fetal venous Doppler in pregnancies with placental dysfunction and correlation with pH at birth

Objectives: To determine the correlation between ph at birth and venous Doppler parameters in pregnancies with placental dysfunction. Methods: This was a prospective cohort study of 58 pregnancies with the diagnosis of placental dysfunction between 26 and 34 weeks of gestation. Inclusion criteria were singleton pregnancies, abnormal umbilical artery (UA) Doppler, fetal growth restriction diagnosed by estimated fetal weight <10th centile for gestational age, intact membranes, and absence of fetal congenital abnormalities. The Doppler measurements were the following: UA pulsatility index (PI), ductus venosus (DV) pulsatility index for veins (PIV), intra-abdominal umbilical vein (UV) time-averaged maximum velocity (TAMxV) and blood flow and left portal vein (LPV) time-averaged maximum velocity (TAMxV) and blood flow. All Doppler parameters were transformed into z-scores (SD values from the mean) according to normative references. Results: The UA pH at birth showed a negative significant correlation with the DV-PIV (p = 0.004) and the DV-PIV z-score (p = 0.004), while LPV TAMxV (p = 0.004), LPV TAMxV z-score (p = 0.002), LPV blood flow (p = 0.01), LPV blood flow normalized (p = 0.04) and UV blood flow (p = 0.04) positively correlated with pH at birth. Multiple regression analysis was performed and the DV-PIV z-score was the variable that independently correlated with pH at birth (p = 0.002). Conclusions: the present results suggest that changes in fetal venous blood flow, mainly DV and LPV are useful in the management of cases with early onset placental insufficiency and that venous Doppler parameters correlate with pH at birth.

Effects of maternal glycemia on fetal heart rate in pregnancies complicated by pregestational diabetes mellitus.

OBJECTIVE To investigate the influence of maternal glycemia on fetal heart rate (FHR) parameters analyzed by computerized cardiotocography in fetuses of diabetic mothers in the third trimester. STUDY DESIGN Thirty-nine pregnant women with pregestational diabetes mellitus were studied prospectively. The inclusion criteria were a diagnosis of pregestational diabetes, singleton pregnancy between 36 and 40 weeks, and absence of fetal abnormalities. Computerized cardiotocography (System 8002) was performed over a period of 60 min and capillary glycemia was measured immediately before and 30 and 60 min after the beginning of the exam. The evaluations were done 2 h after lunch. RESULTS Nineteen patients (48.7%) presented mean glycemia > or =120 mg/dL. The mean basal FHR was 136.7+/-10.0 bpm in the group with glycemia <120 mg/dL and 144.8+/-9.4 bpm in the group with glycemia > or =120 mg/dL (p=0.013, Students t test). There was a significant positive correlation (Pearsons test, p=0.0001, r=0.57) between basal FHR and mean glycemia. A significant negative correlation was observed between short-term variation and mean glycemia (Pearsons test, p=0.003, r=-0.47). No significant differences were observed between the other indices evaluated by computerized cardiotocography and glycemia. CONCLUSIONS Maternal hyperglycemia at the time of cardiotocography is associated with elevated FHR. It seems to be important to understand how FHR parameters are influenced by maternal glycemic status at the time of fetal assessment in pregnancies complicated by diabetes.

Cardiotocografia computadorizada em gestações complicadas pelo diabete melito pré-gestacional: padrões da freqüência cardíaca em fetos grandes para a idade gestacional

OBJETIVO: verificar os padroes da frequencia cardiaca de fetos grandes para a idade gestacional (GIG), em gestantes com diabete melito pre-gestacional. METODOS: sessenta e quatro gestantes diabeticas pre-gestacionais foram avaliadas semanalmente quanto a vitalidade fetal. Os criterios de inclusao foram: diagnostico pre-gestacional de diabetes melito, gestacao unica, feto vivo, ausencia de anomalia fetal e cardiotocografia computadorizada realizada na 37a semana. Os criterios de exclusao foram: diagnostico pos-natal de anomalia fetal e parto nao realizado na instituicao. Os padroes da frequencia cardiaca fetal (FCF) foram investigados pela cardiotocografia computadorizada (Sistema-8002 Sonicaid). Os parâmetros foram analisados de acordo com a classificacao pela adequacao do peso do recem-nascido em GIG (acima do percentil 90 para a idade gestacional). Os parâmetros cardiotocograficos incluiram: FCF basal, aceleracoes, episodios de alta variacao, episodios de baixa variacao e variacao de curto prazo. RESULTADOS: do total, 42 pacientes preencheram os criterios propostos. Houve 10 recem-nascidos GIG (23,8%). A cardiotocografia apresentou resultado normal em todos os casos. As aceleracoes da FCF (superiores a 15 bpm) estavam presentes em 7 (70%) dos casos GIG e em 29 (90,6%) dos casos nao GIG (p=0,135). A frequencia dessas aceleracoes foi maior no grupo nao GIG (1,5±1,3 aceleracoes/10 min) quando comparado ao grupo GIG (0,8±0,9 aceleracoes/10 min, p=0,04, teste de Mann-Whitney). Os episodios de alta variacao foram detectados em todos os casos. A media da variacao nesses episodios foi diferente no grupo GIG (16,2±2,5 bpm) quando comparado ao nao GIG (19,7±4,2 bpm, p=0,02, teste de Mann-Whitney). CONCLUSOES: os padroes da FCF verificados em fetos nao GIG (maior frequencia de aceleracoes e a maior variacao da FCF em episodios de alta variacao) refletem parâmetros comumente analisados pela cardiotocografia tradicional na higidez fetal. Esse fato sugere a existencia de padroes indicativos de melhor condicao de oxigenacao dos fetos menos comprometidos pelos efeitos do diabetes na gravidez.

Avaliação da vitalidade fetal em gestações complicadas pela plaquetopenia materna moderada ou grave

PURPOSE To analyze the results of assessment of fetal well-being in pregnancies complicated by moderate or severe maternal thrombocytopenia. METHODS Data from April 2001 to July 2011 of 96 women with a diagnosis of thrombocytopenia in pregnancy were retrospectively analyzed. We analyzed the following tests performed during the antepartum period for fetal assessment: cardiotocography, fetal biophysical profile, amniotic fluid index and umbilical artery Doppler velocimetry. RESULTS A total of 96 pregnancies with the following diagnoses were analyzed: gestational thrombocytopenia (n=37, 38.5%) hypersplenism (n=32, 33.3%), immune thrombocytopenic purpura (ITP, n=14, 14.6%), secondary immune thrombocytopenia (n=6, 6.3%), bone marrow aplasia (n=3, 3.1%), and others (n=4, 4.1%). Cardiotocography showed normal results in 94% of cases, a fetal biophysical profile with an index of 8 or 10 in 96.9% and an amniotic fluid index >5.0 cm in 89.6%. Doppler umbilical artery velocimetry showed normal results in 96.9% of cases. In the analysis of the major groups of thrombocytopenia, the diagnosis of oligohydramnios was found to be significantly more frequent in the group with ITP (28.6%) compared to the other groups (gestational thrombocytopenia: 5.4% and hypersplenism: 9.4%, p=0.04). CONCLUSIONS This study indicates that in pregnancies complicated by moderate or severe maternal thrombocytopenia, even though the fetal well-being remains preserved in most cases, fetal surveillance is important in pregnant women with ITP, with emphasis on amniotic fluid volume evaluation due to its association with oligohydramnios.

Cord blood B-type natriuretic peptide levels in placental insufficiency: correlation with fetal Doppler and pH at birth

OBJECTIVE To examine the correlation of cardiac B-type natriuretic peptide (BNP) concentrations in umbilical cord blood at birth with fetal Doppler parameters and pH at birth. STUDY DESIGN Prospective cross-sectional study with the following inclusion criteria: women with a singleton pregnancy, placental insufficiency characterized by increased pulsatility index (PI) of the umbilical artery (UA), intact membranes, and absence of fetal abnormalities. The exclusion criteria kept out cases of newborns with postnatal diagnosis of abnormality and cases in which the blood analysis was not performed. The Doppler parameters used were the UA PI, middle cerebral artery (MCA) PI, cerebroplacental ratio (CPR), and ductus venosus (DV) PI for veins (PIV), all converted into zeta scores. Blood samples were obtained from the umbilical cord immediately after delivery to measure the pH of the UA and the BNP. RESULTS Thirty-two pregnancies with placental insufficiency were included, 21 (65%) with positive diastolic flow and 11 (35%) with absent or reversed end diastolic flow in the UA. The concentration of BNP correlated significantly with the UA PI z-score (rho=0.43, P=0.016), the CPR z-score (rho=-0.35, P=0.048), the DV PIV z-score (rho=0.61, P<0.001), pH at birth (rho=-0.39, P=0.031), and gestational age (rho=-0.51, P=0.003). In the multiple regression analysis, antenatal parameters were included; the DV PIV z-score (P=0.008) was found to be an independent parameter correlating with BNP at birth. Correlation between BNP and the DV PIV z-score was borne out by the regression equation Log[BNP]=2.34+0.13*DV (F=18.8, P<0.001). Correlation between BNP and pH at birth was confirmed by the regression equation Log[BNP]=21.36-2.62*pH (F=7.69, P=0.01). CONCLUSION The results suggest that fetal cardiac dysfunction identified by BNP concentrations at birth correlated independently with changes in DV PIV and correlated negatively with pH values at birth.