Body composition during normal pregnancy: reference ranges.

Maternal body composition undergoes a deep adaptative change during the course of pregnancy. Fat mass, fat-free mass, and total body water (TBW) increase in different ways and their effects on pregnancy outcome represent a field of major interest in perinatal medicine. The aim of this study was to evaluate the changes in maternal body composition [maternal weight, TBW, intracellular water (ICW) and extracellular water (ECW)] during healthy pregnancy by using bioimpedance analysis (BIA). A total of 170 healthy pregnant women, aged 22-44 years, volunteered to participate in our study. The BIA measurements were carried out with a Tefal BIA scale determining resistance and reactance. Lukaski's multiple-regression equation was used to estimate TBW and ICW and ECW were computed using the prediction formula of Segal. The evaluations were performed at 10-38 weeks' gestation, every 3-4 weeks, and hematocrit was determined at every time interval. Analysis of variance and multiple comparisons of Bonferroni were performed to compare variables among the different study intervals. Second-order polynomial interpolation was used to obtain percentile values for each bioimpedance parameter. Percentile bioimpedance values of the healthy population are provided at each study time, by showing the mean value and the 5th, 25th, 75th, 95th percentiles. Moreover, normal reference ranges for TBW are provided for each gestational age, in relation to maternal weight gain. Reactance, TBW, and ICW enhance slightly during the course of gestation. Tetrapolar BIA could be an easy and practical tool for evaluating changes of maternal body components during pregnancy. It could also provide indirect proof of the normal hemodilution occurring in normal pregnancies. Moreover, fat mass deposition, and not only fluid retention, seems to be responsible for the mother's gestational weight gain, since reactance is an indirect parameter in estimating fat mass amount.

Intrauterine growth restriction and fetal body composition.

OBJECTIVE: To assess the differences in fetal body compartments between fetuses with normal growth and those with reduced intrauterine growth, during the third trimester, through ultrasonographic determination of subcutaneous tissue thickness (SCTT). METHODS: Twenty-eight patients were enrolled into this case control study carried out at 30-31 weeks' gestation. Two study groups were matched for maternal age and pregestational body mass index: controls (n = 14) and intrauterine growth-restricted (IUGR) fetuses (n = 14). Routine ultrasound-derived biometric parameters (head circumference, abdominal circumference, femur length and humerus length) were measured. Additionally, the mid-arm fat mass and lean mass (MAFM and MALM), the mid-thigh fat mass and lean mass (MTFM and MTLM), the abdominal fat mass (AFM) and the subscapular fat mass (SSFM) were measured. The Mann-Whitney U-test and Student's t-test were used to compare the two groups. RESULTS: The abdominal circumference and the humerus were significantly smaller in IUGR fetuses than in controls. Most of the SCTT values were different in the two groups. The SSFM (3.6 +/- 1.1 vs. 2.6 +/- 0.7 mm; P = 0.011), the AFM (5.1 +/- 0.7 vs. 4 +/- 1 mm; P = 0.01), the MAFM (3.5 +/- 0.9 vs. 2.2 +/- 0.8 cm2; P < 0.01) and MALM (2.1 +/- 0.4 vs. 1.7 +/- 0.5 cm2; P = 0.029) were all significantly greater in fetuses with normal development compared to those with growth restriction. CONCLUSIONS: During the third trimester, SCTT (with the exception of MTFM and MTLM) is reduced in fetuses with IUGR. Furthermore, MALM is lower in growth-restricted fetuses, confirming that the parameters measured in this study are affected in IUGR fetuses. Our findings indicate that specific changes in fetal body compartments occur as a result of chronic metabolic impairment.

Abnormal maternal cardiac function and morphology in pregnancies complicated by intrauterine fetal growth restriction.

OBJECTIVE: To explore maternal cardiac function through an echocardiographic evaluation, in a group of nulliparous patients with intrauterine fetal growth restriction during the third trimester of pregnancy. METHODS: Twenty-one consecutive nulliparous pregnant women who had fetuses with intrauterine growth restriction (IUGR) and abnormal umbilical artery Doppler pulsatility index (PI) underwent maternal echocardiographic examination during the third trimester of gestation. The data were then compared with those obtained from 21 normal nulliparous women who had fetuses with an estimated fetal weight > 10th percentile and a normal umbilical artery Doppler PI who were considered as the control group. RESULTS: Heart rate was slightly lower in the IUGR group, whereas blood pressure and total vascular resistance were higher compared with the control subjects. End-diastolic volume, stroke volume and cardiac output were lower in the IUGR patients compared with normal patients. The IUGR group had smaller left atrial maximal dimensions and greater left atrial minimal areas compared with the control subjects. Left atrial function was depressed in the IUGR group. A smaller left ventricular mass was present in the IUGR patients compared with the control subjects. Isovolumetric relaxation time (IVRT) was prolonged in the IUGR patients compared with the controls. CONCLUSIONS: The absence of a 'correct' maternal cardiovascular compensatory response to abnormal trophoblastic invasion, might be one of the factors that slowly determine the conditions of reduced placental perfusion and eventually of the development of fetal growth restriction.

Isolation of MUC1-primed B lymphocytes from tumour-draining lymph nodes by immunomagnetic beads.

The humoral immune response against a tumour-associated antigen, polymorphic epithelial mucin (PEM, MUC1) in cancer patients was studied by isolating specific B cells primed for the antigen. Human B lymphocytes from tumour-draining lymph nodes, obtained from 12 patients with epithelial cancers, were immunoselected with magnetic beads coated with a 60mer synthetic peptide corresponding to three tandem repeats of the protein core of the MUC1 antigen. Short-term cultures of B cells were established utilizing interleukin-10 (IL-10), IL-4 and monoclonal antibody anti-CD40, and were maintained for a maximum of 3 weeks. B cell culture supernatants contained human anti-MUC1 antibodies, as detected by enzyme-linked immunosorbent assay, in 6/12 of the patients tested. Five of these patients, all with early-stage cancer, also had high levels of circulating anti-MUC1 IgM antibodies in the serum. A significant correlation was found (two-tailed P = 0.041) between the presence of circulating anti-MUC1 antibodies and the ability to isolate PEM-specific B cells from tumour-draining lymph nodes. The technique proposed provides a useful method for the analysis of natural immunity against defined tumour antigens.