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Growth of the fetal foot has been monitored by foot length (FL), from 12 to 41 weeks menstrual age in 173 normal Japanese fetuses. Growth curve for this parameter has been determined using a Rossavik growth model [p = c(t)k+s(t)]. R2 value of 98.0% was obtained for FL. Variability analysis indicated some progressive increase in variability with fetal age for this parameter. Variability data were used with the growth curve model to determine standard curve for this parameter. This standard curve provides a superior means for evaluating the normal fetal foot growth in the fetus and for assessing menstrual age in utero.

To search for possible effect of dehydroepiandrosterone sulfate (DHAS) on maternal cardiac function in term pregnancy, impedance cardiographic assessments were made on 15 normal full-term pregnant women before and 5, 10, 15, 20, 25, and 30 minutes after the administration of a 200 mg intravenous dose of DHAS in 20 mL of 5% dextrose. The cardiac output, stroke volume, heart rate, and mean arterial pressure were recorded. Maternal cardiac output increased from baseline by 20% (p < 0.05) after 15 minutes and the mean increase in stroke volume was 25% (p < 0.05) after 15 minutes. No change was found in heart rate or mean arterial blood pressure. DHAS induces a significant increase in both maternal stroke volume and cardiac output without change in heart rate or mean arterial pressure, which suggests a possible increase in cardiac contractility in term pregnancy.

The effect of maternal hyperglycemia on fetal regional circulation in appropriate for gestational age and small for gestational age fetuses was evaluated. Color Doppler flow imaging and pulsed Doppler ultrasonographic assessments were made on 15 appropriate for gestational age and 19 small for gestational age fetuses, ranging from 33 to 40 weeks' gestation before, 60 minutes, and 120 minutes after a maternal 75 g glucose load. The pulsatility index (PI) was calculated for middle cerebral artery, descending aorta, splenic artery, renal artery, femoral artery, and umbilical artery. Simultaneously, maternal plasma glucose concentration was measured. Baseline PI value (1.50 +/- 0.31) for middle cerebral artery in small for gestational age fetuses was significantly lower than that (1.89 +/- 0.37) in appropriate for gestational age fetuses (p < 0.05); however, there were no significant differences in baseline PI values for other arteries in both groups. In appropriate for gestational age fetuses, the mean PI decreased from 1.89 +/- 0.37 to 1.47 +/- 0.33 at 60 minutes, and to 1.55 +/- 0.32 at 120 minutes (p < 0.05), but no changes were found in the other arteries. In small for gestational age fetuses, there was no significant change in PI value for each artery before and after maternal glucose load. Maternal hyperglycemia induces a significant decrease in cerebrovascular resistance in appropriate for gestational age fetuses but not in small for gestational age fetuses. These results provide a foundation for evaluating the effect of maternal hyperglycemia on fetal regional circulation.

Nifedipine has been used to treat hypertension in pregnancy, and does not influence fetal or uteroplacental circulations in patients with preeclampsia. A 29-year-old multi-gravid woman presented at 32 weeks' gestation with significant elevation of her blood pressure. After sublingual administration of nifedipine, the blood pressure decreased from 208/122 to 136/96 mm Hg at 30 minutes. In her growth-retarded fetus with abnormal flow velocity waveforms, pulsatility index values for middle cerebral artery and umbilical artery did not change; however, peak systolic velocities, end-diastolic velocities, and time-averaged mean peak velocities for these arteries became significantly elevated. Simultaneously, severe variable decelerations and late decelerations occurred. The adverse effect of nifedipine on fetal circulation might occur in a growth-retarded fetus with abnormal flow velocity waveforms.

The possible effects of dehydroepiandrosterone sulfate on orbital circulation in 14 term pregnant women were examined by color Doppler flow mapping and pulsed Doppler ultrasound assessments of ophthalmic artery blood flow velocities before and 3 minutes after the intravenous drug injection. Blood pressure, heart rate, peak systolic velocity, end-diastolic velocity, time-averaged mean peak velocity, and pulsatility index were studied. Dehydroepiandrosterone sulfate injected intravenously had little effect on blood pressure, heart rate, and peak systolic velocity, increasing (p < 0.02) the mean end-diastolic velocity from 3.7 +/- 1.7 to 4.9 +/- 2.0 cm/s (mean +/- SD) and the mean time-averaged mean peak velocity (p < 0.02) from 9.8 +/- 3.2 to 12.1 +/- 3.9 cm/s (mean +/- SD). The mean pulsatility index decreased simultaneously (p < 0.02) from 2.75 +/- 0.79 to 2.29 +/- 0.58 (mean +/- SD). Dehydroepiandrosterone sulfate vasodilates the ophthalmic artery, increasing blood flows in term pregnant women, and similar changes might occur in other cerebral vessels. It seems that this vasodilative effect of dehydroepiandrosterone sulfate is expected for treatment of preeclampsia.

Growth of the fetal lung has been monitored by left lung area (LLA), right lung area (RLA), and total lung area (TLA) from 14 to 41 weeks menstrual age in 116 normal Japanese fetuses. Growth of the fetal heart and chest has also been monitored by heart area (HA) and chest area (CA), respectively. Growth curves for these parameters have been determined by using a Rossavik growth model [p = c(t)k+s(t)]. R2 values of 95.3%, 90.3%, 89.0%, 88.7%, and 92.1% were obtained for CA, HA, LLA, RLA, and TLA, respectively. Variability analysis indicated a progressive increase in variability with fetal age for these five parameters. Variability data were used with the growth curve models to determine standard curves for these parameters. These standard curves provide a superior means for evaluating the normal fetal lung growth in the fetus and for identifying pulmonary hypoplasia in utero.

Growth of the fetal cardiac ventricle has been monitored by total cardiac diameter (TCD), left ventricular systolic (LVSD) and diastolic diameter (LVDD), right ventricular systolic (RVSD) and diastolic diameter (RVDD), left ventricular width (LVW), interventricular septal width (IVSW), and right ventricular width (RVW) from 19 to 39 weeks, menstrual age, in 114 normal Japanese fetuses. Growth curves for these parameters have been determined using a Rossavik growth model [P = c(t)k+s(t)]. R2 values of 89.7, 58.0, 65.3, 77.9, 80.3, 31.1, 30.1, and 26.9 were obtained for TCD, LVSD, LVDD, RVSD, RVDD, LVW, IVSW, and RVW, respectively. Variability analysis indicated a progressive increase in variability with fetal age for these eight parameters. Variability data were used with the growth curve models to determine standard curves for these parameters. These standard curves provide a superior means for evaluating the normal fetal cardiac growth in the fetus and for identifying congenital heart anomalies in utero.

To assess the growth of the fetal liver in normal pregnancies and evaluate the ability of fetal liver length measurement for prediction of small for gestational age fetuses, ultrasonographic examinations were performed on 162 normal fetuses, ranging from 15 to 40 weeks menstrual age. The optimal mathematical function and normal range of liver length were generated. The liver length was obtained in 21 small for gestational age fetuses between 34 and 40 weeks, and the ability to use fetal liver length measurement for prediction of small for gestational age fetuses was investigated. A curvilinear relationship was found between the menstrual age and liver length (R2 = 91.9%), and a normal range of liver length measurement for estimating the growth of the fetal liver during normal pregnancy was generated. The liver length was normal in 19 of 21 small for gestational age fetuses (90.5%). The fetal liver length measurement does not provide a superior means for identifying the small for gestational age fetus.

Growth of the fetal adrenal gland has been monitored by measurements of the circumference (AGC) and area (AGA) of the adrenal gland from 16 to 40 weeks menstrual age. Growth curves for these parameters have been determined using a Rossavik growth curve models [P = c(t)k + s(t)]. R2 values of 86.2 and 91.1% were obtained for AGC and AGA, respectively. Variability analysis indicated a progressive increase in variability with menstrual age for these two parameters. Variability data were used with the growth curve models to determine standard curves for AGC and AGA. These standard curves provide a superior means for evaluating the adrenal growth in the fetus and the fetal status in utero in high-risk pregnancies.

Echocardiographic assessments of fetal and neonatal systolic time intervals were made to determine differences in circulatory changes in 40 neonates delivered vaginally and 30 delivered by elective cesarean section. Left preejection period (LPEP), left ventricular ejection time (LVET), LPEP/LVET, right preejection period (RPEP), right ventricular ejection time (RVET), RPEP/RVET, and heart rate were determined at various time points from antenatal to 120 hours after delivery. There were no significant changes in left systolic time intervals between the two groups at any various time points. However, RPEP and RPEP/RVET values were significantly higher in the cesarean section group than in those in normal vaginal delivery group within 12 hours after delivery. These results suggest that the transient pulmonary hypertension after delivery is prolonged in babies delivered by elective cesarean section.

To assess the growth and function of the fetal spleen, ultrasonographic examinations were performed on 229 normal fetuses, ranging from 20 to 41 weeks, menstrual age. Curvilinear relationships were found between the menstrual age and splenic length (R2 = 92.7%), circumference (R2 = 93.9%), and area (R2 = 95.2%). A normal range of splenic length, circumference, and area measurements for estimating the growth of the fetal spleen during normal pregnancy was generated. Splenic parameter values just after delivery were significantly lower than those measured within 7 days before delivery, and returned to former sizes 24 hours later, in both vaginal delivery and cesarean section groups. Splenic parameter values in the vaginal delivery group were also significantly lower than those in the cesarean section group, just after delivery. Moreover, neonatal splenic length showed negative correlations with lactate dehydrogenase (p < 0.001) and glutamic oxaloacetic transaminase (p < 0.05) in the umbilical venous blood, respectively. These results provide a foundation for the evaluation of fetal splenic growth and function during pregnancy and the early neonatal period.