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Doctors need to create a database to gather information about the best way to treat peripartum cardiomyopathy. This is a heart disease that occurs shortly after childbirth. It is uncommon and for that reason, many doctors do not know exactly how to treat it.

Researchers report the first known study that analyzed how the fetal heart fills after each contraction beginning at the 16th week of pregnancy and continuing to the age of 12 months after birth. Doppler ultrasound was used to determine filling patterns at 16 weeks, every 4-6 weeks thereafter until birth, and at the ages of 1 and 2 days, 6 weeks, 6 months and one year. Results show that the fetal heart has filling properties similar to adults with heart disease. The heart was stiffer and the right side of the heart was dominant rather than the left.

Pregnancy may normally be associated with electrocardiographic changes during exercise. Researchers obtained electrocardiograms from 39 pregnant women in early and late pregnancy and from eight nonpregnant women during bicycle exercise tests. Pregnant women exhibited more T-wave inversions in V2 than nonpregnant women. In late pregnancy, women had much fewer small Q waves. Pregnant women achieved maximum ST depression much sooner than nonpregnant women during exercise. Pregnant women did not experience any adverse cardiac effects from exercise.

Estrogen may enhance blood vessel dilation and increase nitric oxide production in the nonpregnant uterus. Researchers used 10 nonpregnant sheep that had never borne offspring and whose ovaries had been removed to determine the effect of estrogen on arteries of the uterus and kidneys and the relationship of nitric oxide to that effect. Estrogen enhanced the ability of bradykinin and superoxide dismutase to dilate blood vessels of the uterus but not of the kidneys. Nitric oxide may play a role in the vasodilating effect of estrogen on uterine arteries. Administration of an inhibitor of nitric oxide production caused a decrease in the vasodilating effect of estrogen. Elevations in nitric oxide production may induce the increase in blood volume in the sheep uterus during heat.

The presence of certain indicators in cervical fluid and blood plasma may predict preterm labor and delivery before 34 weeks of pregnancy. Researchers studied 37 patients with preterm labor. Twenty-nine women had fetal fibronectin in the cervical fluid, and 89% of these were delivered before 34 weeks of pregnancy. Elevated plasma C-reactive protein levels were associated with high interleukin-6 levels in amniotic fluid, and seven of eight women with the latter marker did not respond to attempts to stop labor with drugs. Women with both fetal fibronectin and high interleukin-6 levels may not respond to attempts to stop labor, and are likely to deliver prematurely. These noninvasive tests may reduce the need for amniocentesis to predict preterm labor and delivery.

An episode of tachycardia (abnormally rapid heart rate) or bradycardia (abnormally slow heart rate) during labor may be associated with neonatal death among infants born between 24 and 26 weeks' gestation. Electronic fetal monitor tracings during the last hour of labor were evaluated for 41 infants born between 24 and 26 weeks' gestation. Nineteen had at least one episode of bradycardia or tachycardia and 22 did not. Among the 19, 53% died versus 14% among those with neither complication. Other adverse outcomes - Apgar score less than or equal to 3 at 5 minutes, cord blood pH less than or equal to 7, the incidence of ventricular hemorrhage, more than 42 days on assisted ventilation, more than 90 days of hospitalization, mental retardation at one year, cerebral palsy at one year - were similar. No other types of fetal heart rate abnormalities correlated with outcome. Interpretation of results is limited by the small number of subjects in the study.

Obese patients may maintain normal cardiac function in the third trimester of pregnancy, although obesity leads to higher cardiac output, and pregnancy is an additional stressor. Echocardiographic study was done on eight healthy obese (150% of ideal body weight) women in the third trimester of pregnancy and compared with studies of 36 normal weight women in the third trimester. The left ventricle was enlarged in obese women, but not more than is found in healthy normal weight pregnant women. The ventricular walls were thicker in the obese group. Cardiac function was similar to that of normal weight women. These results may not apply to pregnant women of greater degree of obesity nor to women with medical problems affecting cardiac function.

The blood flow in the brain (cerebral blood flow) can be measured using Doppler ultrasound, the use of high frequency sound to study the movement of fluids. It is suspected that the blood flow in the cerebral artery in the brain of growth-retarded fetuses is altered. The middle cerebral arteries in the brains of 17 small-for-gestational-age (SGA) fetuses were studied. The Doppler results were compared with 25 appropriately sized fetuses. The blood pressure in the umbilical artery differed between SGA and normal sized fetuses. The two indices used in this assessment are not absolute measurements of blood flow but of the resistance of blood flow through the blood vessel. There was no difference in the Doppler pattern produced by blood flow in the middle cerebral artery between the age-matched growth-retarded and normal sized fetuses. A study measuring the change in blood flow as the fetus becomes growth retarded is suggested. (Consumer Summary produced by Reliance Medical Information, Inc.)

Prolonged pregnancies complicated by oligohydramnios may be characterized by changes in the blood flow of the fetal kidneys. An oligohydramnio is a deficiency of amniotic fluid. Among 50 women who were 40 or more weeks pregnant, 33 had a normal amniotic fluid index and 17 had a low amniotic fluid index. The amniotic fluid index is a measurement of amniotic fluid volume. Fetuses with a low amniotic fluid index were more likely to have changes in the blood flow of the renal artery of the fetus. Blood flow in the umbilical artery was the similar for the two groups. A significant decrease in amniotic fluid is associated with both term and post-term pregnancies.