Determination of normal human fetal immunoglobulin M levels.

Immunoglobulin M (IgM) levels were measured in 198 cord blood samples from 192 apparently normal pregnancies from 24 weeks of gestation to term. Simple linear regression analysis yielded a standard curve for IgM development during pregnancy showing a 0.5 mg/dl increase in IgM per week of gestation. This curve allows the comparison of fetal IgM levels from pregnancies considered to be at risk for intrauterine infection.

Efforts to reduce low birth weight and preterm births: a statewide analysis (Virginia).

OBJECTIVE: The purpose of this study was to ascertain the influence of evolving obstetric and public health care on the occurrence of low birth weight and preterm birth in a large population. STUDY DESIGN: Birth statistics of 2,049,970 live births (25.1% nonwhite) and 156,009 low-birth-weight infants (39.8% nonwhite) were analyzed. RESULTS: Between 1967 to 1971 and 1977 to 1981 the incidence of infants weighing < or = 2500 gm declined from 85.5 to 74.4 per 1000 live births. The percentage of 500 to 1500 gm infants delivered at perinatal centers in Virginia increased from 41.8% in 1977 to 1981 to 64.9% in 1987 to 1991. In spite of regionalization, expanded maternity services, and increased use of tocolytic agents the incidence of low-birth-weight infants per 1000 live births in both white and nonwhite populations has remained comparatively stable since 1976, although the percentage of term infants weighing < or = 2500 gm has decreased. The incidence per 1000 live births of infants weighing 500 to 1500 gm has not changed statistically in 25 years (Student t test). CONCLUSION: The data challenge the overall effectiveness of current programs, including the use of tocolytic agents, and indicate a need to restructure efforts to reduce low birth weight and preterm births.

The role of ultrasonography and amniocentesis in the evaluation of pregnancies at risk for neural tube defects.

To assess the relative efficacy of amniocentesis versus targeted (detailed) ultrasonography, 225 patients referred because of an elevated maternal serum alpha-fetoprotein level (79.6%) or a family history of neural tube defect (20.4%) were evaluated. Ultrasonographic examination alone detected all 26 fetal abnormalities (11 cases of anencephaly, 10 cases of open spina bifida, and five other anomalies). Twenty-eight patients declined amniocentesis; all had normal pregnancy outcomes. Of the 167 patients with apparently normal fetal anatomy by sonography, seven had elevated alpha-fetoprotein levels but no acetylcholinesterase in the amniotic fluid. Six of these pregnancies resulted in normal infants; one infant had congenital nephrosis. The remaining 160 patients had normal sonograms with normal amniotic fluid alpha-fetoprotein levels and no fetal malformations at delivery. Although these results suggest that targeted ultrasonography by experienced personnel is a reasonable alternative to amniocentesis in evaluations for neural tube defects, the availability, cost-effectiveness, and diagnostic accuracy of this approach must be well documented in large prospective studies.

Early versus late tocolytic treatment for preterm premature membrane rupture.

The effect of tocolytic therapy before labor was evaluated in 33 pregnant women with preterm premature rupture of the membranes. Either intravenous magnesium sulfate or oral terbutaline was administered at the time of presentation. Intensive surveillance to detect signs of infection was carried out for all patients. In 29 of the patients in this treatment group who were seen at less than 34 weeks, a significantly longer prolongation of pregnancy was achieved when compared with 24 similar women treated after onset of labor in the hospital (169 hours versus 77 hours, p = 0.05). Duration of infant hospitalization was less for those mothers receiving tocolytic agents before labor. Maternal and infant infection were not different in the two groups; nor was the cesarean section rate. When this treatment group was compared with another control group of 96 women already in labor at presentation, the difference in time from admission to delivery was substantial, but it did not achieve statistical significance. In this group the rate of maternal infection was significantly higher, but newborn morbidity was not. Aggressive early treatment with tocolytic agents in pregnant women with preterm premature membrane rupture is more productive but not more dangerous than conservative management.

Fetal evaluation by percutaneous blood sampling.

Percutaneous umbilical blood sampling (cordocentesis) provides direct access to the fetal circulation in the second and third trimesters of pregnancy. Seventeen patients underwent this procedure between December 1985 and December 1986 for evaluation of a variety of clinical situations, including nonlethal fetal abnormalities detected by ultrasound, equivocal results of amniocentesis, nonimmune fetal hydrops, and isoimmune disorders. Our experience confirms the efficacy of the procedure and suggests that it may become an important tool for fetal assessment and therapy.

Glycosylated serum protein level as a screening and diagnostic test for gestational diabetes mellitus.

Glycosylated serum protein assay was examined as an alternative to standard glucose screening and glucose tolerance testing. In a comparison of two groups of gravid women having abnormal 1-hour 50 gm glucose screening tests, there was no difference in glycosylated protein level in the group with abnormal glucose tolerance test results (9.4% +/- 2.0%, mean +/- SD; n = 8) versus normal results (9.2% +/- 1.07%, mean +/- SD; n = 11). Furthermore, correlation of glycosylated serum protein level with glucose screening test results was poor (r = 0.185, p = 0.23, n = 17). Glycosylated serum protein assay is not useful in detecting mild metabolic aberrations associated with gestational diabetes.

Profound hypotension complicating magnesium therapy.

Two preeclamptic women became profoundly hypotensive while receiving magnesium sulfate. No evidence of toxic levels was present in either. In both, preeclampsia-induced hypovolemia was extreme. That nontoxic magnesium levels can cause severe hypotension is an alarming possibility. Acknowledgment of this complication and expeditious reversal of the problem is essential.

Magnesium sulfate and ritodrine hydrochloride: systemic and uterine hemodynamic effects.

Effects of magnesium sulfate and ritodrine hydrochloride on cardiovascular physiologic characteristics were studied in 70 human subjects treated for preterm labor. Systemic and uterine hemodynamic effects were investigated in five pregnant rhesus monkeys. Systolic blood pressure was minimally affected by either agent. Diastolic pressure, while not affected by magnesium sulfate, decreased 26.3% during ritodrine therapy. Maternal and fetal heart rates were minimally affected by magnesium sulfate. Ritodrine increased maternal and fetal heart rates significantly. In the monkeys, magnesium sulfate increased uterine and placental blood flows (by the microsphere technique) but failed to alter cardiac output. Ritodrine produced an increase in cardiac output but decreased perfusion pressure. Placental blood flow decreased by an average of 27.6%. Ritodrine would therefore seem contraindicated with a compromised fetal environment. Magnesium sulfate, by not altering perfusion pressure, may have a beneficial effect on uterine hemodynamics. These specific and distinct differences in cardiovascular and hemodynamic effects should be considered when either magnesium sulfate or ritodrine is selected as a tocolytic agent.

Use of beta-methasone in management of preterm gestation with premature rupture of membranes.

Use of corticosteroids in the management of rupture of the membranes in a preterm gestation was evaluated. Ninety-three mothers (105 infants) received beta-methasone, whereas 105 mothers (112 infants) did not. The incidence of significant neonatal respiratory complications was statistically higher for beta-methasone-treated (26.6%) compared with non-treated patients (11.1%) who delivered more than 48 hours after rupture of membranes. Neonatal septic complications also were significantly higher in treated (21.3%) than in nontreated (9.2%) patients delivered 48 hours after rupture of membranes. Maternal sepsis was not statistically different between the two groups. In the nonsteroid-treated patients, the incidence of significant respiratory distress syndrome was greater for those infants delivered within 48 hours (31.0%) than those delivered more than 48 hours (11.1%) from rupture of membranes. The data support conservative management and indicate that corticosteroid administration in a preterm gestation with rupture of membranes is not beneficial to the newborn.

Prenatal diagnosis of Pena-Shokeir syndrome type 1.

This report describes the sonographic diagnosis of the Pena-Shokeir syndrome type 1 during the second trimester of a pregnancy which was electively terminated. The mother had previously delivered a macerated, hydropic infant with multiple congenital anomalies. The diagnosis was based on the recurrence of hydramnios and nonimmune hydrops in a fetus with normal chromosomes, normal amniotic fluid alpha-fetoprotein, normal fetal echocardiography, and lack of evidence of a lysosomal storage disease. These observations suggest that serial sonography during the second trimester in pregnancies at risk may allow for the prenatal diagnosis of the Pena-Shokeir syndrome type 1. Without further experience, it would not be prudent to suggest to couples at risk that the prenatal diagnosis of a recurrence can be assured with a high degree of accuracy.

The significance of fetal heart rate decelerations during nonstress testing.

Over a 9-month time span, eight gravid women at high risk had fetal heart rate decelerations on nonstress tests (NSTs). This form of antepartum evaluation, the standard at our institution, was performed 918 times on 476 women during this period. Decelerations were required to be between 1 and 10 minutes in duration and less than 90 bpm, or greater than 40 bpm below baseline, for inclusion. Of the eight women (1.7% of the total tested), four had reactive and four nonreactive NSTs. All eight had contraction stress tests (CSTs) that were negative by definition. Of four women allowed to labor, two (50%) required cesarean section for fetal distress. Two instances of fetal death (25%) occurred during observation periods of 36 and 48 hours. Two infants were growth retarded, and two had abnormal cord positions. NSTs showing decelerations of this type, regardless of reactivity or of follow-up CST, are abnormal and should be viewed with alarm. In term pregnancy, such fetuses should be delivered. In preterm pregnancy with nonreactive NSTs, decelerations may also be valid grounds for delivery. Some discrimination is possible in preterm pregnancies when the NST is reactive.

Thrombocytopenia in preeclampsia: associated abnormalities and management principles.

Severe thrombocytopenia, abnormal liver function, and renal dysfunction may occur as manifestations of preeclampsia. Failure to recognize that this cluster of abnormalities represents a form of preeclampsia may result in erroneous initial diagnoses. Management of 13 such patients has shown a direct correlation between the degree of thrombocytopenia and the measures of liver dysfunction. Platelet counts and liver functions improved prior to delivery in five patients treated with corticosteroids. Management should be directed toward investigation and correction of deranged physiology and appropriate monitoring of maternal-feto-placental status. Early delivery is indicated in patients with progressive thrombocytopenia and in those with evidence of fetal maturity or distress. Provided that the disease process remains stable, consideration should be given in cases of fetal immaturity, to the use of betamethasone therapy. The occurrence of severe thrombocytopenia in 20% of neonates should be a consideration in selecting the mode of delivery.

The use of magnesium sulfate as the primary tocolytic agent to prevent premature delivery.

The efficacy of magnesium sulfate was evaluated as the primary tocolytic agent in the management of patients at risk for premature delivery. One hundred ninety-two patients determined to be 36 weeks' gestation or less were treated. One hundred seven patients (55.7%) received an additional oral beta-mimetic agent once labor was arrested. One hundred nineteen patients had intact membranes and 73 patients had ruptured membranes. Delay of delivery of 48 hours or longer was achieved in 70.6% of the patients with intact membranes and 60.2% of patients with ruptured membranes. Intervening obstetric complications, maternal morbidity, and neonatal septic and respiratory morbidity were increased in patients with ruptured membranes compared to patients with intact membranes. Magnesium sulfate is considered to be effective tocolytic agent having minimal adverse effects in managing patients at risk for premature delivery. Its use in patients with ruptured membranes, as with any tocolytic agent, remains controversial.

Biorhythms of the nonpregnant human uterus.

Uterine activity was monitored continuously for periods of three or five days in two subjects. Biorhythms in the spontaneous variations of intrauterine pressure and frequency of contraction were demonstrated in both phases of the menstrual cycle. Statistically, the patterns conformed to 24-hour Fourier curves, with higher values synchronized by the periods of light. Positive statistical correlations were present between uterine activity and the circadian patterns of intrauterine temperature and norepinephrine concentrations in both urine and peripheral arterial plasma.

Effect of betamethasone on fetal macrophage function: depression of adherence of immunoglobulin-coated red blood cells.

In this study, betamethasone was found to significantly inhibit the binding of immunoglobulin-coated O Rh-positive red cells to fetal macrophages. At a dose of 0.15 mg%, betamethasone depressed immune rosette formation to 44% of controls (p less than 0.01); and a dose of 0.60 mg% resulted in an average depression to 22%. This in vitro effect may reflect important alterations in in vivo immune function in infants delivered from mothers who have received antenatal corticosteroids.

Effect of adrenergic blockade on dynamics of the pregnant primate uterus (Macaca mulatta).

Unanesthetized rhesus monkeys, conditioned to restraining chairs and monitored continuously by chronically implanted sensors, were used to explore the relationships between catecholamines and uterine dynamics during late gestation. Continuous intra-aortic infusion of phentolamine produced a dose-response decrease in uterine activity and blood flow. With alpha-adrenergic blockade the circadian (Fourier) variations of uterine activity were abolished and those of uterine blood flow were reversed. Placental blood flow (by the microsphere technique) was 86.1% of control values. Beta-adrenergic blockade (propranolol) accentuated the circadian variations of uterine dynamics. Vascular resistance to both the myometrium and the placentas was increased. The data indicate that the maternal placental vasculature is the primary site of uterine vascular resistance and is susceptible to adrenergic response. The data also suggest that the extrinsic resistance produced by the myometrium is of major importance in the distribution of uterine blood flow.