Biomedical subjects

M Miodovnik

Publications and source records attributed to M Miodovnik.

At least 73 records · Page 4Linked to original sources

PubMed1996

The preterm prediction study: a clinical risk assessment system.

OBJECTIVE: Our aims were to develop a risk assessment system for the prediction of spontaneous preterm delivery using clinical information available at 23 to 24 weeks' gestation and to determine the predictive value of such a system. STUDY DESIGN: A total of 2929 women were evaluated between 23 and 24 weeks' gestation at 10 centers. Demographic factors, socioeconomic status, home and work environment, drug and alcohol use, and medical history were evaluated. Information regarding symptoms, cultures, and treatments in the current pregnancy were ascertained. Anthropomorphic and cervical examinations were performed. Univariate analysis and multivariate logistic regression were performed in a random selection, constituting 85% of the study population. The derived risk assessment system was applied to the remaining 15% of the population to evaluate its validity. RESULTS: A total of 10.4% of women were delivered of preterm infants. The multivariate models for spontaneous preterm delivery were highly associated with spontaneous preterm delivery (p < 0.0001). A low body mass index (<19.8) and increasing Bishop scores were significantly associated with spontaneous preterm delivery in nulliparous and multiparous women. Black race, poor social environment, and work during pregnancy were associated with increased risk for nulliparous women. Prior obstetric outcome overshadowed socioeconomic risk factors in multiparous women with a twofold increase in the odds of spontaneous preterm delivery for each prior spontaneous preterm delivery. Current pregnancy symptoms, including vaginal bleeding, symptomatic contractions within 2 weeks, and acute or chronic lung disease were variably associated with spontaneous preterm delivery in nulliparous and multiparous women. When the system was applied to the remainder of the population, women defined to be at high risk for spontaneous preterm delivery (> or = 20% risk) carried a 3.8-fold (nulliparous women) and 3.3-fold (multiparous women) higher risk of spontaneous preterm delivery than those predicted to be at low risk. However, the risk assessment system identified a minority of women who had spontaneous preterm deliveries. The sensitivities were 24.2% and 18.2% and positive predictive values were 28.6% and 33.3%, respectively, for nulliparous and multiparous women. CONCLUSIONS: Although it is possible to develop a graded risk assessment system that includes factors that are highly associated with spontaneous preterm delivery in nulliparous and multiparous women, such a system does not identify most women who subsequently have a spontaneous preterm delivery. This system has investigational value as the basis for evaluating new technologies designed to identify at-risk subpopulations.

Black People↗

PubMed1996

Does pregnancy increase the risk for development and progression of diabetic nephropathy?

OBJECTIVE: This study was designed to determine whether pregnancy and increasing parity in women with insulin-dependent diabetes mellitus (1) increases the risk for diabetic nephropathy and (2) accelerates the progression of diabetic nephropathy. STUDY DESIGN: The study included women with insulin-dependent diabetes mellitus who enrolled in our diabetes-in-pregnancy trial with a pregnancy that continued beyond 20 weeks' gestation and who were delivered between 1978 and December 31, 1991, to allow for a minimum of 3 years' follow-up. Pregnancy and follow-up information was obtained from the medical records and from our computerized database. For patients followed up elsewhere, information was obtained from their current physicians. Life-table analysis was used to determine (1) the risk for nephropathy developing de novo as a function of duration of disease and the association of this risk with parity and (2) the risk of renal failure developing in women with preexisting nephropathy and its association with parity. RESULTS: The study population included 182 pregnant women with insulin-dependent diabetes mellitus: 46 with overt nephropathy (group F) and 136 without nephropathy (group NF). Pregnancy and increasing parity did not increase the overall risk for nephropathy (44% after 27 years of diabetes). In group NF 10% had nephropathy within 10.1 +/- 4.2 years of the pregnancy. Proteinuria appearing during pregnancy and glycemic control during pregnancy were significantly associated with the subsequent development of nephropathy. In group F 26% had end-stage renal disease after a median period of 6 years from the pregnancy. Pregnancy or increasing parity did not increase the risk for renal failure in women with nephropathy. CONCLUSIONS: Our data support the premise that pregnancy in women with insulin-dependent diabetes mellitus does not increase the risk of subsequent nephropathy and does not accelerate progression of renal disease in women with preexisting nephropathy.

Black People↗

PubMed1996

The preterm prediction study: risk factors in twin gestations. National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.

OBJECTIVE: Our purpose was to determine the association between the presence of bacterial vaginosis, fetal fibronectin, and a short cervix and the risk of spontaneous preterm birth of twins. STUDY DESIGN: We prospectively screened 147 women with twins at 24 and 28 weeks' gestation for more than 50 potential risk factors for spontaneous preterm birth. We also measured cervical length with ultrasound scans and tested for the presence of bacterial vaginosis. Fetal fibronectin level was evaluated every 2 weeks from 24 to 30 weeks' gestation. Outcomes included spontaneous preterm birth at < 32 weeks, < 35 weeks, and < 37 weeks. RESULTS: Among twin as compared with singleton pregnancies, a cervical length < or = 25 mm was more common at both 24 and 28 weeks, a statistically significant difference. There were no significant differences in most other risk factors. Of the factors evaluated by means of univariate analysis at 24 weeks, only a short cervix (< or = 25 mm) was consistently associated with spontaneous preterm birth. The odds ratio and 95% confidence interval for spontaneous preterm birth at < 32 weeks, < 35 weeks, and < 37 weeks were 6.9 (2.0 to 24.2), 3.2 (1.3 to 7.9), and 2.8 (1.1 to 7.7). At 28 weeks, a cervical length < or = 25 mm was not a strong predictor of spontaneous preterm birth. At both 28 weeks (odds ratio, 9.4; confidence interval, 1.0 to 67.7) and 30 weeks (odds ratio 46.1; confidence interval, 4.2 to 1381), a positive fetal fibronectin result was significantly associated with spontaneous preterm birth at < 32 weeks. Bacterial vaginosis at 24 or 28 weeks was not associated with spontaneous preterm birth of twins. Multivariate analysis confirmed the association between cervical length < or = 25 mm at the 24-week visit and spontaneous preterm birth and also confirmed that at 24 weeks the other risk factors were less consistently and often not statistically significantly associated with spontaneous preterm birth. Of the risk factors evaluated at 28 weeks, only a positive fetal fibronectin was associated with a significantly increased risk for spontaneous preterm birth. CONCLUSIONS: Most known risk factors for spontaneous preterm birth were not significantly associated with spontaneous preterm birth of twins. At 24 weeks, cervical length < or = 25 mm was the best predictor of spontaneous preterm birth at < 32 weeks, < 35 weeks, and < 37 weeks. Of the risk factors evaluated at 28 weeks, fetal fibronectin was the only statistically significant predictor of spontaneous preterm birth at < 32 weeks.

Adolescent↗

PubMed1996

Successful pregnancy after combined renal-pancreas transplantation: a case report and literature review.

A long-standing history of insulin-dependent diabetes mellitus can result in multiple organ damage. We present a case of successful pregnancy in a patient who underwent combined renal-pancreas transplantation for end-stage renal disease due to diabetic nephropathy. A 29-year-old white gravida 7, para 2 female was diagnosed with diabetes mellitus at age 7. She was well controlled with insulin until age 21. She developed complications of diabetes mellitus which included retinopathy resulting in legal blindness, nephropathy resulting in end-stage renal disease, and chronic hypertension. Following nine months of dialysis she underwent a combined renal-pancreas transplant. She subsequently became pregnant 21 months after transplantation and delivered a healthy male at 35 1/2 weeks gestation. Renal-pancreas transplant recipients who become pregnant may be at an increased risk for adverse outcome. We present a successful pregnancy outcome in a combined transplant recipient who had a prior poor obstetrical history.

Adult↗

PubMed1996

Common clinical manifestations of maternal diabetes in newborn infants: implications for the practicing pediatrician.

Even though perinatal mortality of infants of diabetic mothers has decreased remarkably in recent years and now approaches that of the general population, these infants still face a multitude of potential complications and the propensity for increased morbidity, both in utero and postnatally. Many of these complications are clearly related to the metabolic status of the diabetic mother. Increasing awareness among insulin-dependent diabetic patients and health providers of the need for glycemic control and the ever-growing understanding of the peculiarities of diabetic pregnancies eventually should combine to provide the best possible outcome for these infants.

Abnormalities, Multiple↗

PubMed1995

Lack of effect of pregnancy on renal allograft survival or function.

To determine whether pregnancy had a long-term influence on the survival or function of renal allografts, a case-control study was conducted. Patients were selected from a pool of 915 patients transplanted at the University of Cincinnati from 1967 to 1990. The pregnancy group consisted of 18 women who became pregnant 3 months to 17 years after transplantation and who elected to continue pregnancy. There were 26 nonpregnant female controls, and 23 male control renal transplant recipients. Matching criteria were cause of end-stage renal disease (ESRD), donor source, age at transplantation, calendar year of transplantation, time from transplantation to pregnancy, and serum creatinine concentration at the time corresponding to conception. Matching was performed by one investigator, who had no knowledge of long-term outcome in any of the patients. The three groups were well-matched with regard to these criteria. Male controls had higher baseline creatinine clearances than pregnancy cases or female controls. During pregnancy, serum creatinine levels fell by 20%, and creatinine clearance rose by 53%. Immediately after pregnancy, these values returned to baseline. Graft survival, with a mean posttransplant follow-up of 11-12 years, was 77.8% in the pregnancy cases, 69.2% in the female controls, and 69.6% in the male controls. By life-table analysis, none of these differences was significant. Among surviving grafts, serum creatinine levels and creatinine clearances remained stable throughout the follow-up period. In this study, using well-matched male and nonpregnant female cohorts for comparison, pregnancy did not have an adverse long-term effect on renal allograft function or survival.

Adult↗

PubMed1995

The action of two natriuretic peptides (atrial natriuretic peptide and brain natriuretic peptide) in the human placental vasculature.

OBJECTIVE: Our purpose was to compare the actions of atrial natriuretic peptide and brain natriuretic peptide in the human placental vasculature. STUDY DESIGN: Isolated placental cotyledons were dually perfused with fetal perfusion pressure used as an index of vascular response. The effect of angiotensin II (10(-10) to 10(-6) mol/L bolus injection) was established in the absence or presence of atrial natriuretic peptide (10(-8) mol/L) or brain natriuretic peptide (10(-8) mol/L final concentration). The role of nitric oxide as a mediator of natriuretic peptide action was investigated by perfusion of n-nitro-L-arginine (10(-3) mol/L), an inhibitor of nitric oxide synthase. Attenuation of the action of atrial natriuretic peptide by placental peptidases was studied by perfusion with the peptidase inhibitor benzamidine (2 x 10(-2) mol/L). Statistical significance was determined by analysis of variance and paired t test. RESULTS: Significant attenuation of vasoconstrictor responses to angiotensin II occurred within both atrial natriuretic peptide and brain natriuretic peptide; however, brain natriuretic peptide was more effective. n-Nitro-L-arginine did not affect the attenuation of angiotensin II-induced vasoconstriction by atrial or brain natriuretic peptides. In the presence of benzamidine atrial natriuretic peptide exerted a significantly greater vasodilator effect. CONCLUSION: Brain natriuretic peptide is a more potent vasodilator of the placental vasculature than is atrial natriuretic peptide. The low efficacy of atrial natriuretic peptide may be related to placental peptidases. Nitric oxide does not mediate the action of atrial natriuretic peptide or brain natriuretic peptide.

Angiotensin II↗

PubMed1995

The interaction of nitric oxide and superoxide in the human fetal-placental vasculature.

OBJECTIVE: Our purpose was to study the interaction of nitric oxide and superoxide anion on the vasculature of the isolated perfused human placental cotyledon. STUDY DESIGN: Isolated placental cotyledons were preconstricted with the thromboxane mimetic U46619, and fetal perfusion pressure was used as an index of response. The interaction of nitric oxide and O2- was studied by three protocols: (1) with endogenous nitric oxide, (2) with addition of exogenous nitric oxide, and (3) with inhibition of nitric oxide synthesis by the nitric oxide synthase inhibitor N-nitro-L-arginine. O2- was generated by infusion of purine-xanthine oxidase. Statistical significance of response to treatment was determined by paired t test. RESULTS: Infusion of xanthine oxidase with purine in the presence of endogenous nitric oxide resulted in vasodilation (p < 0.05). Vasodilation was more pronounced in the presence of exogenous nitric oxide (p < 0.008). Coinfusion of xanthine oxidase with purine in the presence of N-nitro-L-arginine to inhibit nitric oxide synthesis resulted in vasoconstriction. CONCLUSION: We conclude that, rather than superoxide inactivating nitric oxide, interaction of the two radicals generates in the placental vasculature a vasodilator, which may be peroxynitrite.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

PubMed1995

Interaction of angiotensin II and brain natriuretic peptide in the placentas of normal and diabetic women.

OBJECTIVE: To evaluate the effects of angiotensin II and brain natriuretic peptide on the placental vasculature of diabetic women. METHODS: Term placentas from five diabetic women and five nondiabetic controls were collected. Isolated placental cotyledons were perfused dually with fetal perfusion pressure as an index of vascular response. The effect of angiotensin II (10(-10)-10(-5) mol/L bolus injection) was established in the fetal-placental vasculature of all placentas in the absence or presence of brain natriuretic peptide (10(-8) mol/L final concentration). Data were analyzed using repeated measures analysis of variance and paired t test where appropriate. RESULTS: A significant vasoconstrictor response to angiotensin II was achieved in placentas of both diabetic and nondiabetic women (P < .001); however, the angiotensin II-induced increase in perfusion pressure was significantly greater in the diabetic group (P < .01). Significant attenuation of vasoconstrictor response to angiotensin occurred in the presence of brain natriuretic peptide in placentas of both nondiabetic (P < .0025) and diabetic (P < .025) women, but the effect was more prominent in the diabetic group. CONCLUSION: The in vitro placental vasculature of diabetic women is more sensitive to angiotensin II than is the in vitro placental vasculature of nondiabetic women. The attenuation exerted by brain natriuretic peptide on angiotensin II-induced vasoconstriction is more prominent in placentas from diabetic women compared to those from nondiabetic women.

Adult↗

PubMed1995

Hypoglycemia: the price of intensive insulin therapy for pregnant women with insulin-dependent diabetes mellitus.

OBJECTIVE: To evaluate the risk of hypoglycemia associated with intensive insulin therapy of type I diabetes during pregnancy. METHODS: Eighty-four women with type I diabetes were recruited before 9 weeks' gestation and received intensive insulin therapy throughout pregnancy. Patients monitored glucose concentrations with memory glucometers, and insulin dosages were adjusted weekly accordingly. A detailed history of clinical hypoglycemic events was obtained at each weekly clinic visit. RESULTS: Clinically significant hypoglycemia requiring assistance from another person occurred in 71% of pregnant patients, with a peak incidence between 10-15 weeks. Severe hypoglycemia during the early weeks of embryogenesis was not associated with an increase in embryopathy. Glycemic control was similar in women with or without recurrent hypoglycemia, but glucose fluctuations were significantly greater in hypoglycemic women. CONCLUSION: Severe hypoglycemia is a significant maternal risk associated with intensive insulin therapy of pregnant women with type I diabetes. In women with recurrent episodes of hypoglycemia, the clear benefits of strict glycemic control must be weighed against the hazards of hypoglycemia.

Adult↗

PubMed1995

Pregnancy in a combined liver and kidney transplant recipient with type 1 primary hyperoxaluria.

BACKGROUND: Little is known about pregnancy outcomes in multiple organ transplant recipients. We present a case of pregnancy in a patient after liver and kidney transplantation for the genetic disorder of type 1 primary hyperoxaluria. CASE: A 14-year-old Hispanic teenager presented with end-stage renal disease and had a kidney biopsy that revealed hyperoxaluria. A liver biopsy revealed type 1 primary hyperoxaluria. After a year of dialysis and worsening renal status, she underwent a combined orthotopic liver and kidney transplant. The patient subsequently became pregnant, but she required no antihypertensive therapy throughout the prenatal or postpartum period and showed no signs of renal or liver graft rejection. She delivered by cesarean at 38 weeks. CONCLUSION: Combined liver and kidney transplant recipients who become pregnant can have a successful outcome.

Adolescent↗

PubMed1995

In situ human obstetrical ultrasound exposimetry: estimates of derating factors for each of three different tissue models.

A specialized in vivo exposimetry system was developed to acquire transabdominal in situ ultrasound exposure quantities in obstetric patients. Under surgical conditions, the sterilized 7-element calibrated linear array hydrophone was introduced into the uterus under direct ultrasound guidance and placed in direct contact with the products of conception, usually in the saggital midplane of the uterine cavity. Twenty-five patients with empty bladders and 10 patients with full bladders were studied at gestational ages between 7 and 20 weeks. In the empty bladder condition, the sound beam traversed the anterior abdominal wall, uterus, amniotic fluid and fetal parts and in the full bladder condition, the sound beam also traversed the fluid-filled bladder. Each study was conducted with a 3 MHz, mechanical sector transducer in combination with an ATL Ultramark 4 diagnostic ultrasound imaging system. Calibration data were recorded after completion of each in vivo patient study. The acquired exposimetry data from the 35 obstetric patients were used to evaluate the appropriateness of three tissue attenuation models, viz., fixed path, homogeneous and overlying. All three tissue models yield a mean attenuation coefficient value of about a factor of 3 to 4 greater than their respective minimum values. In the case of the overlying and homogeneous tissue models, there was a statistically significant correlation between their calculated attenuation coefficients and total distance for the combined data set whereas there was no such dependency for the calculated fixed-path tissue model. In summary, any one of the three tissue models may be used to estimate in utero acoustic quantities during the first and second trimesters of human pregnancy based on this study.

Adult↗

PubMed1995

Evidence of increased intrauterine bone resorption in term infants of mothers with insulin-dependent diabetes.

Infants of diabetic mothers (IDMs) have lower bone mineral content than control subjects at birth. We measured cord blood propeptide of type I procollagen (PICP), a marker of bone formation, and telopeptide of type I collagen (ICTP), a marker of bone resorption, in 25 term IDMs and 20 term control subjects. Concentrations of ICTP were higher in IDMs than in control subjects; there was no difference in PICP concentrations. We conclude that osteoclastic activity appears to be higher in IDMs than in control subjects in utero.

Adult↗

PubMed1995

Normalization of blood glucose in insulin-dependent diabetic pregnancies and the risks of hypoglycemia: a therapeutic dilemma.

Intensive insulin therapy delays the onset and progression of microvascular complications in insulin-dependent diabetes mellitus (IDDM). Such therapy, however, is associated with an increased risk of potentially life-threatening hypoglycemia due to the loss of normal counterregulatory hormonal responses to hypoglycemia and to the syndrome of hypoglycemia unawareness. Current standards for glycemic control during pregnancy in IDDM women require intensive insulin therapy to optimize pregnancy outcome. Therefore, obstetricians and gynecologists providing prenatal care for women with IDDM should be aware that intensive insulin therapy predisposes these patients to the significant risks of severe hypoglycemia. It often becomes necessary to individualize the optimal balance between glycemic control during pregnancy and the risks of hypoglycemia.

Blood Glucose↗

PubMed1994

Glycemic thresholds for spontaneous abortion and congenital malformations in insulin-dependent diabetes mellitus.

OBJECTIVE: To test the hypothesis that women with insulin-dependent (type I) diabetes have a threshold of glycemic control in early pregnancy for increased risks of spontaneous abortion and congenital malformations. METHODS: Receiver-operating characteristic (ROC) curves were formed for the occurrence of abortion and malformations as a function of the median first-trimester preprandial blood glucose concentration and the first measured glycohemoglobin concentration in pregnant women with type I diabetes. RESULTS: Fifty-two of the 215 women (24%) who enrolled before 9 weeks' gestation had spontaneous abortions. Six percent of the women enrolled before 14 weeks had infants with major congenital malformations. Thresholds for an increased risk of abortion and malformations were a median first-trimester blood glucose concentration of 120-130 mg/dL or an initial glycohemoglobin concentration of 12-13% (6.2-7.5 standard deviations above the normal mean). CONCLUSIONS: Type I diabetic women with initial glycohemoglobin concentrations in pregnancy above 12% or median first-trimester preprandial glucose concentrations above 120 mg/dL have an increased risk of abortion and malformations. Below these glycemic thresholds, the risks are comparable to those in nondiabetic women.

Abortion, Spontaneous↗

PubMed1994

Maternal floor infarction of the placenta: prenatal diagnosis and clinical significance.

OBJECTIVE: To determine whether maternal floor infarction can be diagnosed prenatally. METHODS: We reviewed the charts of 13 patients with maternal floor infarction confirmed histopathologically to determine the frequency of increased placental echogenicity, fetal growth restriction (FGR), and oligohydramnios. Subsequently, we applied these criteria prospectively to diagnose maternal floor infarction in three cases. RESULTS: Twelve of the 13 pregnancies reviewed retrospectively resulted in small for gestational age infants, of which eight were stillbirths. Fetal growth restriction and oligohydramnios were evident on ultrasound in five pregnancies and a placental abnormality was noted in four; two patients exhibited this complete triad of sonographic abnormalities. Three patients were identified prospectively with maternal floor infarction based on sonographic findings and electively delivered live preterm infants. CONCLUSIONS: Maternal floor infarction is a placental condition with profound risk for FGR and stillbirth. Antenatal diagnosis may improve the perinatal outcome with this condition.

Adult↗

PubMed1993

Poor glycemic control and antepartum obstetric complications in women with insulin-dependent diabetes.

OBJECTIVE: The purpose of this study was to test the hypothesis that the rate of complications of pregnancy in women with insulin-dependent diabetes is higher than in nondiabetic women and is associated with poor glycemic control and microvascular disease. METHOD: Women who enrolled in a multidisciplinary program of diabetes in pregnancy prior to 20 weeks' gestation were included in the study and matched 1:2 by age, race and parity to a control group of nondiabetic women. Complications of pregnancy were retrospectively analyzed and compared between groups. The association of complications with glycemic control and microvascular disease was analyzed within the diabetic group. RESULT: Women with diabetes had significantly higher rates of pregnancy-induced hypertension (PIH), polyhydramnios, pyelonephritis, preterm delivery and meconium-stained amniotic fluid. Poor glycemic control, particularly during the first and second trimesters of pregnancy, was associated with all complications, except pyelonephritis. Microvascular disease was associated with PIH and preterm delivery prior to 34 weeks. CONCLUSION: Women with insulin-dependent diabetes are at high risk for complications of pregnancy. Glycemic control during the first and second trimesters may affect events later in pregnancy.

Blood Glucose↗

PubMed1993

Diabetic fetal macrosomia: significance of disproportionate growth.

Fetal hyperinsulinism in infants of diabetic mothers (IDMs) produces increased fetal growth leading to macrosomia, which may or may not be proportionate. Disproportionate macrosomia refers to excessive weight characterized by a high weight/length ratio. We tested the hypotheses that (1) macrosomia in IDMs would be characterized by a high ponderal index (defined as weight/length ratio) and (2) infants with macrosomia who have a high ponderal index would have increased neonatal morbidity--specifically, hyperbilirubinemia, hypoglycemia, polycythemia, and acidosis. We studied 170 IDMs and 510 non-IDMs matched 1:3 for gestational age, race, and year of delivery. Forty-five percent of IDMs had macrosomia compared with 8% of control infants (p = 0.001), and 19% of IDMs had disproportionate macrosomia compared with 1% of control infants (p = 0.001). The rates of hyperbilirubinemia (p = 0.02), hypoglycemia (p = 0.01), and acidosis (p = 0.01) were greatest in infants with disproportionate macrosomia and least in nonmacrosomic infants. The incidence of polycythemia was not significantly different between the groups. We suggest that disproportionate macrosomia in the IDM is associated with an increased likelihood of neonatal complications.

Acidosis↗