Changes in serial blood lead levels during pregnancy.

The first step in modeling lead kinetics during pregnancy includes a description of sequential maternal blood lead (PbB) during pregnancy and the factors controlling it. We analyzed PbB of 105 women living in the Valley of Mexico from week 12 to week 36 of pregnancy and again at parturition. We also used data from all women contributing blood at any stage of pregnancy to determine antecedents of PbB. Pregnancies were uneventful, and offspring were normal. Although geometric mean PbB level averaged around 7.0 micrograms/dl (0.34 mumol/l), with a range of 1.0-35.5 micrograms/dl throughout pregnancy, analysis of variance revealed a significant decrease in mean PbB from week 12 to week 20 (1.1 micrograms/dl) and various significant increases in mean PbB from week 20 to parturition (1.6 micrograms/dl). Regression analyses confirmed the positive linear PbB trend from 20 weeks to parturition and additional contributions of dietary calcium, reproductive history, lifetime residence of Mexico City, coffee drinking, and use of indigenous lead-glazed pottery. Although decreasing hematocrit has been suggested to explain first-half pregnancy PbB decrease, the time course of hematocrit decrease in the present study did not match the sequential changes in PbB. While hemodilution and organ growth in the first half of pregnancy may account for much of the PbB decrease seen between 12 and 20 weeks, the remaining hemodilution and accelerated organ growth of the last half of pregnancy do not predict the trend toward increasing maternal PbB concentration from 20 weeks to delivery. Mobilization of bone lead, increased gut absorption, and increased retention of lead may explain part of the upward PbB trend in the second half of pregnancy. Reduction of lifetime lead exposure may be required to decrease risk of fetal exposure.

Premature ovarian failure and hypothyroidism associated with sicca syndrome.

Two cases of premature ovarian failure, hypothyroidism, and sicca syndrome are described. To our knowledge, this association of sicca syndrome and multiglandular deficiency has not been previously reported. The finding of specific organ antibodies, as well as antibodies to nonorgan antigens in the 2 cases studied, supports the hypothesis that these rare clinical conditions may share a common autoimmune pathogenesis.

Collagen metabolism in premature rupture of amniotic membranes.

Collagen content, acid-soluble collagen, degradation activity, and collagen biosynthesis were measured in 22 normal and 20 prematurely ruptured membranes from pregnancies near term (37 weeks or more). Although no significant differences were found in the collagen content, a clear correlation was found between this value and the interval from premature rupture to delivery. Collagenolytic activity and collagen solubility were higher and collagen synthesis was lower in amniotic membranes that ruptured prematurely. These studies suggest that premature rupture of membranes is associated with extensive changes in collagen metabolism.

Maternal influences on cord blood lead levels.

We constructed models of umbilical cord blood lead (PbB), with and without the addition of maternal PbB at delivery and earlier in pregnancy, to determine which factors explaining cord PbB depended upon maternal PbB and which did not. We prospectively studied women of low-to-middle socioeconomic status who lived in the Valley of Mexico from 12 weeks of pregnancy to delivery. We measured maternal venous PbB during pregnancy and at delivery, and umbilical cord PbB (1-38 micrograms/dl, 0.05-1.83 mumol/l). We used multiple regression analyses to model cord PbB and a logit analysis to model the maternal-cord PbB relationship. Older mothers using lead-glazed pottery and canned foods delivered babies with increased cord PbB, while those with occasional alcohol use during pregnancy, high milk intake, and more spontaneous abortions delivered babies with lower cord PbB. Maternal PbB at 36 weeks of pregnancy and at delivery independently explained additional variance in cord PbB, but maternal PbB earlier in pregnancy did not. Some of the effects of lead-glazed pottery, maternal abortions, alcohol use, and canned food use on cord PbB were mediated through maternal PbB. The effects of maternal age and milk intake on cord PbB were independent of their influence on maternal PbB near delivery. Cord PbBs were higher than maternal PbBs at delivery in 33% of the cases, and were predominant in mothers over 30 and those drinking milk less than once per day. Measurable influence of maternal PbB on delivery cord PbB is limited to the four to eight weeks prior to delivery. Many factors suspected of influencing bone lead also control cord PbB, some of them independently of their effect on maternal delivery PbB. Minimizing fetal exposure near the end of pregnancy may require long-term control of maternal lead exposure and good management of pregnancy and diet.

Prenatal and perinatal lead exposures alter acoustic cry parameters of neonate.

We performed acoustic analyses on cries elicited from a subset of healthy babies born to the Mexico City Prospective Lead Study at 2 days (n = 75), 15 days (n = 176), and 30 days (n = 166). Lead was measured in maternal blood every 8 weeks during pregnancy from week 12 to delivery and in umbilical cord (1-38 micrograms/dL, 0.05-1.84 mumol/L). Percent nasalization and number of cries decreased in babies born to mothers with higher lead levels in the last two trimesters while median fundamental frequency increased in babies born to mothers with higher lead at 12 weeks of pregnancy, and with higher cord lead in multiple regression analysis. Decreased percent nasalization was related to increased brainstem auditory evoked response latencies and interpeak intervals in a subset of the sample. The results suggest an effect of gestational exposure to lead on apparatus innervated by cranial nerves and/or lead effect on cry mediated by lead-altered auditory function. Altered baby cry and auditory function associated with lead might contribute to developmental delays by affecting early communication between caretaker and baby.

Umbilical cord beta-endorphin and early childhood motor development.

Stress during delivery has been associated with elevated umbilical cord plasma beta-endorphin levels. Published research suggests that much cord beta-endorphin originates from fetal pituitary. Intact pituitary function is required for normal growth and development. Relationships between cord beta-endorphin and child development have not been previously reported. We measured paired maternal and cord plasma beta-endorphin concentration in a set of 106 low risk deliveries by solid phase two-site immunoradiometric assay. Geometric mean maternal and cord beta-endorphin concentrations were 128 pg/ml and 196 pg/ml, respectively, with corresponding ranges of 33-533 pg/ml and 70-579 pg/ml. Cord beta-endorphin concentration was significantly higher than maternal, regardless of delivery mode, and the two were significantly correlated (r = 0.231; P = 0.017). Multiple regression modeling showed that forceps delivery, maternal beta-endorphin concentration, bradycardia, vaginal delivery, and birth weight each made independent contributions to elevated cord beta-endorphin. Depressed cord beta-endorphin predicted more day 2 neurological soft signs, lower 6-month mental development, and lower 36-month motor score on psychometric tests of the children. Poorer fine motor control and coordination were predominantly associated with lower beta-endorphin. Level of cord beta-endorphin independent of delivery stress exerted the primary influence upon child motor development. Higher levels of stress-independent beta-endorphin may play a direct role in motor development.

Studies on maternal mortality in Mexico.

The sociocultural, psychological, and medical effects of maternal death are described and analyzed for the purpose of appraising the value of the given death as a measure of the quality of medical care. The work of the Maternal Mortality Committee of the Hospital de Gineco-Obstetetricia No. 1 of the Mexican Social Security Institute over its three years of operation and some results on responsiblity for death and its possible predictabilty are presented. The results show that it is necessary to broaden the Committee's functions in a social, professional, and institutional context so that the indicated factors may be objectively assessed and also that the Committee be transformed into a dynamic organism that will contribute to solving the problem. Recommendations for the operation of the Maternal Mortality Committees are given.

Secular trend in blood lead levels in a cohort of Mexico City children.

We determined the secular trend in blood lead levels in a cohort of 104 children born in Mexico City between 1987 and 1993. We grouped children by the calendar year in which they reached 6 mo of age and measured blood lead levels every 6 mo until they attained 36 mo of age. The overall geometric mean blood lead level was 9.6 microg/dl (range = 1.5-59.5 microg/dl). A repeated measures analysis of variance revealed a highly significant linear trend in blood lead level with year (p < .001); there was a maximum decrease of 7.6 microg/dl between 1989 and 1993. There was a highly significant quadratic age effect (p < .001); blood lead levels rose between 6 and 18 mo of age and decreased thereafter. There was a marginally significant interaction between age of the child and year. Family use of lead-glazed pottery significantly elevated blood lead levels (p = .028). The downward trend in blood lead levels during the time period of study corresponded to the reduction in various sources of lead exposure.

Relationship of maternal, fetal, and amniotic fluid prolactin levels.

Serum prolactin (PRL) was measured by radioimmunoassay in 80 women in serum and amniotic fluid during various stages of normal pregnancy and at delivery. In addition, prolactin levels were measured in cord sera at 60 newborns. PRL levels in maternal serum progressively increased during pregnancy, and they were lower than the corresponding levels in amniotic fluid. A relative decline in the amniotic fluid prolactin between the 39th and the 40th week of gestation was observed. The mean concentration of PRL in umbilical blood was significant lower than that in maternal blood at delivery. The lack of correlation between the PRL in amniotic fluid and the levels found in maternal and newborns serum suggests an independient source of PRL in each of the three compartments.

[Fetal ventriculogram in rhesus immunization. Various aspects]. / Ventriculogramme foetal dans les immunisations rhésus. Quelques aspects

We considered it useful to attempt to diagnose fetal distress or fetal heart failure in hydropic fetuses using external electrodes with a feto-maternal electrocardiographic machine. The pathological tracings that we obtained have been compared with tracings from a normal pregnancy. The authors have not been able to find that there is a significant difference between the electric axes of normal fetuses and pathological fetuses. In fact in both groups we have found as many normal axes with right deviation as with left deviation. In any case we have found that low voltage ventriculograms with a triangular shape have been more common in hydropic fetuses than in the control group. We do not think that this method will be of any use in diagnosing chronic fetal distress of heart failure. All the same we think that we should devote our attention particularly to those patients that have low voltage ventriculograms of triangular shape. We would like to thank Dr Mario Villamichel for his advice and commentary on the manuscript as well as Dr Luis Senties, the Chef de Service of the Department of Isoimmunisation.

[External fetal electrocardiography, the maternal effort test and the oxytocin challenge in cases of fetomaternal rhesus isoimmunisation (author's transl)]. / ECG foetal par voie externe, test d'effort maternal et test à l'ocytocine en cas d'isoimmunisation foeto-maternelle rhésus.

The authors present seven pregnant patients with Rh immunisation. Four of them were of mild degree and three were severely inmunised. All of them had an exercise tolerance test as well as an oxytocin test to evaluate the fetal response to maternal exercise and uterine contractility. The classification utilized for evaluating the fetal response to exercise and its clinical implications are presented. It is concluded that the exercise test is of diagnostic and prognostic value regarding chronic distress during pregnancy and the oxytocin test may help to decide wether the fetus will tolerate the uterine contractions of parturition, and if surgical intervention might be contemplated if during a monitorized labor severe fetal heart changes occur.

[Reliability of the pre-labor weight as a reference mark]. / Confiabilidad del peso pregestacional como dato referido.

Total weight gain during pregnancy has been an anthropometric mean associated with the birth condition. Based on the fact that it is impossible to evaluate every woman in the pregestational period, the referred pregestational weight at week 30 has been evaluated. Such validation was done, comparing the weight gain of a group of women that referred their pregestational weight, with another group who had both weights evaluated. The results suggest, that the women studied, knew and referred correctly the data.

[The intracellular increase of ionized calcium depends on factors present in the blood of patient with preeclampsia]. / El aumento del calcio ionizado intracelular depende de algún factor presente en el suero de las pacientes preeclámpticas.

In previous works our group has demonstrated that intracellular concentration of calcium ionized is greater in patients with pre-eclampsia than in normotense pregnant patients, and that these figures correlate with arterial pressure. Both indicators become normal six weeks after delivery. With the idea of searching the possible participation of soluble factors in the plasma, in increasing free, intracellular calcium, eight pre-eclamptic patients, were studied; the patients were diagnosed by the criteria of the American College of Gynecologists and Obstetricians. As a control group, eight normotense pregnant patients, were included; they were paired by age, chronological and gestational. To measure transmembrane calcium flow, platelets from healthy males, were used. The platelets were incubated during 0, 15, 30 and 60 minutes in sera of pre-eclamptic patients, or of normotensive pregnant patients, marked with Ca. The differences in calcium transportation, were evaluated with variance analysis of Kruskall Wallis. Calcium transportation was greater when the platelets were incubated in pre-eclamptic patients sera, Md = 1.475 +/- 0.311 nanomoles than when were incubated in normotensive women sera, Md = 0.9725 +/- 0.58 nanomoles, p < 0.02. This finding suggests that in pre-eclamptic patients serum, exists some factor that facilitates the entrance of calcium to the cell, that provokes an increase in free calcium concentration, and it participates in the gestational hypertension.

[Diagnosis and treatment of the male factor in the age of intracytoplasmic sperm injection]. / El diagnóstico y tratamiento del factor masculino en la era del ICSI.

Currently, we are witnesses of the Assisted Reproductive techniques; advances reproductive goals have been reached with the Intracytoplasmic Sperm Injection (ICSI) in patients with male factor. However, micromanipulation techniques allowed the reproductive solution without an etiologic and/or physiopathologic diagnosis. The andrologic workup of the dynamic and functional sperm characteristics with the endocrine and urologic evaluation should be performed into the infertility management.

[Socioeconomic factors in high risk pregnancy]. / Factores socioeconómicos en el embarazo de alto riesgo.

PIP: The study of high risk during pregnancy was undertaken to show the most viable ways for solving those problems affecting maternal-fetal morbidity and mortality. The authors are hopeful that in the future, the 2 branches of medicine, perinatology and obstetrics, will no longer differentiate between high risk for mother and fetus or neonate but will direct attention to what is high risk for 1 society in particular. These professionals will undertake an interdisciplinary approach of the problem to benefit society. (author's)^ieng

[Assessment of the penetration of culture media in uterine cavity as an effect of cervical lavage before embryo transfer: prospective and observational study of samples obtained in hysterectomy]. / Evaluación de la penetración del medio de cultivo a la cavidad uterina como efecto del lavado cervical previo a la transferencia embrionaria: estudio prospectivo y observacional en piezas obtenidas por histerectomía.

Cervical lavage used to remove and cleaning some of the scale elements as well as cervical mucous during embryo transfer has been a regular practice in many reproductive centers worldwide. However, the microenvironment influence using these techniques will or not be detrimental in the embryo development. Under this issue, a prospective study was doing in 16 patients (underwent hysterectomy). A cervical lavage was performed previous to the procedure similar to the embryo's transfer step, subsequently cervical invasion was checking. The age was 36.4 +/- 8.6 years, preoperatory diagnosis was abnormal uterine bleeding (n = 4), myomata (n = 4), adenomiosis (n = 4), endometrial polyp (n = 3) and chronic pelvic pain (n = 1). Uterine weight was 127.5 +/- 55.4 g with a surgical time of 48.8 +/- 12.5 minutes. Medium in the uterine cavity was founded in only one case. We believe that cervical lavage is a secure technique in embryo transfer.

[A prospective randomized trial of the impact of misoprostol (PgE1) on pregnancy rate after intrauterine insemination (IUI) therapy: a preliminary report]. / Estudio prospectivo y aleatorio del impacto de misoprostol (PgE1) en las tasas de embarazo con inseminación intrauterina (IIU): informe preliminar.

Although the use of prostaglandin plays an important role in the reproductive human physiology, it is still controversial in the reproductive field. Ovarian stimulation as well as intrauterine insemination increased the reproductive goals in certain group of patients. The objective of the present study was to evaluate the prostaglandin effect (misoprostol) in patients under ovarian stimulation and intrauterine insemination and their final outcome in the clinical pregnancy rate. There were a total of 59 ovarian stimulated cycles, the study group (n = 29) received 200 micrograms of prostaglandin E1 (misoprostol) intravaginal after IUI, compared with the control group (n = 30). Demographic characteristics were similar in both groups. There were no differences in age, FSH. LH and E2, hCG day and number of ampoules between groups. However, a significant pregnancy rate was observed between groups (31% study group vs. 20% control group). We concluded that prostaglandin application in stimulated cycles under intrauterine insemination remain a beneficial effect showing in the pregnancy outcome.

[Risk factors for changes in glucose metabolism in pregnancy]. / Factores de riesgo para alteración en el metabolismo de la glucosa durante la gestación.

Eighty women were studied having between 20-25 weeks of gestation at the National Institute of Perinatology. Weight and height were taken, and they were questioned about the risk factors (positive family history of diabetes mellitus, age, overweight and number of gestations). Two hours postprandial glucose tests were carried out using 100 g glucose load. Plasma glucose values were determinated according to the glucose-oxidase technique. Results showed that 36% of the population had at least glucose metabolism alteration (GMA) (glucose value 120 mg/dL). No significant difference was found for the weeks of gestation, nor number of gestations to define any cut point. On the other hand, significant values were found for the other risk factors, such as being 35 years or older, having 119% and 103% or more of pregestational and gestational weight for height respectively and having positive maternal family history of diabetes mellitus. The risk factor that is more capable to identify the subjects with an GMA is age 35 years followed by positive maternal family history of diabetes mellitus; when the combination of 4 risk factors is observed (gestas factor is excluded because it is a confusion element), the pregestational and pregestational and gestational weights work more like secondary supplementary risk factors than like determinants of the metabolic process. In view of these facts, it was found that positive maternal history of diabetes mellitus and the age less than or equal to 35 years individually and the presence of 3-4 risk factors can be considered high risk characteristics to develop GMA.

[Importance of free intracellular calcium in the physiopathology of pre-eclampsia]. / Importancia del calcio libre intracelular en la fisiopatología de la preeclampsia.

Due to the participation of intracellular free calcium in the mechanisms of vascular smooth muscle contraction, and its importance in the physiopathology of essential arterial hypertension, its possible role in pre-eclampsia physiopathology, was investigated as a cellular model, platelets, were use, as they are similar to vascular smooth muscle cells. The study purpose was to investigate if intracellular concentration of ionized calcium is greater in the patients with pre-eclampsia than in normotensive pregnant women, and also, if there exists a correlation between intracellular calcium concentrations and arterial tension, Seven pre-eclamptic patients, diagnosed by the following criteria: arterial tension greater than or equal to 130/90 mmHg, edema and proteinuria, between 20 to 35 years of age, during the third trimester of gestation, without personal nor family antecedents of hypertension; none of them received treatment at the time, were studied. As control group seven normotensive pregnant women, equal by chronologic and gestational age, were included. Intracellular calcium in platelets was measured by Fluo-3-Am, and arterial blood pressure with conventional sphygmomanometer. Intracellular calcium and arterial blood pressure values, were compared, in both groups by Student's t, and analysis of lineal regression between intracellular calcium and mean arterial blood pressure, was done. Intracellular calcium was significantly greater in patients with pre-eclampsia, than the ones in the control group (142 +/- 5.6 vs 110 +/- 14 p less than 0.0001). Mean arterial blood pressure was also significantly greater in patients with pre-eclampsia (114 +/- 5 vs 83 +/- 3 p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Influence of intrafollicular factors at ovarian level during oocyte/embryo development]. / Influencia de los factores intrafoliculares a nivel ovárico durante el desarrollo óvulo/embrionario.

There is series of factors associated to fertilization and embryo development events. Each factor has a role in the inter-relationship between various molecular events related to oocyte/embryo quality. Dynamic features associated to endocrine-paracrine environment are determinant to the role of each factor in ovaric follicullar development. Growth factors, vascular-endothelial growth factor, nitric oxide, leptin and others correlate in ovular maturity process. That is why growth factors, vascular-endothelial growth factor, nitric oxide, leptin and others can be expressed as embryo viability and implantation biomarkers.