Ante el reto que enfrentan las universidades con respecto al trabajo que deben adelantar tanto en... more Ante el reto que enfrentan las universidades con respecto al trabajo que deben adelantar tanto en la formación de investigadores como en la generación de conocimiento derivado de la investigación y su posterior articulación con el sector productivo y con el desarrollo de las políticas estatales, en el presente artículo se analiza el papel de la investigación, se caracterizan sus diferentes figuras y se presenta una reflexión sobre la manera como la Fundación Universitaria Colombo Internacional -UNICOLOMBO- ha estructurado la formación investigativa con la Empresa y el Estado en una contextualización de los procesos universitario.
Ascertaining the timing of the peopling of Europe, after the first out-of-Africa demographic expa... more Ascertaining the timing of the peopling of Europe, after the first out-of-Africa demographic expansion at the end of the Pliocene, is of great interest to paleoanthropologists. One of the earliest direct evidences for fossil hominins in western Europe comes from an infilled karstic cave site called Gran Dolina at Atapuerca, in a stratum w1.5 m below the Brunhes-Matuyama (B-M) geomagnetic boundary (780 ka) within lithostratigraphic unit TD6. However, most of the meters of fossil-and tool-bearing strata at Gran Dolina have been difficult to date. Therefore, we applied both thermoluminescence (TL) and infraredstimulated-luminescence (IRSL) multi-aliquot dating methods to fine-silt fractions from sediment samples within Gran Dolina and the nearby Galería cave site. We also applied these methods to samples from the present-day surface soils on the surrounding limestone hill slopes to test the luminescenceclock-zeroing-by-daylight assumption. Within the uppermost 4 m of the cave deposits at Gran Dolina, TL and paired TL and IRSL ages range stratigraphically from 198 AE 19 ka to 244 AE 26 ka. Throughout Gran Dolina, all luminescence results are stratigraphically self-consistent and, excepting results from two stratigraphic units, are consistent with prior ESR-U-series ages from progressively deeper strata. Thermoluminescence ages culminate at 960 AE 120 ka approximately 1 m below the 780 ka B-M boundary. At Galería, with one exception, TL and IRSL ages range stratigraphically downward from 185 AE 26 ka to 503 AE 95 ka at the base of the lowermost surface-inwash facies. These results indicate that TL and (sometimes) IRSL are useful dating tools for karstic inwash sediments older than ca. 100 ka, and that a more accurate chronostratigraphic correlation is now possible among the main Atapuerca sites (Gran Dolina, Galería, Sima de los Huesos). Furthermore, the oldest TL age of ca. 960 ka from Gran Dolina, consistent with biostratigraphic and paleomagnetic evidence, implies a probable numeric age of 900-950 ka for the oldest hominin remains (w0.8 m below the TL sample). This age window suggests a correspondence to Marine Isotope Stage (MIS) 25, a relatively warm and humid interglaciation.
Page 1. MANAGEMENT OF NORMAL PREGNANCY, LABOR AND PUERPERIUM 309 probably provides oxytocic stimu... more Page 1. MANAGEMENT OF NORMAL PREGNANCY, LABOR AND PUERPERIUM 309 probably provides oxytocic stimulation of uterine contractions. The mechanism of action of oxytocin generated by the fetus is not known. ...
Advanced location based services have the ability to track users with Global Positioning System (... more Advanced location based services have the ability to track users with Global Positioning System (GPS)-enabled cell phones in real-time. These applications share a common problem; the continuous calculation and transmission of GPS fixes from the mobile phone to a server consumes a considerable amount of energy and increases data transmission costs. Therefore, an application-level algorithm is necessary to reduce the number of GPS fixes calculated and transmitted, while continuing to track the user in real-time and record an accurate representation of his or her travel path. In this paper, two complementary algorithms are presented: the Critical Point (CP) algorithm, which filters data points to be transmitted to the server, and the location-aware state machine, which dynamically manages the frequency of the location re-calculation update rate. Both algorithms were implemented in TRAC-IT, a Java Micro Edition (Java ME) application designed to automatically collect user travel behavior; the proposed algorithms allow TRAC-IT to build an accurate representation of the user's path with a considerably reduced number of fixes while significantly extending mobile device battery life.
The purpose of this study was to determine prospectively whether unplanned pregnancies are associ... more The purpose of this study was to determine prospectively whether unplanned pregnancies are associated with adverse pregnancy outcomes among users of natural family planning. Women who became pregnant while using natural family planning were identified in five centers worldwide: there were 373 unplanned and 367 planned pregnancies in this cohort. The subjects were followed up at 16 and 32 weeks' gestation and after delivery. The risks of spontaneous abortion, low birth-weight, and preterm birth were estimated after adjustment by logistic regression. The women with unplanned pregnancies were more likely to be at the extremes of age, to report more medical problems before and during the index pregnancy, and to seek antenatal care later in gestation than the women with planned pregnancies. However, women with planned pregnancies reported a higher rate of spontaneous abortion in previous pregnancies (28.8%) than did women with unplanned pregnancies (12.9%). There were no significant differences in the rates of spontaneous abortion, low birthweight, or preterm birth between the two groups. No increased risk of adverse pregnancy outcomes was observed among women who experienced an unplanned pregnancy while using natural family planning.
This study assessed reported changes in clinical breastfeeding support practices following a thre... more This study assessed reported changes in clinical breastfeeding support practices following a three-day (approximately 24 hour) course. The course, presented at the Catholic University in Santiago, Chile, included the physiology of lactation and lactational infertility, related policy, clinical skills, the Lactational Amenorrhea Method (LAM), and program-related findings. A questionnaire was sent to all participants and an additional systematic sample was telephoned to assure a statistically valid sample. Sixty-nine percent of respondents reported changes in clinical practices resulting from attendance at the course. The results support the concept, now being advanced by the Baby-Friendly Hospital Initiative, that an 18-24 hour course can change clinical practices. JHL 11: 185-190, 1995. and to successfully implement that choice, through changes in clinical and hospital practices. 185
A control/intervention study carried out in Santiago, Chile assessed the impact of five intervent... more A control/intervention study carried out in Santiago, Chile assessed the impact of five interventions on breastfeeding patterns and duration, and demonstrated a significant increase in full breastfeeding a t six months (32 percent to 67 percent). Fifty-nine of 422 post-intervention women were included in a sixth intervention: prenatal group educational sessions emphasizing the skills necessary to initiate and maintain breastfeeding past the neonatal period. A significantly higher percentage of this subset of women were fully breastfeeding at six months compared to those who received only the five basic interventions (80 percent and 65 percent, respectively). The effect was greater among primiparous women. We conclude that prenatal group education with hands-on skills reinforcement is a significant and additive component of breastfeeding support, especially among those who have no previous breastfeeding experience. JHL 1215JHL -19, 1996
It is well accepted that breasteeding contributes significantly to child survival and child nutri... more It is well accepted that breasteeding contributes significantly to child survival and child nutrition. Healthful child spacing is associated with improved birth outcomes and maternal recovery. On a population basis, breastfeeding may contribute more to birth spacing than all family planning use combined in many countries. However, while breastfeeding does provide a period of infertility, until recently, there was no reliable way for an individual woman to capitalize on this lactational infertility for her own efficatious child spacing. The Lactational Amenorrhea Method (LAM) is a new introductory family planning method that simultaneously promotes child spacing and breastfeeding, with its optimal nutrition and disease preventive benefits for the infant. LAM, as it is called, is based on the utilization of lactational infertility for protection from pregnancy and indicates the time for the introduction of a complementary family planning method. LAM is recommended for up to six months postpartum for women who are fully or nearly fully breastfeeding and amenorrheic, and relies on the maintenance of appropriate brastfeeding practices to prolong lactational infertility, with the concomitant delay in menses return. A recent clinical trial confirmed the theoretical 98% or higher effectiveness of the method and field trials are demonstrating its aceptability. Nonetheless, some demographers and family planning organizations continue to debate its value. The development, efficacy, and sequelae of the method are presented using data from several studies by the authors. C'est un fait reconnu que l'allaitement naturel par la mère contribue de façon significative à la survie du nourrisson et à sa nutrition. L'espacement des naissances est associé à des accouchements et des retours de couches plus satisfaisants. Au niveau de la populations, l'allaitement au sein contribue sans doute davantage à l'espacement des naissances que toutes les autres méthodes de planning familial réunies. Il n'en reste pas moins que, si l'allaitement occasionne une période de stérilité, la femme n'avait jusqu'ici acun moyen fiabel de tourner à son avatae cte stérilité du temps de lactation pour espacer efficacement les naissances. La méthode de l'aménorrhée de la lactation (MAL) est une méthode de planning familial nouvellment introduite qui favorise simultanéument l'espacement des naissances et l'allaitement au sein, tout en assurant des conditions optimales de nutrition et la prévention de maladies pour l'enfant. Cette méthode fait appel à la stérilité de la lactation comme protection contre une nouvelle grossesse et permet de déceler le moment où il devient nécessaire de penser à une méthode supplémentaire de contaception. Il est recommandé aux femmes d'avoir recours à la MAL jusqu'à six mois après l'accouchement, tant qu'uelles allaitent entièrement, ou presque, et que les règles n'ont pas répparu. Cette méthode table sur la poursuite de l'allaitement pour prolonger la stérilité de la lactation et retarder le retour des menstruations. Une récente étude clinique a confirmé l'efficacité théorique à 98%, voire plus, de cette méthode et les essaid dans la population en démontrent l'acceptabilité. Néanmoins. certains démographes et certaines organisations de planning familial continuent d'en débattre la valuer. Le développement, l'utilité et les séqualles de cette méthode sont présentés en s'appuyant sur les résultats de pluisierrs études effectuées par les auteurs. Se acepta en general que el ammantamiento contribuye significantivamente a la superiviencia y nutrición de los niños. El espaciamente sano de los niños se asocia con mejores resultados de los nacimienetos y la recuperación materna. Tomando una base demográfica, es posible que el amamantamiento contribuya má al espaciamiento de los nacimientos que todo el uso combinado de la planificación familiar. Sin embargo, si bien el amamantamiento proporciona un período de infecundidad, hsta hace poco no había una forma segura que permitiera a las mujeres aprovechar esta infecundiada por amamantamiento para realizar su propio espaciamiento eficaz de los nacimientos. El Método de Amenorrea por Lactancia (LAM) es un nuevo método introductorio de la plaificación familiar que promueve similtáneamente el escpaciamiento de los nacimientos y el amamantamineto, con sus beneficios óptimos de nutrición y prvención de enfermedades prar el niño. El LAM se basa en la tulización de la infecundidad por lactancia como prevención del embarazo e indica el momento de introducción de un método complementario de planificación familiar. El LAM se recomienda durante un período máximo de seis meses con posterioridad al parto para las mujeres que amamantan plenamente o casi plenamente y están en amenorrea, y depende del mantenimiento de prácticas apropiadas de amamantamiento para prologar la infecundidad por lactancia, con la demora concomitante en le retorno de la menstruación. Un ensayo clínico reciente confirmó la eficacia teórica del 98% o superior del método y los ensayos de campo están demostrando su aceptabilida. Sin embargo, algunos demógrafos y organizaciones de planificación familiar continúan debatiendo su valor. Se presenta el desarrollo, la eficacia y las secuelas del método utilizando datos de diversos estudios de los autores.
American Journal of Obstetrics and Gynecology, 1995
Our purpose was to ascertain the effects of timing of conception on the risk of spontaneous abort... more Our purpose was to ascertain the effects of timing of conception on the risk of spontaneous abortion. To assess these effects, women who conceived while using natural family planning were identified in five centers worldwide between 1987 and 1993. Timing of conception was determined from 868 natural family planning charts that recorded day of intercourse and indices of ovulation (cervical mucus peak obtained according to the ovulation method and/or basal body temperature). Conceptions on days - 1 or 0 with respect to the natural family planning estimated day of ovulation were considered to be "optimally timed," and all other conceptions were considered as "non-optimally timed." The rate of spontaneous abortions per 100 pregnancies was examined in relation to timing of conception, ages, reproductive history, and other covariates with bivariate and multivariate statistical methods. There were 88 spontaneous abortions among 868 pregnancies (10.1%). The spontaneous abortion rate was similar for 361 optimally timed conceptions (9.1%) and 507 non-optimally timed conceptions (10.9%). However, among 171 women who had experienced a spontaneous abortion in a prior pregnancy, the rate of spontaneous abortion in the index pregnancy was significantly higher with non-optimally timed conceptions (22.6%) as compared with optimally timed conceptions (7.3%). This association was not observed among 697 women with no history of pregnancy loss. The adjusted relative risk of spontaneous abortion among women with non-optimally timed conceptions and a history of pregnancy loss was 2.35 (95% confidence intervals 1.42 to 3.89). The excess risk of spontaneous abortion was observed with both preovulatory and postovulatory conceptions. Overall, there is no excess risk of spontaneous abortion among the pregnancies conceived during natural family planning use. However, among women with a history of pregnancy loss, there is an increased risk of spontaneous abortion associated with preovulatory or postovulatory delayed conceptions.
Se reconoce que el espíritu investigativo debería ser un aspecto importante del qué hacer académi... more Se reconoce que el espíritu investigativo debería ser un aspecto importante del qué hacer académico tanto de los estudiantes como de los docentes. No obstante, se observa que existe una especie de adormecimiento de tal espíritu, debido principalmente a la falta de motivación y al desenfoque que se tiene de la investigación.
Ante el reto que enfrentan las universidades con respecto al trabajo que deben adelantar tanto en... more Ante el reto que enfrentan las universidades con respecto al trabajo que deben adelantar tanto en la formación de investigadores como en la generación de conocimiento derivado de la investigación y su posterior articulación con el sector productivo y con el desarrollo de las políticas estatales, en el presente artículo se analiza el papel de la investigación, se caracterizan sus diferentes figuras y se presenta una reflexión sobre la manera como la Fundación Universitaria Colombo Internacional -UNICOLOMBO- ha estructurado la formación investigativa con la Empresa y el Estado en una contextualización de los procesos universitario.
Ascertaining the timing of the peopling of Europe, after the first out-of-Africa demographic expa... more Ascertaining the timing of the peopling of Europe, after the first out-of-Africa demographic expansion at the end of the Pliocene, is of great interest to paleoanthropologists. One of the earliest direct evidences for fossil hominins in western Europe comes from an infilled karstic cave site called Gran Dolina at Atapuerca, in a stratum w1.5 m below the Brunhes-Matuyama (B-M) geomagnetic boundary (780 ka) within lithostratigraphic unit TD6. However, most of the meters of fossil-and tool-bearing strata at Gran Dolina have been difficult to date. Therefore, we applied both thermoluminescence (TL) and infraredstimulated-luminescence (IRSL) multi-aliquot dating methods to fine-silt fractions from sediment samples within Gran Dolina and the nearby Galería cave site. We also applied these methods to samples from the present-day surface soils on the surrounding limestone hill slopes to test the luminescenceclock-zeroing-by-daylight assumption. Within the uppermost 4 m of the cave deposits at Gran Dolina, TL and paired TL and IRSL ages range stratigraphically from 198 AE 19 ka to 244 AE 26 ka. Throughout Gran Dolina, all luminescence results are stratigraphically self-consistent and, excepting results from two stratigraphic units, are consistent with prior ESR-U-series ages from progressively deeper strata. Thermoluminescence ages culminate at 960 AE 120 ka approximately 1 m below the 780 ka B-M boundary. At Galería, with one exception, TL and IRSL ages range stratigraphically downward from 185 AE 26 ka to 503 AE 95 ka at the base of the lowermost surface-inwash facies. These results indicate that TL and (sometimes) IRSL are useful dating tools for karstic inwash sediments older than ca. 100 ka, and that a more accurate chronostratigraphic correlation is now possible among the main Atapuerca sites (Gran Dolina, Galería, Sima de los Huesos). Furthermore, the oldest TL age of ca. 960 ka from Gran Dolina, consistent with biostratigraphic and paleomagnetic evidence, implies a probable numeric age of 900-950 ka for the oldest hominin remains (w0.8 m below the TL sample). This age window suggests a correspondence to Marine Isotope Stage (MIS) 25, a relatively warm and humid interglaciation.
Page 1. MANAGEMENT OF NORMAL PREGNANCY, LABOR AND PUERPERIUM 309 probably provides oxytocic stimu... more Page 1. MANAGEMENT OF NORMAL PREGNANCY, LABOR AND PUERPERIUM 309 probably provides oxytocic stimulation of uterine contractions. The mechanism of action of oxytocin generated by the fetus is not known. ...
Advanced location based services have the ability to track users with Global Positioning System (... more Advanced location based services have the ability to track users with Global Positioning System (GPS)-enabled cell phones in real-time. These applications share a common problem; the continuous calculation and transmission of GPS fixes from the mobile phone to a server consumes a considerable amount of energy and increases data transmission costs. Therefore, an application-level algorithm is necessary to reduce the number of GPS fixes calculated and transmitted, while continuing to track the user in real-time and record an accurate representation of his or her travel path. In this paper, two complementary algorithms are presented: the Critical Point (CP) algorithm, which filters data points to be transmitted to the server, and the location-aware state machine, which dynamically manages the frequency of the location re-calculation update rate. Both algorithms were implemented in TRAC-IT, a Java Micro Edition (Java ME) application designed to automatically collect user travel behavior; the proposed algorithms allow TRAC-IT to build an accurate representation of the user's path with a considerably reduced number of fixes while significantly extending mobile device battery life.
The purpose of this study was to determine prospectively whether unplanned pregnancies are associ... more The purpose of this study was to determine prospectively whether unplanned pregnancies are associated with adverse pregnancy outcomes among users of natural family planning. Women who became pregnant while using natural family planning were identified in five centers worldwide: there were 373 unplanned and 367 planned pregnancies in this cohort. The subjects were followed up at 16 and 32 weeks' gestation and after delivery. The risks of spontaneous abortion, low birth-weight, and preterm birth were estimated after adjustment by logistic regression. The women with unplanned pregnancies were more likely to be at the extremes of age, to report more medical problems before and during the index pregnancy, and to seek antenatal care later in gestation than the women with planned pregnancies. However, women with planned pregnancies reported a higher rate of spontaneous abortion in previous pregnancies (28.8%) than did women with unplanned pregnancies (12.9%). There were no significant differences in the rates of spontaneous abortion, low birthweight, or preterm birth between the two groups. No increased risk of adverse pregnancy outcomes was observed among women who experienced an unplanned pregnancy while using natural family planning.
This study assessed reported changes in clinical breastfeeding support practices following a thre... more This study assessed reported changes in clinical breastfeeding support practices following a three-day (approximately 24 hour) course. The course, presented at the Catholic University in Santiago, Chile, included the physiology of lactation and lactational infertility, related policy, clinical skills, the Lactational Amenorrhea Method (LAM), and program-related findings. A questionnaire was sent to all participants and an additional systematic sample was telephoned to assure a statistically valid sample. Sixty-nine percent of respondents reported changes in clinical practices resulting from attendance at the course. The results support the concept, now being advanced by the Baby-Friendly Hospital Initiative, that an 18-24 hour course can change clinical practices. JHL 11: 185-190, 1995. and to successfully implement that choice, through changes in clinical and hospital practices. 185
A control/intervention study carried out in Santiago, Chile assessed the impact of five intervent... more A control/intervention study carried out in Santiago, Chile assessed the impact of five interventions on breastfeeding patterns and duration, and demonstrated a significant increase in full breastfeeding a t six months (32 percent to 67 percent). Fifty-nine of 422 post-intervention women were included in a sixth intervention: prenatal group educational sessions emphasizing the skills necessary to initiate and maintain breastfeeding past the neonatal period. A significantly higher percentage of this subset of women were fully breastfeeding at six months compared to those who received only the five basic interventions (80 percent and 65 percent, respectively). The effect was greater among primiparous women. We conclude that prenatal group education with hands-on skills reinforcement is a significant and additive component of breastfeeding support, especially among those who have no previous breastfeeding experience. JHL 1215JHL -19, 1996
It is well accepted that breasteeding contributes significantly to child survival and child nutri... more It is well accepted that breasteeding contributes significantly to child survival and child nutrition. Healthful child spacing is associated with improved birth outcomes and maternal recovery. On a population basis, breastfeeding may contribute more to birth spacing than all family planning use combined in many countries. However, while breastfeeding does provide a period of infertility, until recently, there was no reliable way for an individual woman to capitalize on this lactational infertility for her own efficatious child spacing. The Lactational Amenorrhea Method (LAM) is a new introductory family planning method that simultaneously promotes child spacing and breastfeeding, with its optimal nutrition and disease preventive benefits for the infant. LAM, as it is called, is based on the utilization of lactational infertility for protection from pregnancy and indicates the time for the introduction of a complementary family planning method. LAM is recommended for up to six months postpartum for women who are fully or nearly fully breastfeeding and amenorrheic, and relies on the maintenance of appropriate brastfeeding practices to prolong lactational infertility, with the concomitant delay in menses return. A recent clinical trial confirmed the theoretical 98% or higher effectiveness of the method and field trials are demonstrating its aceptability. Nonetheless, some demographers and family planning organizations continue to debate its value. The development, efficacy, and sequelae of the method are presented using data from several studies by the authors. C'est un fait reconnu que l'allaitement naturel par la mère contribue de façon significative à la survie du nourrisson et à sa nutrition. L'espacement des naissances est associé à des accouchements et des retours de couches plus satisfaisants. Au niveau de la populations, l'allaitement au sein contribue sans doute davantage à l'espacement des naissances que toutes les autres méthodes de planning familial réunies. Il n'en reste pas moins que, si l'allaitement occasionne une période de stérilité, la femme n'avait jusqu'ici acun moyen fiabel de tourner à son avatae cte stérilité du temps de lactation pour espacer efficacement les naissances. La méthode de l'aménorrhée de la lactation (MAL) est une méthode de planning familial nouvellment introduite qui favorise simultanéument l'espacement des naissances et l'allaitement au sein, tout en assurant des conditions optimales de nutrition et la prévention de maladies pour l'enfant. Cette méthode fait appel à la stérilité de la lactation comme protection contre une nouvelle grossesse et permet de déceler le moment où il devient nécessaire de penser à une méthode supplémentaire de contaception. Il est recommandé aux femmes d'avoir recours à la MAL jusqu'à six mois après l'accouchement, tant qu'uelles allaitent entièrement, ou presque, et que les règles n'ont pas répparu. Cette méthode table sur la poursuite de l'allaitement pour prolonger la stérilité de la lactation et retarder le retour des menstruations. Une récente étude clinique a confirmé l'efficacité théorique à 98%, voire plus, de cette méthode et les essaid dans la population en démontrent l'acceptabilité. Néanmoins. certains démographes et certaines organisations de planning familial continuent d'en débattre la valuer. Le développement, l'utilité et les séqualles de cette méthode sont présentés en s'appuyant sur les résultats de pluisierrs études effectuées par les auteurs. Se acepta en general que el ammantamiento contribuye significantivamente a la superiviencia y nutrición de los niños. El espaciamente sano de los niños se asocia con mejores resultados de los nacimienetos y la recuperación materna. Tomando una base demográfica, es posible que el amamantamiento contribuya má al espaciamiento de los nacimientos que todo el uso combinado de la planificación familiar. Sin embargo, si bien el amamantamiento proporciona un período de infecundidad, hsta hace poco no había una forma segura que permitiera a las mujeres aprovechar esta infecundiada por amamantamiento para realizar su propio espaciamiento eficaz de los nacimientos. El Método de Amenorrea por Lactancia (LAM) es un nuevo método introductorio de la plaificación familiar que promueve similtáneamente el escpaciamiento de los nacimientos y el amamantamineto, con sus beneficios óptimos de nutrición y prvención de enfermedades prar el niño. El LAM se basa en la tulización de la infecundidad por lactancia como prevención del embarazo e indica el momento de introducción de un método complementario de planificación familiar. El LAM se recomienda durante un período máximo de seis meses con posterioridad al parto para las mujeres que amamantan plenamente o casi plenamente y están en amenorrea, y depende del mantenimiento de prácticas apropiadas de amamantamiento para prologar la infecundidad por lactancia, con la demora concomitante en le retorno de la menstruación. Un ensayo clínico reciente confirmó la eficacia teórica del 98% o superior del método y los ensayos de campo están demostrando su aceptabilida. Sin embargo, algunos demógrafos y organizaciones de planificación familiar continúan debatiendo su valor. Se presenta el desarrollo, la eficacia y las secuelas del método utilizando datos de diversos estudios de los autores.
American Journal of Obstetrics and Gynecology, 1995
Our purpose was to ascertain the effects of timing of conception on the risk of spontaneous abort... more Our purpose was to ascertain the effects of timing of conception on the risk of spontaneous abortion. To assess these effects, women who conceived while using natural family planning were identified in five centers worldwide between 1987 and 1993. Timing of conception was determined from 868 natural family planning charts that recorded day of intercourse and indices of ovulation (cervical mucus peak obtained according to the ovulation method and/or basal body temperature). Conceptions on days - 1 or 0 with respect to the natural family planning estimated day of ovulation were considered to be "optimally timed," and all other conceptions were considered as "non-optimally timed." The rate of spontaneous abortions per 100 pregnancies was examined in relation to timing of conception, ages, reproductive history, and other covariates with bivariate and multivariate statistical methods. There were 88 spontaneous abortions among 868 pregnancies (10.1%). The spontaneous abortion rate was similar for 361 optimally timed conceptions (9.1%) and 507 non-optimally timed conceptions (10.9%). However, among 171 women who had experienced a spontaneous abortion in a prior pregnancy, the rate of spontaneous abortion in the index pregnancy was significantly higher with non-optimally timed conceptions (22.6%) as compared with optimally timed conceptions (7.3%). This association was not observed among 697 women with no history of pregnancy loss. The adjusted relative risk of spontaneous abortion among women with non-optimally timed conceptions and a history of pregnancy loss was 2.35 (95% confidence intervals 1.42 to 3.89). The excess risk of spontaneous abortion was observed with both preovulatory and postovulatory conceptions. Overall, there is no excess risk of spontaneous abortion among the pregnancies conceived during natural family planning use. However, among women with a history of pregnancy loss, there is an increased risk of spontaneous abortion associated with preovulatory or postovulatory delayed conceptions.
Se reconoce que el espíritu investigativo debería ser un aspecto importante del qué hacer académi... more Se reconoce que el espíritu investigativo debería ser un aspecto importante del qué hacer académico tanto de los estudiantes como de los docentes. No obstante, se observa que existe una especie de adormecimiento de tal espíritu, debido principalmente a la falta de motivación y al desenfoque que se tiene de la investigación.
Uploads
Papers by Alfredo Perez