Evidence of fertility decline in Karachi.
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Amenorrhea↗
SEARCH · PubMed Health
Results for “Fertility Pattern Method”
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The analysis of linkages in demographic theory.
Many seemingly different questions that arise in the analysis of population change can be phrased as the same technical question: How, within a given demographic model, would variable y change if the age- or time-specific function f were to change arbitrarily in shape and intensity? At present demography lacks the machinery to answer this question in analytical and general form. This paper suggests a method based on modern functional calculus for deriving closed-form expressions for the sensitivity of demographic variables to changes in input functions or schedules. It uses this "linkage method" to obtain closed-form expressions for the response of the intrinsic growth rate, birth rate, and age composition of a stable population to arbitrary marginal changes in its age patterns of fertility and mortality. It uses it also to obtain expressions for the transient response of the age composition of a nonstable population to time-varying changes in the birth sequence, and to age-specific fertility and mortality patterns that change over time. The problem of "bias" in period vital rates is also looked at.
Adult↗
Induced abortions in Denmark.
BACKGROUND: A law on Induced Abortion on Request came into force in Denmark in 1973. During the first years the rate of abortion increased but since the early 1980s the rate has been rather constant. The paper reviews recent findings concerning induced abortion and discusses its role in controlling fertility. METHODS: Trends in induced abortion is described from routine statistics while information on the aborting women are taken both from a survey and from a register based study of fertility- and abortion-pattern among a cohort of women. RESULTS: Fertility trends in Denmark are characterized by an increasing age at first birth. Half of the aborters to day have no children before and 10% had given birth less than 18 months earlier. Among aborters a higher proportion than among parturients were still under education and a higher proportion were single with no steady partner. Half of the aborters became pregnant in spite of contraceptive use, indicating a need for better contraceptives. CONCLUSIONS: Induced abortion has become a generally accepted form of birth control in Denmark and the decision to terminate a pregnancy is influenced by many factors including the woman's conjugal--and educational situation. A strategy for prevention of induced abortion must take into consideration the social circumstances of women and for families with children.
Abortion, Induced↗
Patterns of LHbetacf among women in health and disease.
Urine based gonadotropin assays provide a practical means of analyzing hormone secretion patterns. While research protocols have revealed pulsatile patterns of gonadotropins such as LH in the blood, these assays are of limited clinical use since daily venipuncture sampling is not feasible outside of a research environment. However, collection of several urine samples provides a method to achieve the same visualization of gonadotropin patterns in patients using a convenient and generally applicable technique based on analysis of the highly stable hLHbetacf for monitoring LH and hCGbetacf for monitoring pituitary hCG. We demonstrated that two different sampling techniques for analyzing these gonadotropin metabolites yielded the same information on their excretory patterns, either sampling of spot urines or collecting first morning void urines for several days. Next, we studied the core excretory patterns in several populations: menstruating and postmenopausal women from the general population, and two populations of women from a fertility center, one of which had polycystic ovaries (PCO). The PCO population was also subdivided into those with and without insulin resistance (IR). It was found that our hLHbetacf assay did not measure the form of the LH core (v-hLHbetacf) produced in subjects who were homozygous for a variant form of LH (v-LH). None of our patients tested were homozygous for the variant form of LH. It was also found that in most non-PCO (NPCO) patients, the hLHbetacf peak lasted for 7-9 days while among the PCO patients this peak frequently lasted for less than 7 days and an erratic pattern tended to appear. The overall differences in patterns between the PCO and NPCO patients were confirmed by spectral statistical methods. The prevalence of certain characteristic hLHbetacf patterns may be higher among women with PCO with a more severe clinical presentation. Use of urinary analysis of gonadotropin metabolites, especially hLHbetacf, may supplement subjective ultrasound studies with more sensitive biochemical measurements.
Adult↗
Characterization of hyperactivated motility by human spermatozoa during capacitation: comparison of fertile and oligozoospermic sperm populations.
Suspensions of capacitating human spermatozoa were analyzed for potential hyperactivated movements using videomicrographic methods. Analysis was carried out on aliquots of 22 sperm suspensions, which were proved fertile several hours later during human in vitro fertilization. After approximately 3 h of capacitation, 22.1% of the fertile spermatozoa displayed motility patterns designated as hyperactivated. Over 80% of these hyperactivated spermatozoa moved with a wide-amplitude, two-dimensional whiplash pattern, displaying marked lateral displacement of the head. Only 8.4% of capacitating spermatozoa from oligozoospermic patients showed these hyperactivated movements. The incidence of hyperactivated movements by fertile and oligozoospermic spermatozoa could be significantly increased after exposure to various motility stimulants. The clinical significance of hyperactivation as a functional assay of fertilizing capacity is discussed.
Humans↗
The significance of computer-assisted semen analysis (CASA) for diagnosis in andrology and fertility prognosis.
The estimation of seminal parameters by CASA improves the objectivity, precision and reproducibility of values measured. Novel parameters, such as sperm velocity and characteristics of track direction, become measurable. An important advantage is direct on-line documentation. The biological significance of CASA parameters with respect to specific types of motility pattern or to fertility prognosis, however, is questionable. An important field is the analysis of pharmacological and toxicological influences on sperm motility. The evaluation of sperm morphology by CASA is not yet an established method.
Fertility↗
Reproduction in women reporting chronic musculoskeletal disorders.
UNLABELLED: The present population based study assessed aspects of female health as a part of a national cardiovascular screening program in 40-42 year old women in the Sor-Trondelag county. Fertility, events related to the menstrual cycle, reproduction, and the use of contraceptive methods in women reporting musculoskeletal diseases (MSD) were compared to women without these disorders (references). A higher proportion of women with MSD reported subfertility. No significant difference in mean age of menarche or menstrual cycling pattern was found, however women reporting MSD had significantly more often metrorrhagia than references. Mother's age at birth of the first and last child differed from references only in two of the patient groups, and interval between pregnancies was longer in women with MSD. Women with MSD more often chose sterilisation as a contraceptive method. CONCLUSION: Reproduction was altered in women with MSD. It remains to elucidate the interrelationship between rheumatic disorders and gynecological dysfunction.
Adult↗
[Systematic hysteroscopy prior to in vitro fertilization].
OBJECTIVE: To evaluate the benefits of a diagnostic hysteroscopy prior to in vitro fertilization. PATIENTS AND METHODS: We retrospectively studied 145 patients who underwent ICSI during a period of 6 months. Office hysteroscopy was systematically performed before the first stimulation cycle. If pathological findings were revealed, appropriate medical or surgical treatment was given. RESULTS: Pathological patterns were observed in 45% of hysteroscopies. Endometritis, polyps and myomas and mucosal diseases were the most frequently observed. The patients aged over 38 years didn't show higher rate of pathology (29% vs 27% for the younger patients). The treatment of pathologies gave the same pregnancy rate than the normal cavities. Patients with endometritis were treated with antibiotics and 40% of them became pregnant in the following cycle. DISCUSSION AND CONCLUSION: Systematic hysteroscopy prior to IVF-ICSI showed to be an effective investigation that could improve the pregnancy rate.
Adult↗
Non-Mendelian and skewed segregation of DNA markers in wide crosses of the bean rust fungus, Uromyces appendiculatus.
The inheritance of DNA markers was investigated in 27 F2 progeny from a single F1 hybrid derived from a wide cross in Uromyces appendiculatus. This cross was unusual because asexual spores were used to fertilize sexual fruiting structures. Sixty percent of the DNA markers failed to segregate according to simple Mendelian ratios. Segregation bias was evident, in that F2 progeny inherited on average 91% of maternal bands and 52% of paternal bands, which deviates significantly from the expected value for each of 75% for dominant markers. Because of these distortions, linkage mapping was not possible with this population. Evaluation of two F1s from a second wide cross, reciprocals obtained by normal fertilization, also showed non-Mendelian inheritance of one of three co-dominant RFLPs and five of six isozyme markers, indicating that the method of crossing was probably not responsible for the abnormal segregation patterns in the first cross. Either genetic incompatibility, similar to that of an interspecific cross, or selection of particular genotypes could explain the genetic anomalies reported here.
Basidiomycota↗
[Marital fertility taking into account marriage duration and age at marriage in the early 1980s in Japan].
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Asia↗
Bovine embryonic stem cells.
Bovine embryonic stem (bES) cell lines reported to date vary in morphology and marker expression, such as alkaline phosphatase (ALPL), stage-specific embryonic antigen 4 (SSEA4), and octamer-binding transcription factor-4 (OCT4), that normally are associated with the undifferentiated, pluripotent state. This chapter introduces the methods of isolating and maintaining bovine ES cells. These bovine ES cells grow in large, multicellular colonies resembling the mouse ES and embryonic germ (EG) cells, as well as human EG cells. Throughout the culture period, most of the cells within the colonies stain positive for ALPL and cell surface markers SSEA4 and OCT4. The staining patterns of the bES cells are identical to those of the blastocysts fertilized in vitro (IVF), yet different from most previously reported bovine ES cell lines, which are either negative or not detected. After undifferentiated culture for more than 1 year, these cells maintained the ability to differentiate into embryoid bodies and derivatives of all three EG layers, thus demonstrating their pluripotency. In addition to bES from IVF, this chapter introduces two methods of generating blastocyst stage embryos other than in vitro fertilization, which are parthenogenetic activation and somatic cell nuclear transfer for the potential application of generation "patient-specific" ES cells.
Animals↗
Annual and sub-annual rhythms in human conception rates: time-series analyses show annual and weekday but no monthly rhythms in daily counts for last normal menses.
Methods of time-series analysis, which are widely used to good effect in physical sciences and econometrics, have found little use in much-needed analyses of cyclical biological phenomena. Here we apply those methods to analyses of rhythmic patterns in human conception rates. Our results confirm the annual periodicity of monthly counts of total viable conceptions, demonstrate a weekday rhythm reflecting interaction of conjugal coital rhythms with individual menstrual fertility cycles, and find no evidence of any other significant repeating pattern.
Artifacts↗
Trends in embryo-transfer practice and in outcomes of the use of assisted reproductive technology in the United States.
BACKGROUND: During the past decade in the United States, increasing attention has been paid to lowering the incidence of multiple gestations resulting from the use of assisted reproductive technology. To determine whether such efforts have been successful, we assessed national trends in embryo-transfer practice patterns and in outcomes after the use of assisted reproductive technology. METHODS: We analyzed data on outcomes of assisted reproductive technology procedures as reported to the Centers for Disease Control and Prevention from 1995 to 2001 by fertility clinics in the United States. We also analyzed data from the National Center for Health Statistics on the rates of twin births and triplet or higher-order multiple births. RESULTS: From 1995 to 2001 in the United States, the number of infertility clinics, the number of fresh-embryo cycles initiated, and the number of fresh-embryo transfers increased steadily. The average number of embryos transferred per cycle began decreasing in 1997, with the steepest decline (an 11.1 percent decrease) between 1998 and 1999. In contrast, the number of pregnancies and live births per cycle during the period from 1995 to 2001 steadily increased. Even though the percentage of pregnancies with twins did not change significantly between 1997 and 2001, the percentage of pregnancies with three or more fetuses significantly decreased every year, with the steepest decline (a 20.8 percent decrease) between 1998 and 1999, after the publication in 1998 of the American Society for Reproductive Medicine guidelines for embryo transfer. CONCLUSIONS: Since 1997 in the United States, there have been consistent decreases in both the number of embryos transferred per cycle and the percentage of pregnancies with three or more fetuses, as well as a consistent increase in the percentage of live births per cycle.
Adult↗
Transcriptional gene silencing as a tool for uncovering gene function in maize.
Transcriptional gene silencing has broad applications for studying gene function in planta. In maize, a large number of genes have been identified as tassel-preferred in their expression pattern, both by traditional genetic methods and by recent high-throughput expression profiling platforms. Approaches using RNA suppression may provide a rapid alternative means to identify genes directly related to pollen development in maize. The male fertility gene Ms45 and several anther-expressed genes of unknown function were used to evaluate the efficacy of generating male-sterile plants by transcriptional gene silencing. A high frequency of male-sterile plants was obtained by constitutively expressing inverted repeats (IR) of the Ms45 promoter. These sterile plants lacked MS45 mRNA due to transcriptional inactivity of the target promoter. Moreover, fertility was restored to these promoter IR-containing plants by expressing the Ms45 coding region using heterologous promoters. Transcriptional silencing of other anther-expressed genes also significantly affected male fertility phenotypes and led to increased methylation of the target promoter DNA sequences. These studies provide evidence of disruption of gene activity in monocots by RNA interference constructs directed against either native or transformed promoter regions. This approach not only enables the correlation of monocot anther-expressed genes with functions that are important for reproduction in maize, but may also provide a tool for studying gene function and identifying regulatory components unique to transcriptional gene control.
Fertility↗
[In vivo effect of endometria's and human cervix's secretions on the spermatozoid].
OBJECTIVE: To demonstrate the capacitance stages acquired by the spermatozoa after the in vivo contact with the endometrium and the human cervical canal. STUDY TYPE: Experimental, prospective, and longitudinal. MATERIALS AND METHODS: Spermatozoa obtained from the cervix and endometrium, plus post-capacitated semen in a 1 and 4 hours process, from couples that have proved fertility, were processed to evaluate motility, morphology, vitality and identification of morphological patterns with chlortetracycline and then inducted to acrosomal reaction with ionophore A23187. RESULTS: A safe, fast and harmless technique to obtain endometrial secretions is described. The spermatozoa capacitated in vitro and in vivo developed specific capacitance stages, applying Perry's patterns with the CTC test. Spermatozoa capacitated in vitro and then recovered in the cervix responded favorably to the induction of the acrosomal reaction with calcium ionophore A23187, differing from the obtained with endometrium wash. CONCLUSIONS: The spermatozoa recovered from the endometrium presented a more advanced capacitance stage than that obtained from the cervix, this is demonstrated with the induction of the acrosomal reaction and the CTC test. These findings suggest that endometrial and cervical tissues promote capacitance, different in each one of them and progressive in their biological route.
Adult↗
Immunological testing and treatment in reproduction: frequency assessment of practice patterns at assisted reproduction clinics in the USA and Australia.
BACKGROUND: The roles that alloimmunity and autoimmunity may play in reproductive failure, including recurrent pregnancy loss and failed IVF, have not been clearly established. To help define practice patterns, we investigated what tests clinicians in the USA and Australia were offering, to which patients (diagnostic groups) the tests were recommended, and in what situations immunological/anticoagulation treatment was advised. METHODS: A five section survey was completed by senior physicians attending the annual national fertility society meetings in the USA and Australia. Results were tabulated and analysed. RESULTS: Antiphospholipid antibody testing was offered to patients with recurrent pregnancy loss by almost all physicians surveyed. Patients with previous failure of IVF were tested much less often. Other immune tests (embryotoxic assay, natural killer cells and leukocyte antibodies) were ordered by none of the Australian participants and approximately 25% of the American participants. The use of immunotherapy and anticoagulation therapy for patients who tested positive for various immunological tests was also evaluated for frequency of use and reported secondary complications. CONCLUSIONS: Large, well-structured studies examining the benefits of immunological evaluation and treatment are necessary before definite recommendations can be made.
Abortion, Habitual↗
Births averted under family planning programme: a mathematical approach.
"In this paper a probability model is proposed to describe the distribution of births to couples in first T years of marriage, when T is large and/or when couples use various methods of family planning. This model is derived on the assumption that conditional instantaneous risk of a conception, the incidence of foetal loss and the chance of attaining [sterility] following a child birth are functions of parity....The application of the model in evaluation of family planning programme changes in the child bearing pattern is illustrated."
Birth Rate↗
Paternity analysis using microsatellite markers to identify pollen donors in an olive grove.
Olive (Olea europaea L.) is a wind-pollinated, allogamous species that is generally not considered to be self-compatible. In addition, cross-incompatibilities exist between cultivars that can result in low fruit set if compatible pollinisers are not planted nearby. In this study, microsatellite markers were used to identify 17 genotypes that were potential pollen donors in a commercial olive orchard. DNA typing with the same primers was also applied to 800 olive embryos collected from five cultivars in the grove over 2 years of study. Pollen donors for the cultivars Barnea, Corregiola, Kalamata, Koroneiki, and Mission were estimated by paternity analysis, based on the parental contribution of alleles in the genotypes of the embryos. The exclusion probability for the marker set was 0.998 and paternity was assigned on the basis of the 'most likely method'. Different pollen donors were identified for each of the maternal cultivars indicating that cross-compatibilities and incompatibilities varied between the genotypes studied. Cross-pollination was the principal method of fertilization, as selfing was only observed in two of the embryos studied and both of these were from the cultivar Mission. This is the first report where these techniques have been applied to survey the pollination patterns in an olive grove. The results indicate that careful planning in orchard design is required for efficient pollination between olive cultivars.
Agriculture↗