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PubMed2002

Insurance coverage and outcomes of in vitro fertilization.

BACKGROUND: Although most insurance companies in the United States do not cover in vitro fertilization, a few states mandate such coverage. METHODS: We used 1998 data reported to the Centers for Disease Control and Prevention by 360 fertility clinics in the United States and 2000 U.S. Census data to determine utilization and outcomes of in vitro fertilization services according to the status of insurance coverage. RESULTS: Of the states in which in vitro fertilization services were available, 3 states (31 clinics) required complete insurance coverage, 5 states (27 clinics) required partial coverage, and 37 states plus Puerto Rico and the District of Columbia (302 clinics) required no coverage. Clinics in states that required complete coverage performed more in vitro fertilization cycles than clinics in states that required partial or no coverage (3.35 vs. 1.46 and 1.21 transfers per 1000 women of reproductive age, respectively; P<0.001) and more transfers of frozen embryos (0.43 vs. 0.30 and 0.20 per 1000 women of reproductive age, respectively; P<0.001). The percentage of cycles that resulted in live births was higher in states that did not require any coverage than in states that required partial or complete coverage (25.7 percent vs. 22.2 percent and 22.7 percent, respectively; P<0.001), but the percentage of pregnancies with three or more fetuses was also higher (11.2 percent vs. 8.9 percent and 9.7 percent, respectively; P=0.007). The number of fresh embryos transferred per cycle was lower in states that required complete coverage than in states that required partial or no coverage (P=0.001 and P<0.001, respectively). CONCLUSIONS: State-mandated insurance coverage for in vitro fertilization services is associated with increased utilization of these services but with decreases in the number of embryos transferred per cycle, the percentage of cycles resulting in pregnancy, and the percentage of pregnancies with three or more fetuses.

Ambulatory Care Facilities↗
PubMed2001

The initial fertility consultation: recommendations concerning cigarette smoking, body mass index, and alcohol and caffeine consumption.

Obstetrician-gynecologists are frequently consulted by couples who are concerned about their fertility potential. During the initial fertility consultation, questions may arise concerning the potential impact of lifestyle choices on fertility. For the female partner, common exposures associated with a decrease in fertility are cigarette smoking, alcohol consumption of >4 drinks per week, and caffeine intake of >250 mg daily. For the female partner, a body mass index of >27 kg/m2 or <17 kg/m2 is associated with decreased fertility. On the basis of the evidence from epidemiologic studies, couples who are concerned about their fertility potential should stop the use of tobacco products. In addition, the female partner should limit alcohol consumption to no more than 4 drinks per week, decrease caffeine intake to no more than 250 mg daily, and adjust calorie intake and exercise levels to achieve a body mass index between 20 and 27 kg/m2.

Alcohol Drinking↗
PubMed2003

Pregnancy outcome in spontaneous twins versus twins who were conceived through in vitro fertilization.

OBJECTIVE: The purpose of this study was to compare maternal and neonatal complications in spontaneous versus in vitro fertilization twins. STUDY DESIGN: Twin gestations that were delivered from 1995 to 2000 were reviewed. Cases consisted of 56 in vitro fertilization twins, each of which was matched to two control mothers by age and parity. They were compared regarding various maternal and neonatal complications. RESULTS: In vitro fertilization twins were more likely to have preterm labor compared with control twins, with no difference in the incidences of pregnancy-induced hypertension, gestational diabetes mellitus, placenta previa, or preterm premature rupture of membranes between the two groups. The cesarean delivery rate was significantly higher in cases of twins who were conceived by in vitro fertilization (76.8% vs 58.0%, P=.026), despite a similar rate of elective cesarean delivery and the incidence of nonvertex twin A in both groups. The preterm delivery rate was significantly higher (67.9% vs 41.1%, P=.002) and the gestational age was significantly lower (35+/-3 weeks vs 36+/-3 weeks, P=.043) in cases compared with control subjects. Both twins were, on the average, 230 g lighter in the in vitro fertilization group compared with the control group. However, intrauterine growth restriction was more frequent in the control group (36.6% vs 25%, P=.044). There was a significantly higher incidence of admission to the neonatal intensive care unit, respiratory distress syndrome, a need for mechanical ventilation, and pneumothorax in cases compared with control subjects. CONCLUSION: When compared with spontaneous twins, in vitro fertilization twins are more likely to be delivered by cesarean delivery and to have a higher incidence of preterm birth and prematurity-related respiratory complications with a longer nursery stay.

Adult↗
PubMed1994

Effect of active immunization against the amino-terminal peptide (alpha N) of the alpha 43 kDa subunit of inhibin (alpha 43) on fertility of ewes.

Immunization against the amino-terminal peptide (alpha N) of the alpha 43 subunit of inhibin was shown previously to reduce fertility in ewes. The aim of this study was to examine the effects of active immunization of ewes against alpha N on egg recovery and fertilization rates. Ewes were immunized against alpha N immunogen, and were given 800 I.U. of pregnant mare's serum gonadotrophin at the end of treatment with intravaginal progesterone to synchronize the oestrous cycles. Control ewes received adjuvant only. The ewes were run with fertile rams, and 4 days after withdrawal of the progesterone device the oviducts were flushed to recover eggs and luteal structures on the ovaries were recorded. Eggs were recovered from 17/19 (90%) control ewes compared with 4/16 treated ewes (25%) (P < 0.01), and the egg recovery rates were 76% (45/59) and 17% (7/42) respectively (P < 0.001). The mean number of corpora lutea (CL) per ewe were similar (3.1 +/- 1.4 v. 2.6 +/- 1.0) but several CL in the treated ewes did not appear to have ruptured, and 2 treated ewes had cystic follicles and no CL. There were no apparent differences in either the fertilization rates or the stages of development of fertilized eggs between treated and control ewes. Antibody binding levels in follicular fluid were approximately half those found in peripheral plasma. It is concluded that immunization of ewes against alpha N leads to lowered fertility by suppressing ovulation, implicating alpha N in the normal ovulatory process.

Animals↗
PubMed1999

Requirement of a Src family kinase for initiating calcium release at fertilization in starfish eggs.

Signal transduction leading to calcium release in echinoderm eggs at fertilization requires phospholipase Cgamma-mediated production of inositol trisphosphate (IP(3)), indicating that a tyrosine kinase is a likely upstream regulator. Because previous work has shown a fertilization-dependent association between the Src homology 2 (SH2) domains of phospholipase Cgamma and a Src family kinase, we examined whether a Src family kinase was required for Ca(2+) release at fertilization. To inhibit the function of kinases in this family, we injected starfish eggs with the SH2 domains of Src and Fyn kinases. This inhibited Ca(2+) release in response to fertilization but not in response to injection of IP(3). We further established the specificity of the inhibition by showing that the SH2 domains of several other tyrosine kinases (Abl, Syk, and ZAP-70), and the SH3 domain of Src, were not inhibitory. Also, a point-mutated Src SH2 domain, which has reduced affinity for phosphotyrosine, was a correspondingly less effective inhibitor of fertilization-induced Ca(2+) release. These results indicate that a Src family kinase, by way of its SH2 domain, links sperm-egg interaction to IP(3)-mediated Ca(2+) release at fertilization in starfish eggs.

Animals↗
PubMed2000

Rearrangements of sea urchin egg cytoplasmic membrane domains at fertilization.

Fertilization in the sea urchin is accompanied by rapid reorganization of the egg endoplasmic reticulum (ER). ER-derived vesicles contribute to one of three classes of membranes used in assembling the male pronuclear envelope in vitro. We provide here biochemical evidence for the rearrangement of sea urchin egg cytoplasmic membrane domains at fertilization up to the first mitosis, with respect to two nuclear envelope markers, lamin B and lamin B receptor (LBR), using purified vesicles prepared from homogenates fractionated by floatation on sucrose gradients. In unfertilized eggs, immunoprecipitation data indicate that most of lamin B and LBR are localized in the same vesicles but do not interact. By 3 min post-fertilization, both proteins are more widely distributed across the gradients and by 12 min most of lamin B and LBR are localized in vesicles of different densities. This partitioning is maintained throughout S phase. At mitosis, most lamin B and LBR remain in distinct vesicles, while a small proportion of lamin B and LBR, likely derived from the disassembled nuclear envelope, associate in a minor subset of vesicles. The results illustrate a dynamic reorganization of egg cytoplasmic membranes at fertilization, and the establishment of distinct membrane domains enriched in specific nuclear envelope markers during the first cell cycle of sea urchin development. Additionally, we demonstrate that male pro-nuclear membrane assembly occurs only when both cytosol and membranes originate from fertilized but not unfertilized eggs, suggesting that fertilization-induced membrane rearrangements contribute to the ability of the egg to assemble the male pronuclear envelope.

Animals↗
PubMed1976

Fertilizer calcium as a factor affecting the voluntary intake, digestibility and retention time of pangola grass (Digitaria decumbens) by sheep.

1. Pangola grass (Digitaria decumbens) grown with and without calcium fertilizer was cut at three stages of regrowth to measure voluntary intake of dry matter (DM) and digestibility of various components of the dried-grass diet by sheep kept in metabolism crates. To determine the extent of a simple Ca deficiency half the sheep on each diet was supplemented with 1-4 g Ca/d. Retention times of the various dietary components in the reticulo-rumen were also determined. 2. Feeding a Ca supplement had no effect on voluntary intake or digestibility. 3. Ca fertilizer increased the Ca content of the grass from 2-2 to 3-8 g/kg DM and DM digestibility from 0-455 to 0-476 (P less than 0-01) due to an increase in the digestibility of the hemicellulose. 4. Voluntary intake was increased from 38-8 to 43-2 g/kg body-weight0.75 per d by Ca fertilizer due to an 18% reduction in the period of time the DM was retained in the reticulorumen. 5. Regressions relating voluntary intake to DM digestibility for the Ca-fertilized and control grass were significantly different (P less than 0-01). When compared at the same DM digestibility the voluntary intake of the Ca-fertilized grass was 2-6 g/kg body-weight0.75 per d higher than that of the control. 6. It was concluded that Ca fertilizer increased both DM digestibility and voluntary intake as a result of changes in the structural composition of the grass and not by a simple increase in the Ca content of the diet.

Animal Feed↗
PubMed2002

Influence of mating sex ratio in commercial pheasant flocks on bird health and the production, fertility, and hatchability of eggs.

1. The effects of two mating ratios (8:1 and 12:1 females:males) on bird health, egg production and quality, fertility (employing macroscopic and microscopic techniques) and hatchability were examined for pheasants (Phasianus colchinus) on a commercial game farm, to provide a baseline data set for production of pheasants under specific conditions. 2. Mating ratio did not significantly affect mortality or pathology of breeding birds. 3. Egg production was significantly higher for the 8:1 mating ratio over the first 5 weeks of the trial but this difference disappeared during the second half of the trial. 4. Incidence of rejected eggs increased as the season progressed, mainly due to poor shell quality, but it was not significantly affected by mating ratio. 5. Fertility of eggs produced from birds under an 8:1 mating ratio was consistently and significantly 4% higher than fertility of eggs from the 12:1 mating ratio. The incidence of eggs showing no sign of mating (no sperm) was twice as high for the 12:1 pens (13.7% of the sample). There was good agreement between macroscopic and microscopic examination of fertility in eggs. Higher fertility in the 8:1 pens appeared to be related to a higher proportion of the females being recruited and mated. 6. Hatchability was significantly improved by adopting an 8:1 mating ratio, presumably due to the higher fertility of the eggs. Candling of the eggs improved hatchability but only for the 12:1 pens probably because more clear eggs were removed from the tray.

Animals↗
PubMed2005

Can testosterone and corticosterone predict the rate of display of male sexual behaviour, development of secondary sexual characters and fertility potential in primary broiler breeders?

1. Genetic selection for growth to enhance production may be associated with stress and with modified physiological and behavioural phenotypes which depress male primary broiler breeder fertility. 2. We hypothesised that male serum testosterone (T) and corticosterone (C) concentrations might correlate with fertility, sexual behaviour, and testicular, comb and wattle size. 3. Cockerels from two genetic strains (A and B) of primary broiler breeder were penned individually with an average of 10 females across 5 age periods (30 to 51 weeks) to evaluate male fertility, behaviour, serum T and C, and comb, wattle and testicular dimensions. 4. Strain A males had higher T at age periods 2, 4 and 5 than Strain B. Both strains had basal concentrations of C, apart from an elevated concentration for Strain B in period 5. 5. Strain B had a weak but significant, positive correlation between sexual behaviour and T and C, while Strain A males with higher C had larger combs and wattles. 6. Neither T nor C correlated with fertility. We conclude that evaluation of these endocrine factors (quantifiable measurements with the potential to correlate with fertility) alone seems insufficient to predict male fertility potential in these strains of primary broiler breeder.

Aging↗
PubMed2001

Population pressure and fertility in pre-transition Thailand.

Before the demographic transition in Thailand, fertility was high, but not uniformly so. As in other pre-transition settings, Thai fertility responded to pressures and opportunities created by socioeconomic structure and land availability. Drawing upon provincial data from the 1947 and 1960 censuses of Thailand, we find a strong 'frontier effect' on Thai fertility in the 1950s. Fertility was higher in sparsely settled frontier provinces and lower in provinces with higher population density relative to cultivatable land. This finding is robust and holds up with controls for agricultural employment, land quality, and the sex ratio (an indicator of sex-selective migration). The effect of population pressure lowers the likelihood of marriage and of marital fertility. The findings from Thailand are consistent with the research of Easterlin on the nineteenth century United States and with other pre-transition societies. We suggest how demographic transition theory might be broadened to include fertility dynamics in pre-transition societies.

Fertility↗
PubMed2002

Distinctive features of age-specific fertility profiles in the English-speaking world: common patterns in Australia, Canada, New Zealand and the United States, 1970-98.

The paper seeks to identify common features in the fertility patterns of the English-speaking world and provide a model basis for comparison of fertility between countries and over time. Attention is focused on the heterogeneity within the fertility patterns of Australia, Canada, New Zealand, and the United States, similar to that reported earlier for the UK and the Irish Republic. The recent age-specific fertility patterns of these countries display a marked 'bulge' in fertility of women under age 25. A mixture model with two-component Hadwiger functions provides a suitable fit. The heterogeneity thus suggested is related to the proportion of births outside marriage. Additionally, there is some evidence that, in the United States, and lesser extent in New Zealand, this heterogeneity in fertility patterns may be explained by ethnic difference in the timing and number of births.

Australia↗
PubMed1995

Marital fertility control among the Qing nobility: implications for two types of preventive check.

Demographers, as early as Malthus, have assumed that the preventive checks, delayed marriage and celibacy, were absent in traditional China. In this paper on the Qing (1644-1911) imperial lineage, we demonstrate that, instead, there may have been a different, more 'modern' preventive check: fertility control within marriage. Marital fertility of lineage couples during the eighteenth and nineteenth centuries was low to moderate. Such low fertility was the product of three behavioural mechanisms: late starting, early stopping and, most significantly, long spacing. Couples apparently regulated their fertility according to their economic resources and the sex of their surviving children. Moreover, they did so, we suggest, by regulating their coital frequency. Deliberate fertility control, in other words, was already within the 'calculus of conscious choice' for some Chinese well before this century. the speed of contemporary sinitic fertility transitions may accordingly be attributed to the fact that they did not require a change in attitudes, only the diffusion of new incentives and effective technologies.

Birth Intervals↗
PubMed2005

Men's influence on the onset and progress of fertility decline in Ghana, 1988-98.

While lower fertility is commonly associated with women's reproductive autonomy, we demonstrate that the influence of men's education on reproductive decision-making increased during the first decade of rapid fertility decline in Ghana. Husband's education exerts a stronger influence on wife's fertility intentions than does her own education, and the magnitude of the effect of his education increased significantly from 1988 to 1998. Lower fertility in Ghana seems to be associated more with men's declining fertility desires than with women's increasing reproductive autonomy. Nevertheless, there is some indication that women's education may play a relatively greater role in reproductive decision-making as fertility decline progresses still further.

Adult↗
PubMed2006

Religious differentials in marital fertility in The Hague (Netherlands) 1860-1909.

Previous studies of the marital fertility transition in Europe have found religious differentials. Using data collected from the population registers of The Hague, our aim in this study is to search for answers to the following questions: whether religious differentials result from socio-economic characteristics; to what extent religious ideology explains the behaviour of religious groups; which proximate determinants account for the religious differentials; and whether the Jews were forerunners in the marital fertility transition in Europe. The results provide some evidence of relatively low levels of parity-dependent fertility control among Jews before the transition and among Catholics during the transition. Religious ideology probably accounts for the low level of fertility control among Catholics. The ultimate reason for the relatively high marital fertility among Jews before the transition remains unclear. Our findings do not support the hypothesis that Jews were forerunners in the marital fertility transition.

Adult↗
PubMed2006

Marital fertility and religion in Spain, 1985 and 1999.

Since the transition to democracy in Spain in 1975, both total fertility and rates of church attendance of Catholics have dropped dramatically. In this study the 1985 and 1999 Spanish Fertility Surveys were used to investigate whether the significance of religion for fertility behaviour -- current family size and the spacing of births -- changed between the survey dates. In the 1985 survey, family size was similar for those Catholics who actively participated in religious activities and those who, though nominally Catholic, were not active participants. By 1999, the family size of the latter was lower and comparable to the family size of those without religious affiliation. These findings accord with the declines in both church attendance and fertility in Spain. The small groups of Protestants and Muslims had the highest fertility. Women in inter-faith unions had relatively low fertility.

Adolescent↗
PubMedDate not supplied

Acrosome reaction in fertile and subfertile boar sperm.

The main purpose of sperm evaluation is to predict its fertilizing ability. However, basic sperm test results show a low correlation with fertilizing ability. The purpose of this study was to determine whether there is an association between acrosome reaction (AR) and the incidence of subfertility of normal sperm boar. The production records of 22 farms were analyzed to identify boars with low fertility and/or prolificity, classified as subfertile. Twenty-two subfertile boar semen samples were analyzed and compared with 51 samples of fertile boars. Sperm were capacitated during 4 h at 39 degrees C. viability was determined by bisbenzimide (Hoechst-33258) staining. Acrosome reaction was assessed with fluorescein isothiocyanate conjugated Pisum sativum agglutinin. The percentage of spontaneous acrosome reaction (SAR) was not significantly different in fertile (4.5%) and subfertile boars (4.75%) (p > .05). Nevertheless, the percentage of progesterone-induced acrosome reaction (IAR) was significantly lower in subfertile boars (5.75%) as compared with fertile boars (10%) (p < .01). These results suggest that assessment of IAR in vitro may be a useful parameter to identify subfertility in boars.

Acrosome Reaction↗
PubMedDate not supplied

Expression of lectin receptors on the membrane surface of sperm of fertile and subfertile boars by flow cytometry.

Studies suggest that carbohydrates are important in different stages of fertilization. Plasma membrane changes accompanying in vitro capacitation and acrosome reaction (AR), such as removal or appearance of specific glycoproteins, have been studied using lectins that bind specifically to carbohydrate residues. In specialized artificial insemination farms and semen production centers, identification of boars with decreased fertilization ability (subfertility) is a newborn necessity. This investigation is a sequential study to determine the kinetics of surface carbohydrates turnover during in vitro capacitation and AR in fertile and subfertile boar sperm. Flow cytometry determinations of the binding of three FITC-labeled lectins were assessed. WGA binding was significantly lower in fresh, capacitated, and acrosome-reacted sperm of subfertile boars than in fertile boars. Con-A binding was not significantly different in fresh sperm of fertile and subfertile boars. However. Con-A labeling in capacitated, and acrosome-reacted sperm differed significantly in both groups. UEA binding increased only in capacitated sperm of subfertile boars. These findings could be used as indicators of capacitation and AR and may also be a good indicator of sperm fertilizing ability in boars.

Acrosome Reaction↗
PubMedDate not supplied

Sperm surface protein profiles of fertile and infertile men: search for a diagnostic molecular marker.

The present study was conducted to examine whether there is any difference in the protein profiles of sperm membranes of fertile (n = 37) and infertile (n = 29) men. In the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) procedure, the sperm extracts of fertile and infertile men showed 12-16 major and 8-14 minor common protein bands in various molecular regions. However, there was an additional band of approximately 78 kD present in the sperm extracts of approximately 80% of infertile men that was absent in the sperm extracts of fertile men. In the remaining approximately 20% of the infertile men, it was of relatively weaker intensity. This band was present only in the sperm extracts and not in the seminal plasma, whether of fertile or infertile men, and was designated as the infertility-associated sperm protein (IASP). Antibodies to IASP specifically immunoprecipitated the approximately 78-kD protein from the sperm extracts of only infertile and not the fertile men. In the immunofluorescence technique, the anti-IASP antibodies reacted strongly with the head and/or midpiece regions of morphologically abnormal sperm and cross-reacted with a protein in the equatorial regions of morphologically normal sperm of fertile men. The IASP molecule and its antibodies may provide molecular tools to differentiate between the normal and abnormal sperm, and, thus, may be useful markers for the diagnosis of male-factor infertility.

Biomarkers↗