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PubMed1994

High fecundity rates following in-vitro fertilization and embryo transfer in antiphospholipid antibody seropositive women treated with heparin and aspirin.

This study was undertaken to explore whether intervention with heparin and aspirin (H/A) in selected patients undergoing in-vitro fertilization (IVF) and embryo transfer could improve fecundity rates. Specifically, it explored the possibility that women diagnosed with organic pelvic disease who demonstrated antiphospholipid antibodies (APA) could benefit from H/A administration in a similar manner to that used in patients with recurrent pregnancy loss. We used an enzyme-linked immunosorbent assay for six different phospholipids to identify patients who expressed APA before they underwent IVF/embryo transfer. This study was confined to the first IVF/embryo transfer cycle that followed assessment of APA status and accordingly, the number of IVF/embryo transfer cycles corresponds with the number of patients treated. APA seropositive patients were treated with aspirin, 81 mg orally q.d., and heparin 5000 IU s.c. b.i.d., beginning on day 1 of controlled ovarian stimulation. The endpoint for success was a live birth or an ultrasound confirming fetal cardiac activity (a viable pregnancy). The prevalence of APA in patients diagnosed with organic pelvic disease (53%) was much higher than in those without female pathology (14%). The administration of H/A to APA seropositive patients significantly (P < 0.05) improved the viable pregnancy rate (49%) compared to the untreated APA seropositive group (16%). The viable pregnancy rate for APA seropositive women treated with H/A was also significantly (P < 0.001) higher than for untreated APA seronegative patients (27%). We conclude that all women undergoing IVF/embryo transfer should be tested for APA prior to initiating ovarian stimulation and those with APA seropositivity should be treated with H/A.

Adult↗
PubMed1994

Association of dopamine D2 receptor gene haplotypes with anovulation and fecundity in female Hispanics.

Dopamine is an important neurotransmitter in the hypothalamic control of gonadotrophin secretion. Neuron response is mediated through one of five different dopamine receptors. We explored the association of D2 receptor gene polymorphisms with disorders of ovulation. We utilized a multiplex allele specific polymerase chain reaction (PCR) to detect two bi-allelic polymorphisms (four potential haplotypes) in intron 5 and exon 6 of the D2 receptor gene. A second PCR/restriction endonuclease digest was utilized to verify this. Using these assays, 185 female Hispanics (51% with known ovulatory dysfunction and 49% with normal function) were haplotyped. One allele (3) was not present in the population and there were no significant differences in remaining allele distribution between ovulatory and anovulatory patients. However, significant associations were noted between alleles and gonadotrophins and fecundity. The 4 allele had a different reproductive profile compared to the 2 allele. The 4 allele was associated with significantly higher concentrations of luteinizing hormone (LH) (means +/- SE) (19.2 +/- 2.2 versus 12.3 +/- 1.3 mIU/ml, P < 0.02) and follicle stimulating hormone (FSH) (13.2 +/- 2.0 versus 10.0 +/- 0.6 mIU/ml, P < 0.05), significantly lower concentrations of prolactin (7.9 +/- 0.8 versus 14.9 +/- 3.5 ng/ml, P < 0.02) and higher parity (1.4 +/- 0.12 versus 0.92 +/- 0.13) and lower miscarriage rates (0.89 +/- 0.1 versus 1.33 +/- 0.24, P < 0.04). We conclude that D2 receptor alleles may be associated with reproductive success through altered gonadotrophin secretion and that this effect may be independent of ovulatory function.

Adult↗
PubMed2005

The effects of methotrexate on Drosophila development, female fecundity, and gene expression.

Methotrexate (MTX), a synthetic folate analog, is a tight-binding inhibitor of dihydrofolate reductase (DHFR), a key enzyme for the biosynthesis of purines, thymidylate, and several amino acids. As a consequence, MTX decreases titres of reduced folates, interferes with DNA synthesis, and results in the arrest of rapidly proliferating cells, making it a drug of choice for the treatment of a variety of cancers and auto-immune disorders. MTX is also a known teratogen in all higher animals tested, but there is little information about the effects of this drug on invertebrates. Here we show that MTX has little effect on the survival of Drosophila melanogaster adult flies, but severely diminishes female fecundity. Reduced oviposition, coupled with aberrant egg morphologies, resulted in near sterility of MTX-treated females. Rare surviving progeny showed developmental abnormalities including larval tumors, and bristle, wing, eye, and leg defects. To determine if these phenotypes could be attributed solely to DHFR inhibition, microarray analysis was undertaken and included MTX-treated females, ovaries, and cell line samples. Genes encoding transcripts that were perturbed by the drug were verified using quantitative real-time RT-PCR. Many of these genes were involved in cell cycle regulation, signal transduction, transport, defense response, transcription, or various aspects of metabolism. These studies show that MTX treatment has multiple targets and, in addition, provides a new invertebrate model for the study of teratogenesis.

Animals↗
PubMed1995

Reproductive senescence in female Japanese monkeys (Macaca fuscata): age- and season-related changes in hypothalamic-pituitary-ovarian functions and fecundity rates.

Age- and season-related changes in gonadotropin-gonadal functions were studied in captive female Japanese monkeys (Macaca fuscata fuscata), with special reference to reproductive senescence. In experiment 1, a total of 57 nonlactating females at ages 3-32 yr were used. Blood samples were collected for at least one breeding season (September through March), and changes in plasma concentrations of LH, estradiol, and progesterone were examined. In experiment 2, two groups of females (older females, n = 5, over 21 yr old; mature females, n = 5, aged 8-12 yr) received s.c. injections of 50 micrograms/kg of estradiol benzoate during the mid-breeding season. In experiment 1, ovarian functions as well as fecundity rates were maintained in the animals aged 5-20 yr. A decline in ovarian activity became apparent at 21-25 yr of age, when animals exhibited a slight increase in plasma LH during the breeding season. Onset of menopause occurred at around 27 yr of age, near the end of the life span. Menopausal females exhibited a marked seasonal difference in plasma LH concentrations, with high levels during the breeding season. In experiment 2, estradiol treatment elicited an LH surge in both old and mature females. The marked seasonal difference in plasma LH, as well as the maintenance of LH response to estradiol in menopausal females, suggests a possibility that biannual changes in sensitivity of the hypothalamo-hypophysial axis to the negative feedback action of estradiol are maintained even after menopause.

Aging↗
PubMed1996

Effects of passive immunization against inhibin-peptide on secretion of follicle-stimulating hormone and ovulation rate in ewes carrying the Booroola fecundity gene.

Objectives of the study were to determine whether 1) inhibin negative feedback regulation of FSH secretion is diminished in ewes carrying a copy of the Booroola fecundity (FecB) gene and 2) differential FSH secretion is obligatory for expression of gene-specific differences in ovulation rate (OR). The approach was to compare FSH and ovulatory responses to passive immunoneutralization of inhibin in ewes with and without a copy of the FecB gene. Twenty-eight 2- to 3-yr-old ewes were assigned within genotype to antibody (alpha-IF-Ab) or control groups. Genotypes consisted of 3/4 Rambouillet x 1/4 Booroola ewes with one copy of the FecB gene (FecB+; 57 kg) and 3/4 Rambouillet x 1/4 Booroola ewes without the FecB gene (++; 59 kg). Estrus was synchronized during the breeding season using progesterone-releasing pessaries (CIDR-G). Pessaries were removed at 0 h. A single injection of alpha-IF-Ab or control solution was given at -48 h. Alpha-IF-Ab had been developed against a synthetic inhibin fragment matching the N-terminal region of ovine inhibin's alpha subunit. For injection, alpha-IF-Ab had been precipitated from ovine immune sera and concentrated. Blood samples were collected at 6-h intervals from -48 to 48 h, and laparoscopy was performed 14 days after CIDR-G withdrawal. All ewes exhibited estrus and ovulated. Genotype and alpha-IF-Ab treatment were without effect on intervals to estrus. Both factors affected OR (p < or = 0.001). Mean OR in control ++ and FecB+ ewes were 1.6 and 2.7, respectively; mean OR in alpha-IF-Ab-treated ++ and FecB+ ewes were 2.5 and 4.6, respectively. Following injection of alpha-IF-Ab, FSH concentrations increased within 6 h, peaked 12-18 h later, and then declined. Magnitude of FSH increases was similar in ++ and FecB+ ewes (70% and 85% over control values, respectively). Results demonstrate that 1) inhibin negative feedback regulation of FSH secretion is not a site of FecB gene action and 2) the mechanism by which the FecB gene increases OR does not necessarily involve increased FSH secretion during the period of preovulatory follicular development.

Animals↗
PubMed1997

Reduced fecundity in insulin-like growth factor-binding protein-1 transgenic mice.

Transgenic mice that overexpress insulin-like growth factor-binding protein-1 (IGFBP-1) demonstrate a reduced litter size compared to nontransgenic, wild-type mice derived from the same genetic background. To determine the mechanism underlying this phenomenon, we examined the number of ovulatory follicles per cycle in naturally mated transgenic and wild-type mice by counting the corpora lutea and the blastocysts harvested by uterine flushing. In addition, we investigated the effects of insulin-like growth factor-I (IGF-I) on blastocyst DNA synthesis and examined the effects of a transgenic maternal environment on fetal outcome by cross transfer of blastocysts. Significantly fewer corpora lutea were observed in ovaries from transgenic vs. wild-type mice (7.6 +/- 1.8 vs. 11.8 +/- 1.5), and fewer blastocysts were harvested from transgenic mice compared to wild-type mice (7.6 +/- 2.3 vs. 10.1 +/- 2.0). DNA content and basal DNA synthesis were similar in blastocysts from nontransgenic and transgenic mice. However, unlike wild-type blastocysts, transgenic blastocysts did not respond to IGF-I with an increase in DNA synthesis. To determine the effects of maternal environment on fetal outcome, a mixture of equal numbers of transgenic and nontransgenic blastocysts was transferred into foster mothers. The ratio of transgenic to nontransgenic pups was not significantly different from the theoretically predicted value of 1. However, the litter size was significantly reduced in wild-type compared to transgenic foster mothers. These data suggest that the reduced fecundity is due to reduced ovulation and blastocyst number. Furthermore, expression of the transgene in neither the blastocyst nor the maternal tissues had any significant negative effect on implantation or fetal wastage.

Animals↗
PubMed2000

Retrospectively sampled time-to-pregnancy data may make age-decreasing fecundity look increasing. European Infertility and Subfecundity Study Group.

The retrospective study based on pregnancy samples is the most commonly used method for studying time to pregnancy. Using a simple Monte Carlo simulation, this note focuses on a particular selection bias problem associated with this design: even if each woman's fecundity decreases with age, estimation of the effect of age may show the opposite trend. We recommend exercising increased caution in interpreting findings from pregnancy-based time-to-pregnancy studies.

Adult↗
PubMed2002

Midluteal endometrial biopsy and alphavbeta3 integrin expression in the evaluation of the endometrium in infertility: implications for fecundity.

It has been recently proposed that the immunohistochemical evaluation of alphavbeta3 integrin in combination with histologic dating in midluteal endometrial biopsy specimens should be performed to evaluate the endometrial receptivity in the infertile patient. However, no studies have attempted to correlate these findings with subsequent fecundity. In 100 consecutive infertile patients (mean age 31.9+/-3.4 years) undergoing a routine work-up, two endometrial biopsies were performed during a single menstrual cycle: a midluteal biopsy on postovulatory days 6 to 8 and another biopsy 4 days later. Histological dating and immunohistochemical evaluation of alphavbeta3 integrin expression were done in all endometrial biopsy specimens. All patients were followed without treatment during 18 to 24 months (mean 23.5+/-1.4, range 18 to 24). Twenty-five midluteal biopsies showed out-of-phase endometria, whereas all but one late-luteal biopsy specimens were in-phase. Glandular alphavbeta3 integrin expression was observed in 50% of midluteal specimens with this expression being significantly more frequent among in-phase (63%) than among out-of-phase (12%) specimens (p<0.001). However, all late-luteal specimens strongly expressed this integrin. Thirty-eight women became spontaneously pregnant during the follow-up period, 32 ended in a live birth and 6 in first trimester spontaneous abortion. The Cox regression method showed no differences between the hazard of pregnancy when the alphavbeta3 integrin-positive and -negative groups were compared (odds ratio 1.25; 95% confidence interval [CI] 0.66-2.36; p=0.49) or when patients with in-phase endometria were compared with those with delayed endometrial maturation (odds ratio 1.12; 95% CI 0.53-2.37; p=0.76). In conclusion, neither midluteal histological evaluation nor alphavbeta3 integrin expression in mid- or late-luteal endometrial biopsy specimens correlated with outcome for subsequently untreated infertile women.

Abortion, Spontaneous↗
PubMed1999

The effect of smelter work on fecundity.

Time to pregnancy (TTP) has been proposed as a screening instrument for the detection of environmental and occupational hazards to reproduction. Our aim was to determine whether reduced fecundity could be found among smelter workers and couples living near the smelter. The number of Months required to achieve a pregnancy was determined via a questionnaire, and TTP was analyzed using a logistic regression model with a cutoff at 12 months. No significant findings were found for a risk of having to wait for more than 12 months to achieve pregnancy because of occupational or environmental exposure. It could be that the exposure variables tested were not sensitive enough in detecting hazards to reproduction or that they were of minor importance. A tendency toward a prolonged TTP was found for couple living near the smelter.

Adult↗
PubMed1997

The effect of cowpox virus infection on fecundity in bank voles and wood mice.

Although epidemic infectious diseases are a recognized cause of changes in host population dynamics, there is little direct evidence for the effect of endemic infections on populations. Cowpox virus is an orthopoxvirus which is endemic in bank voles (Clethrionomys glareolus), wood mice (Apodemus sylvaticus) and field voles (Microtus agrestis) in Great Britain. It does not cause obvious signs of disease nor does it affect survival, but in this study we demonstrate experimentally that it can reduce the fecundity of bank voles and wood mice by increasing the time to first litter by 20-30 days. The pathogenic mechanisms causing this effect are at present not known, but this finding suggests that natural subclinical infection could have a considerable effect on the dynamics of wild populations.

Animals↗
PubMed2000

The relative roles of density and climatic variation on population dynamics and fecundity rates in three contrasting ungulate species.

The relative influences of density-dependent and -independent processes on vital rates and population dynamics have been debated in ecology for over half a century, yet it is only recently that both processes have been shown to operate within the same population. However, generalizations on the role of each process across species are rare. Using a process-orientated generalized linear modelling approach we show that variations in fecundity rates in populations of three species of ungulates with contrasting life histories are associated with density and winter weather in a remarkably similar manner. However, there are differences and we speculate that they are a result of differences in size between the species. Much previous research exploring the association between vital rates, population dynamics and density-dependent and -independent processes has used pattern-orientated approaches to decompose time-series into contributions from density-dependent and -independent processes. Results from these analyses are sometimes used to infer associations between vital rates, density and climatic variables. We compare results from pattern-orientated analyses of time-series with process-orientated analyses and report that the two approaches give different results. The approach of analysing relationships between vital rates, density and climatic variables may detect important processes influencing population dynamics that time-series methodologies may overlook.

Animals↗
PubMed2004

Evidence for maternally inherited factors favouring male homosexuality and promoting female fecundity.

The Darwinian paradox of male homosexuality in humans is examined, i.e. if male homosexuality has a genetic component and homosexuals reproduce less than heterosexuals, then why is this trait maintained in the population? In a sample of 98 homosexual and 100 heterosexual men and their relatives (a total of over 4600 individuals), we found that female maternal relatives of homosexuals have higher fecundity than female maternal relatives of heterosexuals and that this difference is not found in female paternal relatives. The study confirms previous reports, in particular that homosexuals have more maternal than paternal male homosexual relatives, that homosexual males are more often later-born than first-born and that they have more older brothers than older sisters. We discuss the findings and their implications for current research on male homosexuality.

Birth Order↗
PubMed2004

Fecundity and MHC affects ejaculation tactics and paternity bias in sand lizards.

We demonstrate that extending copulation enhances probability of paternity in sand lizards and that determinants of copulation duration depend on a males' mating order (first or second). First males, with no information on presence of rivals, extend copulation when mating with a more fecund female. Second males, however, adjust copula duration in relation to a first male's relatedness with his female, which there is reason to believe can be deduced from the MHC-related odor of the copulatory plug. Male-female relatedness negatively influences a male's probability of paternity, and when second males are in a favored role (i.e., the first male is the one more closely related to the female), second males transfer larger ejaculates, resulting in higher probability of paternity. This result corroborates predictions from recent theoretical models on sperm expenditure theory incorporating cryptic female choice and sexual conflict. More specifically, the results conform to a "random roles" model, which depicts males as being favored by some females and disfavored by others, but not to a "constant-type" model, in which a male is either favored or disfavored uniformly by all females in a population.

Animals↗
PubMed1986

Fertility, fecundity, sex ratio and the accessory sex glands in male golden hamsters.

The ventral prostates, dorsolateral prostates, coagulating glands (anterior prostates), ampullary glands and/or seminal vesicles of male golden hamsters were excised bilaterally. The effects of these treatments on fertility, fecundity and sex ratio of offspring were studied. Total removal of the glands or ablation of the ventral prostates alone reduced fertility. The lack of secretions from the coagulating glands and seminal vesicles in the seminal fluid all favoured a higher proportion of male pups born in a litter. Absence of all or any of these glands did not appear to affect litter size.

Animals↗
PubMed1988

Anti-mosquito antibodies and their effects on feeding, fecundity and mortality of Aedes aegypti.

Anti-mosquito antibodies, produced in mice inoculated with mosquito homogenates or exposed to mosquito bites, reacted with a variety of mosquito antigens including muscle, gut, fat body and nervous tissue; those in anti-mosquito bite sera reacted solely with salivary glands. Mosquitoes fed on restrained immunized mice showed a significant increase in mortality correlated to both the titre and specificity of the anti-mosquito antibodies ingested. No changes in their fecundity or feeding success were noted. Mosquitoes exposed to unrestrained immunized mice or mosquito-bitten mice, however, showed a significant reduction in feeding success, possibly reflecting enhanced host grooming.

Aedes↗
PubMed1996

Effects of variations in a formulated protein meal on the fecundity and fertility of female mosquitoes.

A formulated protein meal developed by Kogan (1990) for adult female Aedes aegypti mosquitoes was evaluated and modified to increase egg and pupal yield. A vigorous laboratory colony was maintained with the females fed exclusively on this dietary formula for about twenty-five generations over more than 2 years. Extra modifications were made to produce a diet suitable for Anopheles arabiensis and Anopheles stephensi females to produce eggs. Both formulations contain bovine albumin, haemoglobin and globulin in a ringer based solution, plus ATP as a phagostimulant for Ae.aegypti. Compared to Kogan's original, our Aedes formula doubled the production of pupae per female after a single meal, although the yield was still significantly lower than from mosquitoes fed on animal hosts or defibrinated pig blood. In varying the proportions of different constituents during attempts to optimize the formula, no relationship was found between total protein content (within the range 80-220 mg/ml) and fecundity, percentage hatch or pupal yield of Ae.aegypti. Equivocal results were found when an isoleucine supplement was added to the formula.

Aedes↗
PubMed1995

Regulation of egg production, worm burden, worm length and worm fecundity by host responses in sheep infected with Ostertagia circumcincta.

Following infection with Ostertagia circumcincta there was considerable variation in worm burdens, worm size and number of inhibited larvae even among sheep matched for age, sex, breed, farm of origin and history of parasite exposure. There was also substantial variation among sheep in the concentration of mast cells, globule leucocytes, eosinophils, IgA-positive plasma cells and parasite-specific IgA in the abomasal mucosa. With the exception of faecal egg counts over time, the parasitological and immunological traits were all continually distributed among animals and sheep did not fall into discrete high and low-responder categories. The responses were correlated. Sheep with more mast cells also had more globule leucocytes, more eosinophils, more IgA plasma cells and greater amounts of parasite-specific IgA in the abomasal mucosa. Female worm length was strongly and positively correlated with the number of eggs in utero. Faecal egg counts were associated with variation in worm number and with variation in the number of eggs in utero. The worm burden was negatively correlated with the number of globule leucocytes in the abomasal mucosa, suggesting that worm numbers are regulated by immediate hypersensitivity reactions. Decreased female worm length was associated with an increased local IgA response to fourth stage larvae. The number of inhibited larvae was positively associated with the size of the local IgA response and positively associated with the size of the worm burden. The results suggest that variation among mature sheep in faecal egg counts is due, at least in part, to variation in local IgA responses which regulate worm fecundity and to variation in local immediate hypersensitivity reactions which regulate worm burdens.

Animals↗
PubMed1975

Investigation on Huntington's disease in the Canadian Prairies. II. Fecundity and fitness.

The reproductive performance of 157 patients with Huntington's disease, their 170 normal siblings and 150 matched unrelated controls is presented. Comparison with the general Canadian Prairie population in the appropriate age group is undertaken. Patients with Huntington's disease are not only more fecund than their unaffected sibs but also out-reproduce unrelated normal controls and members of the general population of corresponding age. Their fitness is thus estimated to be 1.14. Should the present reproductive pattern continue, the allele for Huntington's disease will double its frequency with consequent doubling of the prevalence of the disorder in six generations or approximately 150 years' time.

Female↗