scholarly journals Ovulation Patterns Affect the Offspring Sex Ratios and Change With the Women’s Age

2021 ◽  
Author(s):  
Misao Fukuda ◽  
Kiyomi Fukuda ◽  
Shawn Mason ◽  
Kenichi Tatsumi ◽  
Takashi Shimizu ◽  
...  
Keyword(s):  
Intrauterine Insemination ◽  
Sex Ratios ◽  
Male Offspring ◽  
Offspring Sex Ratio ◽  
Menstrual Cycles ◽  
Younger Women ◽  
Infertile Women ◽  
Significant Difference ◽  
Offspring Sex ◽  
Fertile Women

Abstract Purpose The aim of this study was to evaluate whether women’s ages at conception and the ratio of male to female infants are associated with various ovulation patterns.Methods An observational clinical study was conducted in private OB/GYN clinics. Infertile women with regular menstrual cycles receiving intrauterine insemination (IUI) and/or in-vitro fertilization (IVF) had their ovulation patterns monitored in three consecutive spontaneous cycles receiving infertility treatment in the third cycle. Ovulation patterns were also observed in women with slight ovulation disorders during IUI and/or IVF in clomiphene citrate stimulated cycles. All the pregnant women’s ages at conception and their respective offspring sex ratios were compared to various ovulation patterns. Results Contralateral ovulation (i.e. ovulation jumping from ovary to the other) was more often observed in relatively younger women, who showed a higher probability of having a boy than after ipsilateral ovulation. There was a significantly higher frequency of boys being conceived following three consecutive ovulations with a left-left-right (LLR) ovulation pattern, while three ovulations from the left ovary (LLL) were associated with a higher frequency of girls. We also found two consecutive menstrual cycles the left-right (LR) ovulation pattern showed a similar significant difference compared to the left-left (LL) ovulation. Both the infertile and infertile + fertile women groups showing right-sided ovulation, regardless of age, showed significantly higher offspring sex ratio compared to left-sided ovulation, which was not observed in the group of fertile women alone. Conclusions LLR, LR and contralateral ovulation happens more often in younger women and favors male offspring in infertile women. Right-sided ovulation favors male offspring in infertile and infertile + fertile women, which was not observed in the group of fertile women.

scholarly journals Consistent sex ratio bias of individual female dragon lizards

2006 ◽  
Vol 2 (4) ◽  
pp. 569-572 ◽  
Author(s):  
Tobias Uller ◽  
Beth Mott ◽  
Gaetano Odierna ◽  
Mats Olsson
Keyword(s):  
Genetic Variation ◽  
Sex Ratio ◽  
Incubation Temperature ◽  
Sex Ratios ◽  
Phenotypic Traits ◽  
Female Size ◽  
Offspring Sex Ratio ◽  
Phenotypic Differences ◽  
Sex Ratio Bias ◽  
Offspring Sex

Sex ratio evolution relies on genetic variation in either the phenotypic traits that influence sex ratios or sex-determining mechanisms. However, consistent variation among females in offspring sex ratio is rarely investigated. Here, we show that female painted dragons ( Ctenophorus pictus ) have highly repeatable sex ratios among clutches within years. A consistent effect of female identity could represent stable phenotypic differences among females or genetic variation in sex-determining mechanisms. Sex ratios were not correlated with female size, body condition or coloration. Furthermore, sex ratios were not influenced by incubation temperature. However, the variation among females resulted in female-biased mean population sex ratios at hatching both within and among years.

scholarly journals Effects of Letrozole-HMG and Clomiphene-HMG on Incidence of Luteinized Unruptured Follicle Syndrome in Infertile Women Undergoing Induction Ovulation and Intrauterine Insemination: A Randomised Trial

2015 ◽  
Vol 8 (4) ◽  
pp. 244 ◽  
Author(s):  
Azra Azmoodeh ◽  
Mansoureh Pejman Manesh ◽  
Firouzeh Akbari Asbagh ◽  
Azizeh Ghaseminejad ◽  
Zeinab Hamzehgardeshi
Keyword(s):  
Menstrual Cycle ◽  
Endometrial Thickness ◽  
Intrauterine Insemination ◽  
Clomiphene Citrate ◽  
Randomised Trial ◽  
Induction Of Ovulation ◽  
Infertile Women ◽  
Significant Difference ◽  
Preovulatory Follicles ◽  
Luteinized Unruptured Follicle

<p><strong>BACKGROUND: </strong>Luteinized unruptured follicle (LUF) syndrome is considered a cause of ovulation failure and a subtle cause of infertility. Preovulatory injection of human chorionic gonadotropin (HCG) prevents or treats LUF syndrome, but it has also occurred after the induction of ovulation with clomiphene/HMG and HCG. This study was designed for evaluation and comparison of LUF incidence in eligible infertile women undergoing two stimulation protocols (clomiphene + HMG<strong> </strong>and letrozole + HMG) in addition to intrauterine insemination (IUI). Some related factors were compared between LUF and non-LUF cycles as secondary outcomes.</p> <p><strong>METHODS:</strong> The study was designed as a prospective randomized controlled trial. Patients were randomized using a table of random numbers into two equal protocol groups.<strong> </strong>For group A, (n = 90) clomiphene citrate was administrated orally in doses of 100 mg/day, and group B (n = 90) orally received letrozole 5 mg/day from day 3 to 7 of the menstrual cycle. Then HMG 75IU/day was administered intramuscularly in both groups on day 8 of the menstrual cycle and the dose was adjusted on the basis of ovarian response. The optimum size of preovulatory follicles for the injection of HCG (10,000 IU) was considered 18–23 mm. The number and size of preovulatory follicles were assessed by vaginal ultrasound 12 h before HCG (D0). Endometrial thickness was measured as well. IUI was performed on all patients 38–40 h after HCG. The second ultrasound examination was performed to observe the evidence of oocyte releasing at the time of IUI (D1). If the follicles were unruptured,<strong> </strong>a<strong> </strong>third sonography was performed on day 7 after HCG (D7) to observe LUF syndrome.</p> <p><strong>RESULTS: </strong>There was a significant difference between clomiphene-HMG and letrozole-HMG in LUF (p = 0.021) and pregnancy (p = 0.041). The complete LUF in letrozole-HMG was lower than the alternative group and the pregnancy rate was higher. The patients in the non-LUF group had higher midluteal progesterone and a thicker endometrium compared to LUF cycles (p = 0.039) and (p &lt; 0.001). The results of our multivariate logistic regression indicate that size 18–19.9 mm leads to the complete LUF  less than ≥22 mm [AOR: 0.25, P = 0.005], and  in size 20– 21.9 mm  as well [AOR: 0.17, P = 0.002].</p> <p><strong>CONCLUSION: </strong>Letrozole, with lower incidences of LUF, is more effective than clomiphene citrate for the induction of ovulation in IUI cycles. In our study, we illustrated that larger follicles of ≥22 mm diameter were associated with higher incidences of LUF. We recommend that further studies investigate and focus on the relationship between follicular size and/or full hormonal profiles and LUF.<strong></strong></p>

Host size-dependent sex allocation behaviour in a parasitoid: implications forCatolaccus grandis(Hymenoptera: Pteromalidae) mass rearing programmes

1998 ◽  
Vol 88 (1) ◽  
pp. 37-45 ◽  
Author(s):  
K.M. Heinz
Keyword(s):  
Biological Control ◽  
Sex Ratio ◽  
Sex Allocation ◽  
Sex Ratios ◽  
Boll Weevil ◽  
Mass Rearing ◽  
Host Size ◽  
Offspring Sex Ratio ◽  
Offspring Sex ◽  
Control Programmes

AbstractAn often encountered problem associated with augmentative and inundative biological control programmes is the high cost of producing sufficient numbers of natural enemies necessary to suppress pest populations within the time constraints imposed by ephemeral agroecosystems. In many arrhenotokous parasitoids, overproduction of males in mass-rearing cultures inflates costs (per female) and thus limits the economic feasibility of these biological control programmes. Within the context of existing production technologies, experiments were conducted to determine if the sex ratio ofCatolaccus grandis(Burks), an ectoparasitoid of the boll weevilAnthonomous grandisBoheman, varied as a function of boll weevil larval size. Results from natural and manipulative experiments demonstrate the following behavioural characteristics associated with C.grandissex allocation behaviour: (i) femaleC. grandisoffspring are produced on large size hosts and male offspring are produced on small hosts; (ii) whether a host is considered large or small depends upon the overall distribution of host sizes encountered by a female parasitoid; and (iii) female parasitoids exhibit a greater rate of increase in body size with host size than do male parasitoids. The observed patterns cannot be explained by sex-specific mortality of immature parasitoids developing on the different host size categories. In subsequent experiments, laboratory cultures ofC. grandisexposed daily to successively larger sizes ofA. grandislarvae produced successively greater female biased offspring sex ratios, cultures exposed daily to successively smaller sizes of host larvae produced successively greater male biased offspring sex ratios, and cultures exposed daily to equivalent host size distributions over time maintained a uniform offspring sex ratio. By increasing the average size ofA. grandislarval hosts exposed toC. grandisby 2.5 mg per day in mass rearing cultures, the percentage of male progeny can be reduced from 33% to 23% over a period of four consecutive exposure days.

scholarly journals Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

2013 ◽  
Vol 280 (1772) ◽  
pp. 20132460 ◽  
Author(s):  
Timothy S. Mitchell ◽  
Jessica A. Maciel ◽  
Fredric J. Janzen
Keyword(s):  
Sex Ratio ◽  
Sex Determination ◽  
Nest Site ◽  
Sex Ratios ◽  
Temperature Dependent ◽  
Dioecious Species ◽  
Offspring Sex Ratio ◽  
Nest Sites ◽  
Offspring Sex ◽  
Nest Site Choice

Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle ( Chrysemys picta ) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness.

scholarly journals Examination of sexual functions and depressive symptoms among infertile and fertile women

2019 ◽  
Vol 35 (5) ◽  
Author(s):  
Selda Ozturk ◽  
Hatice Kahyaoglu Sut ◽  
Leyla Kucuk
Keyword(s):  
Depressive Symptoms ◽  
Sexual Dysfunction ◽  
Sexual Function ◽  
Sexual Intercourse ◽  
Beck Depression Inventory ◽  
Female Sexual Function ◽  
Cross Sectional ◽  
Infertile Women ◽  
Significant Difference ◽  
Fertile Women

Objective: To examine the sexual functions and depressive symptoms of infertile and fertile women. Methods: This study was conducted between October 2015 and April 2016 using a descriptive, cross-sectional and comparative design. The sample of this study consisted of 96 infertile and 96 fertile women. The data were collected using an information form, the Beck Depression Inventory and the Index of Female Sexual Function. The data were analyzed The Mann-Whitney U test, chi-square test, and Spearman’s correlation analysis. Results: The rate of sexual dysfunction (87.5% vs. 69.8%) and the Index of Female Sexual Function total score (31.8 ± 7.8 vs 35.7 ± 6.3) were significantly higher in infertile women than fertile women (p=0.003, p<0.001, respectively). The sexual satisfaction and discomfort during sexual intercourse subscales of the Index of Female Sexual Function were significantly lower among infertile women than fertile women (p<0.001 for all); however, no significant difference was observed in the sexual intercourse/libido score of the Index of Female Sexual Function between infertile and fertile women (p=0.590). The correlation coefficients between the Beck Depression Inventory total score and the total and subscale scores of the IFSF did not significantly differ between infertile and fertile women (p>0.05 for all). Conclusion: The sexual dysfunction rate among infertile women was higher than that among fertile women. Sexual functions decreased when depressive symptoms increased for both infertile and fertile women. doi: https://doi.org/10.12669/pjms.35.5.615 How to cite this:Ozturk S, Sut HK, Kucuk L. Examination of sexual functions and depressive symptoms among infertile and fertile women. Pak J Med Sci. 2019;35(5):---------. doi: https://doi.org/10.12669/pjms.35.5.615 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Offspring sex ratio and reproductive tactics of Leptocybe invasa (Hymenoptera: Eulophidae): testing the effect of environmental characteristics

2018 ◽  
Vol 38 (04) ◽  
pp. 394-399 ◽  
Author(s):  
Xia-Lin Zheng ◽  
Kai Lin ◽  
Zong-You Huang ◽  
Jun Li ◽  
Zhen-De Yang ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Insect Pest ◽  
Thermal Acclimation ◽  
Reproductive Tactics ◽  
Environmental Characteristics ◽  
Offspring Sex Ratio ◽  
Significant Difference ◽  
Offspring Sex ◽  
Leptocybe Invasa ◽  
D 12

AbstractEnvironmental characteristics (for example, temperature, photoperiod) as seasonal cues can affect the offspring sex ratio and reproductive tactics of many hymenopteran insects. Leptocybe invasa Fisher &amp; La Salle is the most critical invasive insect pest of Eucalyptus spp. in the world and displays thelytokous reproduction. In the current study, we studied the effects of temperature and photoperiod on offspring sex ratio and reproductive tactics in L. invasa. Results show that sex ratio (female: male) of L. invasa was under 15, 25 and 35 °C with both L 12: D 12 and L 16: D 8, and cold and thermal acclimation were 74.5:1, 71.0:1, 59.0:0, 17.3:1, 53.0:0, 64.0:0, 47.0:1 and 56.0:0, respectively, which was highly significantly female biased and with no significant difference due to temperature or photoperiod. Offspring virgin females oviposited and induced the bump-shaped galls on plants under the same conditions as described above. Constant temperature, photoperiod and their interaction, and cold and thermal acclimation had no significant effect on the infestation rates of Eucalyptus branches induced by offspring virgin females. Thus, temperature, photoperiod and cold and thermal acclimation did not influence female-biased sex ratio and tactics with thelytokous reproduction of offspring females in L. invasa.

scholarly journals Drivers of sex ratio bias in the eastern bongo: lower inbreeding increases the probability of being born male

2019 ◽  
Vol 286 (1902) ◽  
pp. 20190345 ◽  
Author(s):  
Aurelio F. Malo ◽  
Tania C. Gilbert ◽  
Philip Riordan
Keyword(s):  
Sex Ratio ◽  
Inbreeding Depression ◽  
Sex Ratios ◽  
Reproductive Traits ◽  
Genetic Effects ◽  
Equal Proportion ◽  
Paternal Effects ◽  
Offspring Sex Ratio ◽  
Genetic Quality ◽  
Offspring Sex

Parent sex ratio allocation has consequences for individual fitness, population dynamics, and conservation. Theory predicts that parents should adjust offspring sex ratio when the fitness returns of producing male or female offspring varies. Previous studies have assumed that only mothers are capable of biasing offspring sex ratios, but have neglected fathers, given the expectation of an equal proportion of X- and Y-chromosome-bearing (CBS) sperm in ejaculates due to sex chromosome segregation at meiosis. This assumption has been recently refuted and both paternal fertility and paternal genetic quality have been shown to bias sex ratios. Here, we simultaneously test the relative contribution of paternal, maternal, and individual genetic quality, as measured by inbreeding, on the probability of being born a son or a daughter, using pedigree and lifelong offspring sex ratio data for the eastern bongo ( Tragelaphus eurycerus isaaci ). Our models showed first, that surprisingly, as individual inbreeding decreases the probability of being born male increases, second, that paternal genetic effects on sex ratio were stronger than maternal genetic effects (which were absent). Furthermore, paternal effects were opposite in sign to those predicted; father inbreeding increases the probability of having sons. Previous paternal effects have been interpreted as adaptive due to sex-specific inbreeding depression for reproductive traits. We argue that in the eastern bongo, the opposite sign of the paternal effect on sex ratios results from a reversed sex-specific inbreeding depression pattern (present for female but not male reproductive traits). We anticipate that this research will help stimulate research on evolutionary constraints to sex ratios. Finally, the results open a new avenue of research to predict sex ratio allocation in an applied conservation context. Future models of sex ratio allocation should also include the predicted inbreeding level of the offspring and paternal inbreeding levels.

Endogenous Corticosterone Elevations Five Hours Prior to Ovulation do not Influence Offspring Sex Ratios in Zebra Finches

2016 ◽  
Vol 9 (3) ◽  
pp. 131-138 ◽  
Author(s):  
A.E. Gam ◽  
K.J. Navara
Keyword(s):  
Sex Ratio ◽  
Sex Ratios ◽  
Zebra Finches ◽  
Meiotic Segregation ◽  
Offspring Sex Ratio ◽  
Handling Stress ◽  
Offspring Sex ◽  
Baseline Corticosterone ◽  
Underlying Mechanisms ◽  
Heterogametic Sex

Previous research suggests that environmental and social factors can drive female birds to bias offspring sex ratios. The underlying mechanisms controlling these adjustments remain unclear. Results from experimental and correlative research suggest that maternal corticosterone plays an important role in this process. Since females are the heterogametic sex in birds, corticosterone may potentially bias offspring sex ratios during meiotic segregation, through non-random segregation of sex chromosomes. In a previous study, we showed that pharmacological elevations of corticosterone near the time of meiotic segregation exerted an effect on offspring sex ratio, causing female Zebra Finches ( Taeniopygia guttata) to produce significantly more males. Here, we aimed to determine whether endogenous elevations in the physiological range have similar effects on offspring sex. First we examined offspring sex ratio in relation to baseline corticosterone levels to determine if natural variation in circulating corticosterone near the time of meiotic segregation is related to offspring sex ratio. Next, we used a 5-minute bag handling protocol to induce corticosterone elevations 5 hours prior to ovulation. Maternal baseline corticosterone levels did not correlate with average clutch sex ratios. In addition, the sex ratios produced by females exposed to handling stress did not differ from sex ratios produced by unmanipulated females. Together these results suggest that physiological levels of endogenous corticosterone, both baseline and acutely elevated near the time of sex determination may not be involved in the adjustment of primary sex ratios in Zebra Finches.

Impact of feeding experiences on oviposition and sex allocation of Neoseiulus californicus (Acari: Phytoseiidae)

2021 ◽  
Author(s):  
Zhong Qiu Xie ◽  
Jia Le Lv ◽  
En Dong Wang ◽  
Xue Nong Xu
Keyword(s):  
Frankliniella Occidentalis ◽  
Prey Species ◽  
Neoseiulus Californicus ◽  
Female Adult ◽  
Offspring Sex Ratio ◽  
Egg Hatch ◽  
Hatch Rate ◽  
Feeding Experience ◽  
Significant Difference ◽  
Offspring Sex

Feeding experiences of predators during immature and adult stages may impact females’ reproduction. In the present study, we investigated reproductive performances of Neoseiulus californicus when both parents had different feeding experiences on Tetranychus urticae and Frankliniella occidentalis. Female and male immatures fed on either prey species. Each newly emerged female adult individually mated with a male had either the same or different feeding experience. Prey for mated females were either same as or different from that consumed during their immature stages. Therefore, eight reproductive treatments were created. The highest cumulative fecundity (57.5±3.3 eggs/female) was observed when both female and male fed on T. urticae with the lowest fecundity (34.2±2.7 eggs/female) observed when the parents fed on F. occidentalis. Daily fecundity and oviposition duration were mainly affected by prey of mated females. Mated females preyed on T. urticae had 56.6% higher daily fecundity and 22.3% shorter oviposition duration than those preyed on F. occidentalis. No significant difference in offspring sex ratio and egg hatch rate was detected between treatments. About 88% of the first-laid eggs developed to males. Impact of prey species consumed by male immatures was only observed on pre-oviposition duration. The average pre-oviposition duration of females who mated with males fed on T. urticae in their immaturity was 33.0% shorter than those females who mated with males fed on F. occidentalis in their immaturity. Results of the present study are valuable in optimizing N. californicus field release strategies, and will help further investigations into the nutritional requirements of this species.

scholarly journals Age-Dependent Constraints of Sex Allocation in a Parasitoid Wasp

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Takatoshi Ueno
Keyword(s):  
Sex Ratio ◽  
Sex Ratios ◽  
Parasitoid Wasp ◽  
Maternal Control ◽  
Offspring Sex Ratio ◽  
Female Age ◽  
Physiological Constraints ◽  
Offspring Sex ◽  
Age Dependent ◽  
Control Failure

The offspring sex ratios of parasitoid wasps often depend on the age of ovipositing females. Physiological constraints such as sperm depletion and senescence are a likely cause. Also, maternal control in response to female age may be an alternative explanation. Here valvifer or abdominal tip movements were used to assess whether age-dependent sex ratio was due to physiological constraints or maternal control with an ichneumonid wasp,Pimpla nipponica; the offspring sex ratio at the time of wasp emergence was compared with the sex ratio predicted from abdominal tip movements. When the female was relatively young, there was little difference between the sex ratios examined. However, as the age of the females increased, the realized offspring sex ratio at wasp emergence was more male-biased than the sex ratio predicted at the time of oviposition. Thus, there was an inconsistency between the sex ratios. Curiously, the predictions of continuous movements for male egg deposition were always perfect, regardless of maternal age; fertilization control failure was detected when the females had decided to lay female eggs. Thus, physiological constraints are a likely explanation for the inconsistency in relation to female age forP. nipponica.

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