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PubMed1982

[Advantages and risks of hormonal contraception].

Among modern contraceptive methods hormonal contraceptive agents, due to their reliability, are preferred. Nevertheless, it has to be considered that these steroidal hormones and their metabolites do not only possess an ovulation inhibitory effect, but that they also influence other systems, such as carbohydrate and lipid metabolism, blood clotting, fluid balance, plasma proteins as well as the entire hormonal system. These multiple side effects have positive and negative influences. By reducing the doses of estrogens and progestagens occurrence of unpleasant adverse reactions has been decreased. Some years ago, the estrogen content of oral contraceptive preparations was considered to be noxious while a favourable effect was attributed to the progestagen content. The results of biochemical studies yielded a better understanding of the effect of steroidal hormones on lipid metabolism. Fertility problems occurring after discontinuation of oral contraceptive treatment are mainly observed in women who, prior to use of oral contraceptive agents have already been suffering from functional cycle disturbances. Ovulation inhibitory preparations may also be given to adolescent girls with immature cycles. As the juvenile endocrine system is adaptable, after cessation of the ovulation inhibitory effect, the cycle returns to pretreatment patterns. It may now even be possible to administer hormonal contraceptive agents to treat endocrine disturbances.

Adult↗
PubMed2001

Beyond reinforcement: the evolution of premating isolation by direct selection on preferences and postmating, prezygotic incompatibilities.

The evolution of premating isolation after secondary contact is primarily considered in the guise of reinforcement, which relies on low hybrid fitness as the driving force for mating preference divergence. Here I consider two additional forces that may play a substantial role in the adaptive evolution of premating isolation, direct selection on preferences and indirect selection against postmating, prezygotic incompatibilities. First, I argue that a combination of ecological character displacement and sensory bias can cause direct selection on preferences that results in the pattern of reproductive character displacement. Both analytical and numerical methods are then used to demonstrate that, as expected from work in single populations, such direct selection will easily overwhelm indirect selection due to low hybrid fitness as the primary determinant of preference evolution. Second, postmating, prezygotic incompatibilities are presented as a driving force in the evolution of premating isolation. Two classes of these mechanisms, those increasing female mortality after mating but before producing offspring and those reducing female fertility, are shown to be identical in their effects on preference divergence. Analytical and numerical techniques are then used to demonstrate that postmating, prezygotic factors may place strong selection on preference divergence. These selective forces are shown to be comparable if not greater than those produced by the low fitness of hybrids.

Animals↗
PubMedDate not supplied

Patterns of contraceptive use in China.

This article uses demographic and contraceptive use data from China's 1982 census, 1982 national fertility survey, and National Family Planning Commission to examine the country's patterns of reproductive and contraceptive behavior. Although China's fertility is near replacement level, it varies considerably among the country's subregions. One-half of all 15-49-year-old married fecund women who practice contraception are using intrauterine devices (IUDs); this means that about 70 percent of the world's IUD users are in China. Although China and the United States have similar overall contraceptive use rates, pronounced differences exist regarding the types of contraceptive methods used. Among China's subregions, contraceptive use rates vary considerably. The greater the percentage of minority groups in a subregion, the lower its contraceptive prevalence rate. The lower the proportion urban in an area, the greater the use of the IUD, except in areas with large numbers of minorities. Among the subregions, associations between urban/health variables and pill/condom use rates are strongly positive, and associations between urban/health variables and IUD use rates are strongly negative.

Adolescent↗
PubMed1997

Analysis of unfertilized oocytes subjected to intracytoplasmic sperm injection using two rounds of fluorescence in-situ hybridization and probes to five chromosomes.

Chromosomal aberrations are the major cause of pre- and post-implantation embryo wastage and some studies suggest that half of all human conception have a chromosomal abnormality. Analysis of gametes provides information on the origin of these chromosomal aberrations. The purpose of this study was to develop a reliable multi-probe fluorescence in-situ hybridization (FISH) procedure that would enable us to investigate aneuploidy in unfertilized oocytes subjected to intracytoplasmic sperm injection (ICSI). Oocytes were spread with HCl and Tween 20 solution, and then two rounds of triple-probe FISH were performed on each oocyte using directly-labelled centromeric probes: chromosomes 1, 7, 15 (overnight hybridization); chromosomes 1, X, Y (2 h hybridization). After the first round, the slides were counterstained and evaluated, and the positions of FISH signals were recorded. For the second round, the counterstain was removed and the second probe cocktail was applied. The chromosome 1 probe was an internal control for the two hybridization procedures, while the Y chromosome probe was used to detect sperm DNA. To evaluate the method, a total of 79 oocytes from 27 patients were studied. Of these, 67 (84.8%) were successfully spread and 97% of these oocytes exhibited discernible FISH signals. Upon lysis, oocytes exhibited one or more DNA fragments (mean 1.9, range 1-3). Of the 65 analysable oocytes, 17 (26.2%) displayed a normal haploid chromosome constitution with paired spots for the two chromatids. A further 23 oocytes (35.4%) showed an ambiguous chromosome complement due to an abnormal number of DNA fragments which may have resulted from loss of DNA during spreading or to an abnormal oocyte, while 25 oocytes (38.4%) displayed aneuploidy for one or more of the chromosomes studied. In conclusion, this new approach is a quick and efficient method with which numerical chromosomal abnormalities in human oocytes can be studied; interpretation of the patterns of DNA fragments and FISH signals requires further clarification.

Aneuploidy↗
PubMed2006

On the politics and practice of Muslim fertility: comparative evidence from West Africa.

Recent popular works have represented Muslim fertility as dangerously high, both a cause and consequence of religious fundamentalism. This article uses comparative, statistical methods to show that this representation is empirically wrong, at least in West Africa. Although religion strongly inflects reproductive practice, its effects are not constant across different communities. In West African countries with Muslim majorities, Muslim fertility is lower than that of their non-Muslim conationals; in countries where Muslims are in the minority, their apparently higher reproductive rates converge to those of the majority when levels of education and urban residence are taken into account. A similar pattern holds for infant mortality. By contrast, in all seven countries, Muslim women are more likely to report that their most recent child was wanted. The article concludes with a discussion of the relationship between autonomy and fertility desires.

Adult↗
PubMed1981

The return of fertility following discontinuation of oral contraceptives in Thailand.

The return of fertility following discontinuation of oral contraception was studied in a survey of 437 Thai women who stopped taking the pill to have a planned pregnancy. Conception rates were reduced during the first 2 months after stopping the pill, and the median delay prior to conception was approximately 3 months. This delay was shorter for nulligravid women. Most women (94.3%) became pregnant within 2 years of stopping the pill. There was a cyclic pattern in the monthly pregnancy rates with peak rates around 3 and 6 months after discontinuing contraception. These findings are similar to those reported for Caucasian women.

Adult↗
PubMedDate not supplied

Trends in contraceptive use in the United States: 1982-1995.

CONTEXT: Trends in contraceptive use have implications for shifts in pregnancy rates and birthrates and can inform clinical practice of changes in needs for contraceptive methods and services. METHODS: Information on current contraceptive use was collected from a representative sample of women of reproductive age in the 1995 National Survey of Family Growth (NSFG). This information is compared with similar data from 1982 and 1988 to examine trends in use, both overall and in social and demographic subgroups. RESULTS: The proportion of U.S. women using a contraceptive method rose from 56% in 1982 to 60% in 1988 and 64% in 1995. As in 1982 and 1988, female sterilization, the pill and the male condom were the most widely used methods in 1995. Between 1988 and 1995, the proportion of users relying on the pill decreased from 31% to 27%, while condom use rose from 15% to 20%. The largest decreases in pill use and the largest increases in condom use occurred among never-married women and among black women younger than 25. Reliance on the IUD dropped sharply among Hispanic women, while use of the diaphragm fell among college-educated white women. CONCLUSIONS: The decline in pill and diaphragm use and the increase in reliance on condoms suggest that concerns about HIV and other sexually transmitted diseases are changing patterns of method use among unmarried women.

Adolescent↗
PubMed1996

Isozyme Variation among Biological Species in the Gibberella fujikuroi Species Complex (Fusarium Section Liseola).

Isozyme phenotypes were determined for 101 strains of Gibberella fujikuroi and 2 strains of Gibberella nygamai that represent seven biological species (mating populations) isolated from a variety of plant hosts in dispersed geographic locations. Fourteen enzymes were resolved in one or more of three buffer systems. Two of the enzymes, arylesterase and acid phosphatase, were polymorphic within two or more biological species and are suitable for intraspecific studies of population variation. Six enzymes, alcohol dehydrogenase, aspartate aminotransferase, glucose-6-phosphate dehydrogenase, mannitol dehydrogenase, phosphoglucomutase, and phosphogluconate dehydrogenase, were monomorphic in all of the isolates examined. The remaining six enzymes, fumarase, glucose phosphate isomerase, glutamate dehydrogenase (NADP), isocitrate dehydrogenase (NADP), malate dehydrogenase, and triose-phosphate isomerase, could potentially be used to distinguish the different biological species. Mating populations C and D are the most similar, since the mating population C isolates examined had the same isozyme phenotype as did a subset of the isolates in mating population D. Mating population E is the least similar to the other taxa examined. Unique isozyme phenotypes are present but are composed of banding patterns shared among the biological species. This finding supports the hypothesis that these biological species, with the possible exception of mating populations C and D, are reproductively isolated from one another and that no significant gene flow is occurring between them. Isozyme analysis is a useful method to distinguish these closely related biological species. Examination of isozyme phenotypes is more rapid than the present technique, which is based on sexual crosses; can be applied to strains that are not sexually fertile; and is more sensitive than traditional morphological characters, which cannot distinguish more than three or four morphological groups among the seven biological species. While emphasizing the discreteness of the mating populations as biological entities, our isozyme data also reaffirm the close genetic relationship among these groups.

Journal Article↗
PubMed2026

Gut Dysbiosis in Selected Gynecological Diseases Associated with Female Infertility: A Scoping Review.

Background/Objectives: Female infertility represents a significant public health issue. Available evidence supports the hypothesis that the gut microbiota may play an essential role in women's reproductive health and may serve as a diagnostic or prognostic biomarker in specific gynecological disorders. A substantial part of current research concerns disturbed communication between the hypothalamic-pituitary-ovarian axis and the gut microbiota, providing the basis for analyzing this phenomenon as the gut-ovary axis or the gut-vagina-ovary axis. The primary aim of this scoping review was to map the available evidence on the relationship between gut microbiota composition and female infertility, with particular emphasis on polycystic ovary syndrome (PCOS, currently polyendocrine metabolic ovarian syndrome, PMOS) endometriosis, and uterine fibroids. Methods: The review was conducted in accordance with the PRISMA Extension for Scoping Reviews (PRISMA-ScR). PubMed, Scopus, and Google Scholar were searched using terms related to gut microbiota, female infertility, PCOS, endometriosis, and uterine leiomyomas. Peer-reviewed publications in English published between 2015 and 2025 were considered. The included studies were descriptively synthesized to identify recurring microbiota patterns and research gaps. Results: The reviewed evidence indicates that gut dysbiosis may be associated with selected gynecological disorders affecting fertility, including PCOS, endometriosis, and uterine fibroids. The gut microbiome may have potential value as a biomarker supporting diagnosis, treatment selection, and prognosis. Conclusions: The gut microbiome represents a promising but still insufficiently validated area in the management of gynecological diseases associated with female infertility. Further high-quality clinical studies are needed to verify the effectiveness of microbiome-based therapies and to develop evidence-based guidelines for managing infertility associated with gut dysbiosis.

dysbiosis↗
PubMed2005

Ocular growth in premature infants conceived by in vitro fertilization versus natural conception.

PURPOSE: To evaluate the possible effect of in vitro fertilization (IVF) on early development of the eye in premature infants. METHODS: Biometric and keratometric values, intraocular pressure, and retinal vascular status were assessed in a cohort of 133 premature infants. These values were compared between premature infants conceived by IVF or naturally, and the relationship between these parameters and postconceptional age and weight at examination were evaluated. RESULTS: The sample consisted of 133 premature infants, 62 (46.6%) born by IVF and 71 (53.4%) by natural conception. Postconceptional age at examination was 28 to 46 weeks. In both groups, axial length, anterior chamber depth, and corneal radius correlated with the postconceptional age and weight at examination and followed a linear growth pattern. Lens thickness changed very slightly. The rate of retinal vascularization correlated with the postconceptional age as well. No correlation was found between intraocular pressure and corrected age or weight at examination. There was no difference between the study and control groups in any of the biometric or keratometric parameters or in intraocular pressure, according to two-way analysis of variance. CONCLUSIONS: IVF apparently does not affect early ocular growth, intraocular pressure, changes in corneal curvature, or retinal vascularization in premature infants. These findings may aid ophthalmologists in assessing ocular dimensions in this patient population.

Biometry↗
PubMed1992

Breast-feeding alters LH secretion pattern.

The contraceptive effects of breast feeding are probably due to the marked changes which suckling causes in the pattern of luteinizing hormone (LH) secretion, studies conducted in Scotland have shown. In mothers who fully breast feed their babies, these changes are sufficient to offer contraceptive protection of 98% for about 6 months postpartum. Breast feeding mothers should start to use another method of contraception 6 months after giving birth, or after they start supplementing breastfeeds with other food, or after the 1st menses, a plenary session on breast feeding, birth spacing, and child survival heard. The researchers from Scotland also presented striking new evidence of the protective effect of breast feeding on the heaLth of newborn babies. The studies were conducted in Edinburgh and Dundee over a period of more than 10 years and covered a range of different aspects of breast feeding and fertility. Dr. Anna Glasier, who presented findings on the hormonal changes which occur in breast feeding women, showed that suckling postpones the return of ovarian activity after childbirth. The results for 1 mother who bottle fed her baby showed that menstruation returned as early as 6 weeks postpartum, ovulation occurred at 10 weeks, and that by 14 weeks, a normal ovarian cycle had returned. In a group of 27 breast feeding mothers, the onset of ovarian activity was found to coincide with the introduction of solid food and a decline in suckling activity. In many cases, ovulation suppressed for several months after supplementation of breast feeding began and a normal ovarian cycle did not return until well after breast feeding had been stopped completely. Dr. Glasier said all the women studied showed marked disturbances of the pulsatile pattern of LH secretion, which gradually returned to normal as suckling declined. The disturbance is thought to be caused by the effect of suckling on the hypothalamic pulse generator, although the mechanism by which this occurs is not yet understood, she said. The Scottish researchers believe that it is this disturbance which is responsible for the contraceptive effect of breast feeding. Their findings appear to disprove the theory that ovarian suppression is due to the increased levels of prolactin which occur during breast feeding. Dr. Glasier explained that the administration of exogenous GnRH restored normal LH secretion patterns and ovarian activity in women who were fully breast feeding their babies, despite the presence of elevated prolactin concentrations. Her fellow-researcher Prof. Peter Howie presented the findings of a study of 750 Dundee mothers and their babies, aimed at examining the effects of breast feeding on the infants. Because most previous studies have been criticized as methodologically flawed, the Dundee investigation was carefully designed to meet important methodological criteria. Prof. Howie told the meeting that in the babies who were bottle fed or weaned before 13 weeks, gastrointestinal illness was 5-8 times more common than in babies who were breast fed for longer. The rate of illness among the babies breast fed for less than 13 weeks the close to that in some developing countries. The protective effect of breast feeding persisted beyond the period of breast feeding itself up to 1 year of life. These data support the view that breast feeding of offers important health benefits to babies in all environments, she said.

Biology↗
PubMed2006

[Glycodelin in IVF-ET cycles: its association with endometrial receptivity and impact on the outcome of pregnancy].

OBJECTIVE: To investigate the correlation between glycodelin and endometrial receptivity and the value of serum glycodelin detection in in vitro fertilization and embryo transfer (IVF-ET) cycles for evaluation of the outcome of pregnancy. METHODS: Serum glycodelin level in women receiving IVF-ET on the day of oocyte retrieval and embryo transfer was measured by ELISA, and the condition of the endometrium was examined by transvaginal ultrasonography. RESULTS: There was no difference in serum glycodelin level on the day of oocyte retrieval or embryo transfer between the pregnant group and nonpregnant group, but the ratio and difference of serum glycodelin levels on the days of embryo transfer and retrieval were both higher in pregnant group than in the nonpregnant group (2.54-/+2.14 vs 0.96-/+0.51, and 0.91-/+1.22 vs -0.30-/+1.14, respectively). No correlation was found between serum glycodelin levels and endometrial thickness or echo patterns. CONCLUSION: Serum glycodelin levels on the days of retrieval and embryo transfer are not correlated to endometrial thickness or echo patterns, but their dynamic changes reflect endometrial receptivity to a certain extent, which might have prognostic value for pregnancy following IVF-ET.

Adult↗
PubMed1986

Recognition and treatment of immune disorders at the time of birth.

Neonatal immunology offers a fertile field for the investigator. Not only does it supply a great deal of information about immunology in general, but it also presents challenges peculiar to this critical period of life. The complement, phagocytic, antibody, and T cell systems in the neonate have characteristic defects and inadequacies. The genetic conditions that compromise the newborn's immune system are discussed in terms of clinical manifestations as well as laboratory abnormalities. In addition, patterns that may suggest the presence of immunodeficiency are described. Finally, methods of managing the immunodeficient infant are outlined, including clinical and laboratory modalities.

Adenosine Deaminase↗
PubMed1978

Clearing, cuticle removal, and staining for the fertile bracts (lemmas and paleas) of grass anthoecia.

The epidermis of the bracts enclosing the flower of grasses contains epidermal cell patterns which are indicative of phylogenetic and systematic relationships among taxa. Treating the heavily cutinized anthoecial bracts (fertile lemma and palea) with 10% NaOH results in the removal of sufficient cuticle to allow examination of the cells of the epidermis. After clearing and removal of the cuticle, the bracts are bleached, washed, dehydrated, and if studied by light microscopy, stained in 2% chlorazol black E and mounted in Diaphane; or, if studied by scanning electron microscopy, dried by the critical-point method and either left uncoated or coated with a film of various conductive metals.

Histological Techniques↗
PubMed2006

Statistical modelling of the seasonality of preterm delivery and intrauterine growth restriction in rural Gambia.

We have developed a methodology for comparing the seasonal influences on two outcomes, when those influences may act cumulatively or instantaneously. We have used this to compare the seasonal pattern of intrauterine growth retardation (IUGR, as reflected by weight-for-gestational-age) and preterm delivery (as assessed by Dubowitz scoring) among 1718 infants born in rural Gambia. Both outcomes were analysed as binary variables: small-for-gestational-age (SGA, <10th centile of reference standard) and preterm (<37 weeks) respectively. Percentages of preterm and SGA babies show divergent seasonal patterns that might indicate separate aetiologies. However, seasonal effects influencing intrauterine growth are likely to be cumulative over the last few months of pregnancy. By modelling seasonality with truncated Fourier series we were able to deconvolve the underlying seasonal influences on fetal growth from the pattern for SGA. This enabled us to use seemingly unrelated biprobit regression to compare the underlying seasonal pattern of intrauterine growth with that governing the incidence of preterm delivery. We conclude that, if the seasonal factors affecting intrauterine growth operate over more than the last 2 months of pregnancy, then the seasonal patterns of the factors causing IUGR and preterm delivery are indistinguishable if the factors are assumed to trigger preterm delivery immediately, but differ if preterm delivery is assumed to be programmed by factors acting at conception.

Epidemiologic Methods↗
PubMed2002

Postchemotherapy ejaculatory azoospermia: fatherhood with sperm from testis tissue with intracytoplasmic sperm injection.

PURPOSE: To define the success of testis sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI) in azoospermic men with a history of chemotherapy. PATIENTS AND METHODS: In a retrospective study, 23 men with ejaculatory azoospermia and a history of chemotherapy underwent TESE in a search for usable spermatozoa. In six patients cryopreserved tissue and in nine patients fresh tissue provided sperm for an ICSI cycle. Histologic analysis of the testis was performed in all patients. The presence or absence of sperm, fertilization rates with ICSI, and final outcomes of pregnancy were recorded. RESULTS: Spermatozoa were found on TESE in 15 (65.2%) of 23 men. On histopathology, the predominant pattern observed was Sertoli cell only (47.8%), followed by hypospermatogenesis (30.4%), mixed (17.4%), and late maturation arrest (4.3%). The fertilization rate was 65.2%, and ongoing/delivered pregnancies occurred in 30.8% of cycles. Six healthy boys and four healthy girls have been born to date. CONCLUSION: Men who are azoospermic and have had prior cytotoxic therapy make up a small subgroup of males with nonobstructive azoospermia. It is important to define and characterize this subgroup and better define their true fertility potential. Approximately two thirds of these men have retrievable testis sperm, which may be used with ICSI to have healthy offspring. This exciting avenue for paternity has heretofore not been available to such patients.

Adolescent↗