Determination of sex ratio of spermatozoa with a deoxyribonucleic acid-probe and quinacrine staining: a comparison.

OBJECTIVE: To evaluate sex selection of spermatozoa. DESIGN: A deoxyribonucleic acid (DNA) probe (pDP34) detecting distinguishable loci on both X and Y chromosome was used to validate the quinacrine-staining method that is often used for determination of the percentage of Y-bearing sperm. Sperm samples were centrifuged over Percoll to obtain samples with a high X:Y ratio according to the quinacrine-staining method. Controls (sperms before processing over Percoll) and processed sperms were subjected to DNA extraction and analysis with the DNA probe. RESULTS: The DNA analysis revealed a 1.0 X:Y ratio of the spermatozoa before and after Percoll separation. CONCLUSION: We conclude that the quinacrine method is not suitable for evaluation of methods that claim to separate X and Y-bearing sperm.

Human cervical mucus and its mucous glycoprotein during the menstrual cycle.

Human cervical mucus was collected serially during the menstrual cycles of each of 10 healthy women. After fractionation by equilibrium density centrifugation in CsCl, the sugar composition of the fractions containing mucous glycoprotein (MG) was examined by gas-liquid chromatography. No cyclic variations were detected in the sugar composition of MG (including sialic acid) or in its electrophoretic behavior. The composition of the mucus varied greatly during the cycle. Near ovulation the ratio of proteins to MG was minimal. During the luteal phase this ratio rose quickly. The secretion of MG was high during ovulation. The concentrations of the other proteins. The composition of cervical proteins was mapped by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

PIP: Cervical mucus samples were obtained serially from 10 married women during their menstrual cycles. The samples were fractionated by equilibrium density centrifugation in CsCl. Sugar composition of the fractions containing mucus glycoprotein (MG) was analyzed by gas-liquid chromatography. Analysis of the purified MG revealed no systematic variations in sugar composition as determined by GLC. Because a constant level of bound sialic acid relative to other sugars was observed, the remarkable changes in the rheology of the mucus content cannot be explained by changes in MG-bound sialic acid. The endocervix gradually secretes more H20 and MG, decreasing the concentration of transudated serum proteins in the mucus and increasing the amount of MG relative to proteins. The peak of the process is achieved during the midcycle. Although the high rate of MG secretion declines rapidly after the ovulation period, the MG concentration increases because of the decrease in H20 secretion. Both a higher concentration of MG and a high protein to MG ratio may account for the increase in viscosity of the mucus after ovulation. Mixing of MG and protein fractions into reconstituted mucus may be useful in analyzing the contribution of each of them, separately or in combination, to the physicochemical properties of cervical mucus.

Age-dependent decrease in embryo implantation rate after in vitro fertilization.

OBJECTIVE: To investigate the relation between the implantation rate per embryo after replacement in IVF-ET in relation to female age. DESIGN: Retrospective study using linear and biphasic models in a multivariate analysis. SETTING: Academic tertiary care institution. INTERVENTION(S): In vitro fertilization-ET and determination of gestational sacs at 6 to 7 weeks of pregnancy buy ultrasound. MAIN OUTCOME MEASURE(S): Implantation rate as defined by the number of gestational sacs per embryo replaced. RESULT(S): Woman's age and embryo morphology were strongly related to the implantation rate, indication for IVF-ET and cycle rank number also were related significantly but less strongly. A linear model was built describing the decrease in implantation rate with age, resulting in a decrease of approximately 7%. A biphasic model was tested also and performed significantly better, resulting in a yearly decrease of > 20% after 37 years of age. CONCLUSION(S): The most important independent factors related to the ability of embryos to implant are female age and embryo morphology. The best way to describe the relation with female age is biphasic model with a discontinuity at approximately 37 years of age.

Is there a carryover effect of mild ovarian hyperstimulation with gonadotropins on the subsequent cycle?

OBJECTIVE: To investigate the effect of mild ovarian hyperstimulation on hormonal and sonographic variables of the subsequent natural cycle. DESIGN: Prospective study of three consecutive cycles. SETTING: University Hospital, Department of Reproductive Medicine, Division of Obstetrics and Gynecology. PATIENTS: Twelve couples with subnormal semen as the only identifiable cause of subfertility. INTERVENTIONS: Subjects were offered IUI for three cycles. In the second cycle, mild ovarian hyperstimulation with 75 IU IM hMG was applied daily and ovulation was induced with 5,000 IU hCG. In the first and third both natural cycles, serum samples were obtained for hormone measurements and ultrasound (US) scanning of the ovaries was performed. MAIN OUTCOME MEASURE: To determine whether there was a carryover effect of mild ovarian hyperstimulation as applied in the second cycle, hormone levels and US scans of cycle 3 were compared with those of cycle 1. RESULTS: None of the variables of cycle 3 were significantly different from those of cycle 1. CONCLUSION: Because hormonal and sonographic variables in the subsequent natural cycle remain unchanged, a carryover effect of mild ovarian hyperstimulation with gonadotropins seems unlikely.

The pattern of the luteinizing hormone surge in spontaneous cycles is related to the probability of conception.

OBJECTIVE: To determine whether the pattern of the LH surge in a treatment cycle with artificial insemination with the husband's semen (AIH) because of cervical factor infertility is associated with the probability of conception. DESIGN: Retrospective study. SETTING: University Hospital, Department of Obstetrics and Gynecology. PATIENTS: Couples with cervical factor infertility as the main cause of subfertility. INTERVENTIONS: Luteinizing hormone monitored AIH. MAIN OUTCOME MEASURE: Whether or not a pregnancy occurred after AIH. RESULTS: There were 53 pregnancies in 382 IUI cycles (pregnancy rate [PR] per cycle: 13.9%). The PR was significantly higher in cycles with an LH surge of 2 days compared with cycles with a surge of 1 day. The probability of conception also seemed to be related to the height of the LH surge. CONCLUSION: The pattern of the LH surge in patients with cervical factor infertility is related to the outcome of a treatment with AIH.

Occupationally related exposures and reduced semen quality: a case-control study.

OBJECTIVE: To determine whether there is an association between abnormal semen parameters and occupational exposures to organic solvents, metals, and pesticides. DESIGN: Case-control study using three case groups based on different cutoff values for semen parameters and one standard reference group. SETTING: University Hospital Utrecht and University Hospital Rotterdam, the Netherlands. PATIENT(S): Male partners of couples having their first consultation at the two infertility clinics (n = 899). INTERVENTION(S): Men provided at least one semen sample. Occupational exposure was assessed with use of job-specific questionnaires, a job exposure matrix, and measurements of metals and metabolites of solvents in urine. MAIN OUTCOME MEASURE(S): Standard clinical semen analyses were used to define case groups and controls. RESULT(S): An association between aromatic solvents and reduced semen quality was demonstrated, irrespective of the exposure assessment method used. The associations were stronger if the case definition was based on stricter cutoff values for semen parameters. Risk estimates were higher if the analysis was restricted to primary infertile men. Exposure to other pollutants at the workplace was not associated with impaired semen quality. CONCLUSION(S): The findings indicated an association between aromatic solvent exposure and impaired semen parameters.

General ageing and ovarian ageing.

The age related decrease in female fertility is associated with a decrease in follicle numbers and oocyte quality. Meiotic division errors, mitochondrial DNA mutations and ageing itself have been suggested to play a part in the age associated reduction in oocyte quality. During the past decades several hypothesis have been proposed, trying to explain the underlying mechanisms. However, none of them is yet conclusive. This review will consider the main hypotheses regarding the age related reduction in oocyte quality. This will be reviewed together with recent results of studies analysing a possible relationship between ageing and ovarian ageing. On the basis of our own results and those presented in the literature, it is concluded that ovarian ageing may only be related to specific aspects of general ageing.

Synthesis of a mucous glycoprotein in the human uterus.

Scrapings of endometrium and uterine contents of 10 women were analysed. In the uterine lumina of two women that used synthetic progestagens, a considerable amount of mucus was present. We fractionated the mucus by CsCl density equilibrium centrifugation into glycoprotein and protein fractions. With sugar and amino acid analysis the glycoprotein could be classified as a typical epithelial glycoprotein, resembling the cervical glycoprotein. It contains neuraminic acid (6.2%) and sulfate (8.4%). From the uteri of the other 8 women, who did not use hormones, a small amount of a similar glycoprotein could be isolated.

[Exposure to pseudo-estrogens and the quality of sperm]. / Blootstelling aan pseudo-oestrogenen en spermakwaliteit.

Some synthetic chemicals and natural compounds occurring in vegetables or animal food products mimic endogenous hormones, especially oestrogens, or may have a general action of disturbing hormonal status. It is assumed that intrauterine exposure to these compounds may have an adverse effect on development, differentiation and function of the genital organs of the male foetus. In a worldwide discussion a supposed drop in human sperm quality is related to foetal exposure to chemicals with oestrogen activity. Experimental animal evidence suggests that foetal exposure to compounds with oestrogenic activity may influence reproductive capabilities. In addition chemicals such as diethylstilbestrol (DES) in humans and dichlorodiphenyltrichloroethane (DDT) in wildlife influence the reproductive system. There is no conclusive evidence of decreasing semen quality in general.

[Male subfertility, modern reproduction techniques and transmission of genetic abnormalities]. / Mannelijke subfertiliteit, moderne voortplantingstechnieken en het doorgeven van genetische afwijkingen.

Somatic cells of males with azoospermia or oligozoospermia (sperm density < 20 million sperm cells/ml) were found to contain increased percentages of chromosomal abnormalities. Subfertile males with a normal somatic karyogram were found to have increased rates of aneuploidy in sperm. This creates risks for the offspring after fertilization with intracytoplasmatic sperm injection (ICSI). Certain gene mutations on the Y chromosome cause severe oligo- or azoospermia and will, in case of successful reproduction with ICSI, be transmitted to male offspring in 100% of the cases. The same holds true, irrespective of sex, of mutations responsible for cystic fibrosis. In non-random groups of ICSI pregnancies, higher proportions of de novo sex-chromosomal abnormalities have been found than expected. In addition, there are increased proportions of paternally inherited structural autosomal anomalies. Extrapolation of the findings is not yet possible, however.

A new Dutch Law regulating provision of identifying information of donors to offspring: background, content and impact.

In 2004 a law was introduced in The Netherlands, which gives offspring conceived by semen or oocyte donation the right to know the identity of the donor. The law also regulates the provision of other information concerning the donor to the offspring, their parents or their general practitioner. With the introduction of this law, a choice has been made in which the wish of offspring prevails above others involved. Donors can no longer claim absolute anonymity; they are anonymous at the time of donation, but if a child aged > or =16 years requests information the donor may now be traced. During 15 years of debate on the abolition of donor anonymity the number of donors decreased by >70% and the number of semen banks by 50%. We describe the debate which led to the law, the characteristics of the law itself and note some of the probable and possible consequences for donor offspring, parents, donors and semen banks.

Secretion of newly synthesized proteins by isolated liver cells.

Suspensions of isolated liver cells were incubated with [3H]leucine as a precursor. The appearance of radioactive albumin and alpha 1-acid glycoprotein in the incubation medium was determined. After about 20 min both albumin and alpha 1-acid glycoprotein were secreted in a linear way. When fucose and galactose were used as radioactive precursors, time lags of about 10 min could be observed.

The presence of zonae pellucidae influences fusion rates between spermatozoa and zona free hamster oocytes.

Human zonae pellucidae were added to suspensions of capacitating spermatozoa. The zonae were prepared from oocytes that remained unfertilized in our in-vitro fertilization (IVF) programme. After capacitation, zona free hamster oocytes were added and the penetration rate of the hamster oocytes was determined. Controls without the addition of zonae were run in parallel. A distinct enhancement of the penetration rate was found when zonae were present during capacitation, using sperm of fertile donors. Sperm of several infertile men did not respond to the presence of zonae with higher penetration rates. It was concluded that the zona pellucida is involved in the induction of the acrosome-reaction of human spermatozoa. In addition the incubation system with zonae as described might be useful for the identification of infertile semen.

Fertilization of human oocytes by spermatozoa from an artificial spermatocele.

Spermatozoa from a patient with an artificial spermatocele (Dardik's prosthesis) implanted onto the vas deferens were found to have high levels of IgG/IgA antibodies absorbed on their surfaces (MAR-test). Pre-treatment of such sperm with Percoll/BMW (d = 1.05) apparently reduced their MAR positivity and improved their ability to penetrate into ZP-free hamster oocytes or into the oocytes of the wife, respectively.