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Physiological System Modeling
Published in Sujoy K. Guba, Bioengineering in Reproductive Medicine, 2020
By removing the vas deferens from adult male rhesus monkeys weighing over 8 kg and performing serial frozen sections the radius variations of the vas deferens along its length is seen to be as shown in Figure 1.5. Ejaculated semen comprises of the spermatic fluid coming from the vas deferens and the secretions of the seminal vesicles, which form the bulk of the semen. Assuming that the entire seminal content of spermatic fluid passes along the vas deferens during the ejaculatory phase, the average flow rate of spermatic fluid in the vas deferens works out to be 0.009 ml s_1 in the monkey. The flow velocities are low and Reynold’s number for the experimentally obtained spermatic fluid viscosity of 0.004 N s/m is 17.6. For such a low Reynold’s number Poisseulle type flow may be assumed and the pressure differential between the beginning and the end of the vas deferens for the notations given in Figure 1.5 is
Perception, Planning, and Scoping, Problem Formulation, and Hazard Identification
Published in Ted W. Simon, Environmental Risk Assessment, 2019
Considerable variation in semen quality parameters exists in humans. This variation is due to both between- and within-person variability. The 2010 World Health Organization (WHO) Laboratory Manual for the Examination and Processing of Human Semen, 5th edition, flatly states that it is impossible to characterize semen quality from evaluation of a single sample.212 Length of abstinence is a major determinant of this variation.213 A commonly measured semen quality parameter is sperm concentration, the number of spermatozoa, usually in millions, in a milliliter of semen. Sperm concentration is related to time to pregnancy and is a predictor of conception.214 Sperm concentration is measured by counting individual sperm using a haemocytometer grid.215
Semen Analysis
Published in Botros Rizk, Ashok Agarwal, Edmund S. Sabanegh, Male Infertility in Reproductive Medicine, 2019
Meaghanne K. Caraballo, Alyssa M. Giroski, Rakesh Sharma, Ashok Agarwal
After liquefaction, semen samples undergo a macroscopic analysis. Normal semen sample is opaque in appearance and homogenous. If the specimen has a clear appearance, the patient’s sperm concentration may be too low or possibly even azoospermic. On the other hand, if it has a reddish-brown appearance, then there may be red blood cells present. Hematospermia (i.e., appearance of blood in the semen) can be attributed to a variety of factors such as infection or inflammation in any area of the male reproductive system, excessive masturbation, obstruction, tumors, or polyps. Certain pharmaceutical drugs and medical conditions (e.g., jaundice or prostate infection) can cause an abnormal appearance of the semen. Urine contamination can alter the appearance of semen to a yellowish color.
Repair mechanism of Wuwei Fuzheng Yijing formula in di-2-ethylhexyl phthalate-induced sperm DNA fragmentation in mice
Published in Pharmaceutical Biology, 2022
Chenming Zhang, Shiqi Wang, Zulong Wang, Qi Zhang, Rubing Chen, Hao Zhang, Zhong Hua, Sicheng Ma
It is estimated that approximately 15% of couples of childbearing ages suffer from infertility worldwide, and the incidence is increasing year by year. Approximately, half of infertility cases are attributed to male factors (Inhorn and Patrizio 2015). The semen quality of men has decreased gradually. In the 50 years from 1940 to 1990, the sperm density decreased from 113 × 106/mL to 66 × 106/mL. As seen from the different editions of the World Health Organization (WHO) Laboratory Manual for the Examination and Processing of Human Semen (hereafter referred to as the Manual), semen quality is progressively worsening (WHO 1980). The first edition of the Manual, published in 1980, states that the normal semen density is 60 × 106/mL, but it has been changed to 15 × 106/mL in the fifth edition of the Manual published in 2010 (WHO 2010). In just 70 years, the sperm density has dropped to about a tenth of what it used to be. More worryingly, neither the exact cause of the sperm quality decline nor an effective treatment for it has been found.
Sperm DNA fragmentation on the day of fertilisation is not associated with assisted reproductive technique outcome independently of gamete quality
Published in Human Fertility, 2022
Jorge Ten, Jaime Guerrero, Ángel Linares, Adoración Rodríguez-Arnedo, Ruth Morales, Belén Lledó, Joaquín Llácer, Rafael Bernabeu
Data from 140 couples were included in the analysis. It was not possible to assess the DFI using the TUNEL technique in seven couples, two cycles had PGD and one was a donation cycle included by mistake, so these data were not analysed. Mean paternal age was 39.2 ± 6.3. In contrast to the two previous patient groups, the quality of the semen samples was not taken into account as an inclusion criteria. Semen samples had an average concentration of 37.1 ± 21.2 million spermatozoa/mL and a total of 22.6 ± 13.4 million/mL progressive motile sperm. The median DFI value of the subjects of the study was 5.8%, with a minimum of 0 and a maximum of 63.8%. Mean maternal age was 37.4 ± 4.7, the average number of oocytes obtained was 4.4 ± 3.1, the fertilisation rate was 66.5% and the mean number of embryos transferred was 1.8 ± 1.2 on day 3 of embryo development. The global clinical pregnancy rate was 28.3%, with a first trimester miscarriage of 2.9%. The results are shown in Table 6.
Lactic acid, citric acid, and potassium bitartrate non-hormonal prescription vaginal pH modulator (VPM) gel for the prevention of pregnancy
Published in Expert Review of Clinical Pharmacology, 2022
In an in vitro study utilizing vaginal products added to fresh human semen, the VPM vaginal modulator gel demonstrated dose-dependent pH decreases in semen as well as sperm immobilization activity [35]. In that study, the average pH of semen was 7.64. VPM produced a greater decrease in pH compared to Aci-Jel, which is a vaginal gel containing 0.94% glacial acetic acid marketed to maintain the normal acidity of the vagina (but without an indication for use as a contraceptive agent) [38]. The pH of VPM gel alone was 3.45 compared to 4.05 for Aci-Jel alone. When one part gel was mixed with two parts semen, the VPM:semen mixture had a pH of 4.45 in comparison to 5.79 with Aci-Jel. Additionally, for a 1:1 or 1:2 mixture of VPM and semen, 100% sperm immobilization was achieved. When diluted to 1:4 gel to semen, there was only 67% immobilization of sperm and the pH of the mixture was 5.54, demonstrating the importance of acidic pH for immobilization of sperm for this product.