China
Africa
Explore chapters and articles related to this topic
Prelabor Rupture Of Membranes At Or Near Term
Published in Vincenzo Berghella, Obstetric Evidence Based Guidelines, 2022
A third helpful test is called “ferning.” A swab of vaginal fluid from the posterior fornix is placed on a slide and allowed to air dry. Arborization (ferning) under microscopic visualization suggests rupture of membranes. Cervical mucus can cause a false-positive result. Ferning has a sensitivity of 90.8% (62.0%–98.5%) and a specificity of 95.3% (88.2%–100%) [2].
Motility Parameters and Fertility
Published in Claude Gagnon, Controls of Sperm Motility, 2020
Cervical mucus represents one of the first and most profound barriers that a spermatozoon must transcend on its route towards the human ovum. Analysis of the relationship between the movement characteristics of human spermatozoa and their capacity for cervical mucus penetration has been facilitated by the development of in vitro tests to quantify this aspect of human sperm function.2 In general, these tests involve the use of capillary tubes loaded with cervical mucus, one end of which is inserted into a liquified semen sample. After a defined period of incubation at 37°C, the number of spermatozoa penetrating the mucus is assessed. There is, as yet, no universally agreed means of calculating the outcome of such cervical mucus penetration assays, although a number of authors3,4 have used the formula introduced by Katz et al.2 This calculation depends upon a knowledge of the concentration of motile spermatozoa in semen in units of 106/ml (Cs), the concentration of spermatozoa in the mucus as the 106/ml (Cm), the length of the capillary tube in micrometers (1), the time of the incubation in seconds (t), and the mean path velocity of the cells (Vs). Insertion of these values into the following equation:
Regulation of Reproduction by Dopamine
Published in Nira Ben-Jonathan, Dopamine, 2020
The cervix in nonpregnant women is rather narrow, allowing passage of sperm in and menstruation out. Cervical mucus undergoes cyclic changes in composition and volume. During the follicular phase, estrogen increases the quantity, alkalinity, viscosity, and elasticity of the cervical mucus. Mucosal elasticity is greatest at ovulation, providing a suitable environment for sperm survival and transport. With the rising progesterone levels at the luteal phase, the quantity and elasticity of the mucus decline and it becomes thicker. At this time and throughout pregnancy, the cervical mucus provides protection against infection.
Recent advances in the mucus-interacting approach for vaginal drug delivery: from mucoadhesive to mucus-penetrating nanoparticles
Published in Expert Opinion on Drug Delivery, 2019
Silvia Rossi, Barbara Vigani, Giuseppina Sandri, Maria Cristina Bonferoni, Carla M. Caramella, Franca Ferrari
Nowadays many papers dealing with mucoadhesive nanosystems for vaginal drug delivery have been published. The vaginal mucosa is characterized by a non-keratinized epithelium covered by a discontinuous fluid composed by cervical mucus, vaginal transudates, and secretions from vestibular glands, having lubricant and protective actions [2]. Cervical mucus production rate is affected by several factors, including the number of mucus-secretory units in the cervical canal, the percentage of mucus-secreting cells per unit and the cell secretory activity in response to circulating hormones [8,9]. In healthy women in fertile age, vaginal fluid/mucus is characterized by a pH value of 4–5 and its main components are water (about 95%) and negatively charged glycoproteins or mucins of cervical origin (1–2%) [2,10].
Delivery of progestins via the subdermal versus the intrauterine route: comparison of the pharmacology and clinical outcomes
Published in Expert Opinion on Drug Delivery, 2018
Norman D. Goldstuck, Hung P. Le
All three LNG-IUSs and both the LNG and ENG implant have the potential to influence reproductive physiological function both centrally in the hypothalamus and peripherally in the genital tract itself. The principle pharmacological actions of these delivery systems include: i) blocking the LH surge and inhibiting ovulationii) alteration of the nature of cervical mucus (decreased Insler score [24])iii) alteration of endometrial structure and functioniv) possible alteration of tubal motility and function
Prediction of male infertility by the World Health Organization laboratory manual for assessment of semen analysis: A systematic review
Published in Arab Journal of Urology, 2018
Amir S. Patel, Joon Yau Leong, Ranjith Ramasamy
Another absolute predictor for male infertility is the detection of globozoospermia on semen analysis. It is a rare but severe form of teratozoospermia, characterised by the presence of round-headed spermatozoa lacking an acrosome [42]. The acrosome contains the digestive enzyme, acrosin, which is essential for binding and penetration of the zona pellucida of the ovum. It also facilitates cervical mucus penetration and intrauterine sperm migration. It also participates in chromatin decondensation in the oocyte [43]. Considering these factors, we can understand how globozoospermic cells have difficulties adhering and fusing with the oocyte membrane, ultimately causing infertility. A microscopic image of globozoospermic spermatozoa can be seen in Fig. 2 [44].