Cyclic changes in the physical and chemical properties of cervical mucus

Cervical mucus at midcycle is increased in amount, acellularity, water content, and fluidity. Furthermore, cervical mucus at this time is well supplied with carbohydrate and presumably amino acids. From a teleologic standpoint, we may conclude that because of these characteristics the sperm, on deposition in the vagina, find an environment propitious for their nutrition and migration through the cervical canal.     

Presence of prolactin in human cervical mucus.

The presence of prolactin in human cervical mucus was demonstrated by radioimmunoassay. The levels of prolactin in cervical mucus were significantly higher (260 ng/ml +/- 47.5 SE) than those in sera of normally menstruating women (30.28 ng/ml +/- 2.0 SE).     

Bovine cervical mucus as a substitute of human cervical mucus

The sperm penetration test (SPT) in cervical mucus (CM) is an important test in screening for sperm-CM incompatibility. For a routine SPT, a sufficient amount of preovulatory CM is necessary, but the amount of human CM is often inadequate. We examined estrous bovine CM as a substitute for human CM in the SPT. Preovulatory human CM and estrous bovine CM were collected and stored frozen at -20 degrees C until use. After being thawed at room temperature, the two CM samples were compared as to their pH, spinnbarkeit and ferning patterns, and it was found that they are quite similar. In Kremer's method of SPT, sperm penetration distance, density and motility were similar in human and bovine CM for 12 hours, but thereafter sperm motility became much lower in bovine CM than in human CM. The results of SPT with spermatozoa from patients with oligozoospermia were quite similar in both CMs. When spermatozoa pretreated with antisperm antibody were used for SPT, sperm penetration was completely blocked in human CM, but no inhibition was seen in bovine CM. From these results, we conclude that bovine CM can be substituted for human CM for some, but not all, purposes.     

Structural aspects of human cervical mucus.

Two types of fibrous structures can be demonstrated in midcycle cervical mucus: (1) long, thick fibers that vary in diameter from 0.5 to 5 mum and run parallel to each other, and (2) microfibrils that vary in diameter from 500 to 1,500 A and form bundles or networks. The spaces in such networks usually measure from 800 to 4,0000 A. The fibers are made up of the microfibrils and most likely represent the micelles that give spermatozoa their directional transport through the cervix.     

Oral contraceptives and human cervical mucus lipids.

Oral contraceptives containing estrogenic and progestational components caused a consistent increase in human cervical mucus lipids during the menstrual cycle. Cyclic variations in cervical mucus lipids occur during the normal cycle. Phospholipids, free cholesterol, and triglycerides in cervical mucus increase with the use or oral contraceptives.     

The canalization of cervical mucus in the human fertility.

Canalization of cervical mucus from 31 patients at the obstetric/gynecologic clinic at the Universita Cattolica del S. Cuore in Rome, Italy has studied to determine the biochemical basis of canalization and its dependence on estrogen, to study the action on the canalization of hormones used to induce ovulation, and to correlate fern pattern and canalization. Cervical mucus was collected daily and applied to a glass slide, covered with an object cover, and allowed to dry. The typical arrangement of the dendritic crystals and the presence of channels among them were confirmed. Depending on the phase of the ovulatory cycle, the crystals differed in direction and in number. The number of channels consistently increased as estradiol levels increased during the proliferative phase. This happened in both natural and induced ovulatory cycles. The cervical mucus of patients with primary amenorrhea canalized when treated with estrogens. The channels ran parallel to each other. Yet, during the secretory phase, the number of channels fell rapidly and the channels were lined up in a crisscross fashion. This suggested that sperm penetration is dependent on the orientation of mucus crystals. Indeed in vitro studies showed that spermatozoa enter the periovulatory mucus in tightly packed files as if the mucus allowed only passage in this linear formation. The biophysical characteristics of canalization paralleled those of ferning. Moreover, like ferning, the presence of essential salts and proteins induced canalization. It is concluded that canalization can be used to accurately measure estradiol levels and thus to detect ovulation.     

Canalization of human cervical mucus

Cervical mucus forms channels when dried under a coverslip. The aim of the present work was: 1) to prove mucus canalization both in spontaneous ovulatory cycles and during ovulation induction with gonadotropins; 2) to prove the estrogen dependence of this phenomenon; 3) to check the importance of the proteidic and electrolytic concentration on chaneling; and 4) to use this phenomenon clinically, shortening the time in which it occurs. The number and arrangement of channels vary during the cycle. The phenomenon is estrogen-dependent. The comparison between estradiol values and the number of channels during spontaneous ovulatory cycles and treatment with gonadotropins showed a linear relationship. Treatment with estradiol 17 beta-valerate and ethinyl estradiol induced channel formation in women with primary amenorrhea. Canalization and ferning disappeared after dialysis or treatment with proteolytic enzymes. It follows that the two phenomena have similar characteristics. Canalization increases daily, as does estradiol, whereas ferning maintains the same grade for a longer period, and when a grade of + + + is reached, it provides no further indications. With the use of a thermostat, canalization occurred in only a few hours. Chaneling, a more precise index, could therefore substitute for ferning, particularly when monitoring the induction of ovulation.     

Cyclic changes in the concentration of prostaglandin F2alpha in human uterine flushings

Prostaglandin F2alpha (PGF2alpha) was measured by radioimmunoassay in uterine flushings obtained from 41 women at various stages of the menstrual cycle. The concentration of PGF2alpha changed significantly during the cycle, with highest values in the mid secretory phase of the cycle (mean 9.1 ng/ml of uterine flushing, range 3.9 to 16.0 ng/ml, n = 9). The still unresolved role of intrauterine PGF2alpha is discussed in relation to luteolysis, myometrial contractility and implantation.     

Crossed immunoelectrophoresis of sperm antibodies in human serum and cervical mucus.

Sperm agglutinating antibodies are purified from sera and cervical mucus of women with unexplained causes of infertility which were positive in the FD-test. Fractionation was performed by affinity-chromatography in a batch device and the sperm agglutinating activity controlled by the Franklin and Dukes test. This sperm antibody fraction was determined via crossed immunoelectrophoresis by migration into an anti-human serum containing gel. In all cases only one big peak resulted. The negative control serum and mucus samples demonstrated no precipitation peaks. By absorption studies it was shown that the sperm agglutinating antibodies in sera were IgM and in cervical mucus IgA. The concentration of IgA and IgM was determined by comparison with standard human IgA and IgM. Thus only one serum- and one cervical mucus antibody seems to be responsible for agglutination. The number of experiments, however, is still too small for general conclusions. This method is easily and quickly performed and can therefore be used as a routine method for the determination of sperm agglutinating antibodies. Its application for sperm-immobilizing or cytotoxic activity remains to be tested.