Getting pregnant is not an easy task, but understanding the essential physiology of the process is the best place to start. In this chapter I will describe the arduous journey that sperm must make through the female genitals to reach the egg, as well as the simultaneous adventure of the egg during which it matures to become genetically ready for fertilization, erupts from the ovary, and gets grabbed by the fallopian tube, fertilized, and then hustled along into the womb at exactly the right moment to implant. Failure of the sperm or egg to make an important connection anywhere along this complicated itinerary will prevent pregnancy from occurring. The vagina is an elastic canal, about four to five inches long. At the end of this canal, in the deepest recess of the vagina, is a structure called the cervix, which is the entrance to the womb, or uterus. The uterus is a hard, muscular, pear-shaped structure with a narrow, triangular cavity inside, so small that it would barely hold a teaspoonful of fluid. Yet this is where the fertilized egg must implant itself and grow during the next nine months into a full-size baby.
Cowgirl and reverse cowgirl
In vaginal depositors, the cervix has the unique function of preventing the influx of pathogens from the vagina to the uterus while serving to regulate sperm passage. Of the millions to billions species-dependent of spermatozoa deposited in the female reproductive tract FRT , less than spermatozoa arrive at the site of fertilisation and the cervix plays a critical role in the selection of the successful few see review by Sakkas et al. Despite intensive research efforts, the sheep is the only large domestic animal species in which it remains currently impossible to traverse the cervix during artificial insemination AI and therefore the furthest semen can usually be deposited is at the external cervical os opening. Laparoscopic AI is labour intensive, requires specialist veterinary expertise and is not considered welfare friendly. Therefore, for the extensive uptake of sheep AI, which provides widespread access to elite genetics, an improved approach for routine cervical deposition of semen must be devised. However, the understanding of the factors regulating sperm selection in the cervix remain elusive, and this precludes the development of sheep AI.
Suarez, A. At coitus, human sperm are deposited into the anterior vagina, where, to avoid vaginal acid and immune responses, they quickly contact cervical mucus and enter the cervix. Cervical mucus filters out sperm with poor morphology and motility and as such only a minority of ejaculated sperm actually enter the cervix. In the uterus, muscular contractions may enhance passage of sperm through the uterine cavity.
We all know you can achieve an orgasm from clitoral or vaginal simulation. But did you know that the cervix is also a pleasure zone? We rounded up the most pressing concerns about cervix penetration so you can get down to business worry-free. The bare-bones definition of penetration is this: any object that makes its way through or into something.