How is an egg fertilized by a spermatozoon? How long does sperm survive and how does the embryo enter the uterus?
Spermatozoa are "sucked up"
- It was once believed that the mobility of spermatozoa it was used to move from the bottom of the cavity of the vagina to the trunk. Today, we know that this is not the case: in women, there is, at about the time of ovulation, a kind of aspiration mechanism during which the cervix transports everything at the bottom of the vaginal cavity upwards.
- This suction mechanism is supported by the male sperm prostaglandin. Note that the female orgasm favors it by the contractions of the uterus.
- So that the sperm "target the good horn"it is largely open thanks to a greater production of estrogen on the side where the follicle is, clusters of cells surrounding the ovum. The combined action of strengthening irrigation and estrogen causes the proboscis to open widely. On the other side, there is no follicle, so irrigation is less and the trunk is "physiologically" closed.
- Spermatozoa reach maximum mobility when body temperature is 37 ° C. After ovulation, the body temperature of the woman is even higher, under the influence of the corpus luteum. This gland, formed after the bursting of the follicle, produces estrogen and progesterone in order to prepare the uterine lining for implantation of the egg.