Very often we found some questions like What is fertilization in embryology, How long does it take for a sperm to fertilize an egg, How does fertilization take place, How does fertilization occur etc. As the reply to said questions, this content will be exact solution. Steps of Fertilization in Humans have discussed briefly through this post. Human fertilization uses to occur in basically 4 steps of fertilization.
During the cycle, about 14 days after each normal menstrual period one ovum is usually released from one of the ovaries which are called ovulation. The ovum is swept into the funnel-shaped end of one of the fallopian tubes. If a sperm penetrates into the ovum called fertilization results. Fertilized zygote which to see the tiny hairlike propel through the tube toward the uterus and it takes to enter the uterus about 3 to 5 days. The cells continue to divide in the uterus and turn into the hollow ball that called a blastocyst. If fertilization does not occur the ovum degenerates and moves down the fallopian tube to the uterus and passes the next menstrual period.
Often we found more than one fetus usually twins when more than one ovum has released and fertilized. Each fertilized ovum is different because of the genetic material of each ovum and sperm is slightly different. The resulting twins are growing up in zygote thus brotherly twins.
Ovum to Embryo & Development
One ovum is released from ovary only once in a month and this incident usually occurs about 14 days after each normal menstrual period. During the ovum release period, if one complete sexual intercourse one sperm fertilizes the ovum by moving from the vagina through the uterus to the fallopian tubes. The fertilized zygote divides repeatedly and firstly it becomes a solid ball of cells and next to a hollow ball of cells called a blastocyst as it moves down the fallopian tube to the uterus. The blastocyst sets up inside in the wall of the uterus and develops into an embryo surrounded by fluid-filled membranes and also attached to a placenta.
Upliftment of the Blastocyst
The blastocyst attaches to the lining of near the top of the matrix from 5 to 8 days after fertilization is called implantation that fully completed by day 9 or 10. The wall of a blastocyst is three to four cells thick but in one area one cell thick. In the thickened area, the inner cell develops into the embryo and outer develop into the placenta burrow into the wall of the Venter. Some of the cells develop into an outer layer of chorion and other develops into an inner layer of amnion that forms the amniotic sac by about day 10 to 12 is considered a fetus which fills with a clear liquid.
Advancement of the Fetus
About day 16 the heart and major blood vessels begin to develop and about 20 the heart begins to pump fluid through blood vessels and blood vessel continue to develop in the fetus and placenta. The most internal organ and external body structures are formed during this stage. Most of the organs use to form in about 3 weeks that is clinically equals 5 weeks because of doctors declared the pregnancy date from the first day of the woman’s last menstrual period but we know fertilization usually occurs about 14 days after completing the last menstrual period. The fetus becomes enlarged and formed into human shape first at this time and shortly thereafter the brain and spinal cord begin to develop. Almost all organs are completely formed by about 10 weeks after fertilization but the brain and spinal cord continue to form and develop throughout pregnancy. At this stage, the pregnant should not be taken any vaccinations or drugs unless they are considered essential to a specialist because of in this period the fetus is most vulnerable to the effects of drugs, radiation and viruses.