Pregnancy

Giving Birth to a baby

And exercises to prepare for child birth as well as for regaining their figure once the child is born.

We hope that these sections will be helpful but it is advisable to contact your doctor before trying any of this.

PREGNANCY

Biologically speaking, the purpose of sexual intercourse is to create a new human life. However, human sexual activity also express and emphasizes the love that exists between a man and a woman.

At the climax of any one act of intercourse, hundreds of millions of sperms are introduced into the vagina by the man. They pass through the mucus in the lower end the womb and along the Fallopian tubes. Somewhere in one tube they may encounter an egg. If a sperm and an egg combine, fertilization takes place. Only one sperm penetrates the egg, but the millions of others in any one ejaculation are not wasted, since their presence is necessary to overcome chemical barriers at the entrance to the womb.

Theoretically, ovulation and so fertilization can occur at any day of the menstrual cycle. In practice, however, it usually occurs only during the middle part of the menstrual cycle. For example, a woman with a 28 day menstrual cycle may conceive between the thirteenth and fifteenth days. There is also possibility that conception might take place between the sixteenth and twentieth days, it is less likely beyond that day, or in the early part of the next cycle.

Once the egg has been fertilized, its outer membrane changes so that no other sperm can enter. Within day or two, the fertilized egg starts moving towards the womb. During the journey it divides repeatedly to form a ball of cells, known as a blastocyst. When the blastocyst reaches the womb, it becomes surrounded by cells from the womb lining - the process of implantation.

Very occasionally, the fertilized egg lodges in one of the fallopian tubes or in the abdominal cavity and grows there. This is called an ectopic pregnancy, and it causes symptoms such as abdominal pain and bleeding from the vagina within a few weeks. Eventually the embryo has to be removed by surgery.Within a day or so of implantation, the blastocyst in the womb divides rapidly and starts to increase in size. Soon its outer layer begin to secrete hormones which maintain the corpus luteum, left in the ovary after the release of the egg. In the normal menstrual cycle, the life of the corpus luteum is about ten days. But in the presence of these new hormones it remains throughout pregnancy. The rorpus luteum has a vital job to do during the early stages of pregnancy: it secretes oestrogen ad progesterone, two hormones which stop menstruation and ovulation. This maintains the womb lining, ready to receive the fertilized egg, and ensures that once a woman is pregnant, she cannot conceive again during her pregnancy. It also keeps the womb in the right state to nurture the growing foetus. During the 4th month, the abdomen enlarges. The foetus is about 8 inches long, and the mother feels its movements. By eight months, the breasts are enlarged, and the woman leans back to counterbalance her extra weight. In the 9th month, the swelling moves downwards.

If at any stage before the third month the corpus luteum is removed, the pregnancy ends in abortion. After third month, the placenta takes over the secretion of the hormones oestrogen and progesterone. These two produce many of the changes in a woman's body during pregnancy, such as the development of mammary glands in the breasts.

The average length of pregnancy is 273 days, calculated from the day on which conception took place. Usually, however, pregnancy is dated from the first day of the last normal menstrual period. To calculate the expected date of delivery, 280 days are added to this date or roughly nine calendar months plus seven days. An additional check is that 'quickening' the first movements of the foetus felt by the mother, usually occurs about the eighteenth week of pregnancy. The earliest symptom of pregnancy is the ending of menstruation, and in a woman of child bearing age who is sexually active the most common cause of a missed period is pregnancy. (Menstruation may also cease during times of mental stress, or a single period may be skipped at a time when a young woman is anxious or feeling guilty about sexual experimentation.

Shortly after the first missed period other symptoms begin. The breasts increase in size, become slightly tender, and later darken around the nipples. Morning sickness may start about he sixth week, and often persists for two or three months, the woman may find she wants to pass urine more frequently, because her bladder is compressed by the enlarging womb. A doctor may able to detect in increase in the size of the womb and by about 12 weeks he can see changes in the color of the vaginal walls ad the cervix.

Much the most reliable confirmation of pregnancy is a chemical test on the woman's urine. There are a number of such tests, which work by detecting hormones secreted by the developing foetus and its placenta.

There are 2 more aspects of pregnancy which will be discussed in detail in the following sectionsA Woman's body has nine months to prepare of labour. During these months, hormones in the bloodstream cause softening and stretching of the muscles and ligaments of the birth canal, so that the stretching required during labour is not a sudden process. Biologists still do not know exactly how labour starts. In some way, the maturity of the baby triggers off the process, so that premature childbirth is a comparatively rare occurrence.

Labour is divided into three stages. In the first labour pains-which are muscular contractions of the womb gradually start at intervals of about 20 minutes. These pains become stronger and more frequent, until they occur every three stretch open the lower end of the womb. The cervix, and the baby is pushed down, head first in most cases, into the pelvis. The first stage ends when the cervix is fully open, ready for the baby to be born.

During the second stage, the baby is pushed from the womb and out of the birth canal, the muscular surrounding the vagina are soft and stretch out of the way, and there is no difficulty unless the bones of the pelvis obstruct the passage of the baby. Assessing the diameter of the bony exit of the pelvis is one of the major duties of the doctor supervising the pregnancy; if it is likely to be to narrow, he will probably make arrangements to deliver the baby by caesarian section, in which the baby is born through a surgical incision in the mother's abdomen.

The third stage of labour is the expulsion of the placenta, the afterbirth, once the baby has been born.

The first warning of labour is usually already the onset of labour pains, I a woman who has already had a baby, 'lightening' may occur a few days before labour. This is the increase in comfort left by the mother when the baby's head sinks firmly into the pelvis. It usually occurs these or four weeks before labour in a first pregnancy, and so it is no help in timing childbirth.

1.) By the ninth month of pregnancy, the baby is usually lying upside-down in the womb. The head sinks down firmly into the mother's pelvis, ready for birth

2.) In the first stage of labour, which lasts about nine hours, the muscular walls of the womb contract, pressing the head of the baby against the cervix.

3) As contractions continue, the pressure of the head of the baby slowly stretches the cervix open. These contractions grow longer and more intense.

4) At the end of the first stage, the cervix is open. The amniotic sac breaks, releasing fluid. This is 'the breaking of the waters'.

5) The head is forced into the vagina. Once it passes between the bones surrounding the birth canal, the mother is generally told to begin to bear down to push the baby outwards.

6) In the second stage of labour, which lasts half an hour to two hours, the baby is born. As it leaves the birth canal, its head faces the mother's back. Her backbone is forced down to let the baby pass.
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7) After the head of the baby has emerged, the shoulders, which are turned, slip out easily. The rest of the body is quickly delivered. With the baby's first cry, breathing begins. The umbilical cord is cut.

8) In the final stage of labour the womb discharges the placenta and the remains of the umbilical cord, which are forced out through the vagina. The womb returns to normal size about 10 days after the birth.

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