Maternal Diseases And Disorders

Chronic infections or the deleterious effect of venereal diseases such as syphilis, produce their worst effects in the larger stages of foetal life and may affect mental development. High blood pressure, diabetes and blood incompatibilities may affect foetal development. The increase in miscarriages and maternal or foetal death are directly related to the high blood pressure of the pregnant mother. Infants of diabetic mothers have a relatively high proportion of infant mortality and abnormalities, particularly of the respiratory and circulatory systems.

In addition, an incompatibility can occur between the blood types of the mother and child. Rh blood incompatibility is the most frequent and destructive. If the mother is Rh negative and the foetus has a Rh positive blood group from the sperm cell of the father, infant death can occur due to destruction of red blood corpuscles. This is because antibodies are produced in the blood of the Rh negative mother. These toxic antibodies are incompatible with the fetal blood causing probable death of the fetus unless the condition is diagnosed and precautions are taken.

Maternal  sensitivity to Rh positive foetus antigens increases with successive pregnancies and although the first pregnancy might be normal, later ones are less likely to be so.

The Main Effects Of Adverse Conditions

The foetus is affected by adverse conditions depending on their timing and the development stage of pregnancy. Since the various organ systems begin and end their prenatal development at different times, their sensitivity to the different factors, varies over time. The most vulnerable period for the brain is from 15 to 20 days, for the eyes from 24 to 40 days, for the heart from 20 to 40 days and for the legs from 24 to 36 days. Normally, the organism is less vulnerable before implantation and after the beginning of the foetal stage. Mishaps during the embryonic period, when the different organs are developing, could have drastic effects.

Parental conditions that can affect a child’s development are:

•           Maternal diseases and health
•           Drugs taken by the mother
•          Maternal diet
•          Maternal emotions
•          Maternal age

Since individual factors influence specific development processes they produce specific patterns of the developmental deviation. For example, German measle in the first trimester affects mainly the heart, eyes and brain. The physiological status of the mother, such as maternal nutrition, uterine conditions and hormonal balance will not only affect prenatal development but may intensify the adverse effects of the various drugs taken by the mother.

Prenatal Conditions And Their Effect On Development

There are many factors which influence development and cause deviation or produce malformation in the foetus. These include maternal diseases, blood disorders, diet, irradiation, drugs, hormones, oxygen level and temperature. In addition, maternal characteristics such as age, emotional state and number of children, are known to have an influence on prenatal development. Adverse prenatal and birth factors can result in gross physical defects or mental impairments. These impairments profoundly affect the life experiences of the responses of those around. How does a parent treat a child with physical or mental deficiency? Is the parent more anxious and protective or more rejecting? What happens to parent-child interaction? How is the emotional bond between parent and the child affected? Thus it is for sure influences of adversities in mother’s well being will reach the child. Prenatal development is very crucial stage of life where it starts developing structures and behavior based on many factors and inputs from the mother. 

The Period Of Foetus – Two months to birth

The period of foetus is the third stage of prenatal development. It extends from the end of the second month to the time of birth, which normally occurs at the end of around 280 days. It is characterized chiefly by growth and development, as all the body parts and structures have already been established in the period of embryo. At the end of the third month, the foetus measures around ten inches and weight about 250 gram. By the end of the eighth lunar month it measures about 16 inches and weighs about 2 kg. At full term, that is, 280 days, the foetus measures about 19 inches and weighs 3 to 3.5 kg. However, there are large individual differences in these estimates. The estimate may vary on various accounts say for example, the mother is weak or mother takes less nutrition than she is supposed to, or her emotional status.

The Period Of Embryo - Two weeks to two months

The second stage of pregnancy is the period of embryo, it extends from the end of the second week to the end of second month. It is a time of rapid change and by the end of the this stage, when you are barely aware of your pregnancy, the embryo has developed into a miniature human. During the period of embryo, special structures form to provide nourishment and protection until the baby is born. These are the placenta, umbilical cord, amniotic sac and amniotic fluid, all inside the uterus. The umbilical cord is attached to the embryo’s abdominal wall at one end and the placenta at the other hand. The cord is composed of blood vessels. There are no nerve cells in the cord thus making transfer of the mother’s emotions to the embryo impossible. In due course, the chord becomes about twenty inches long and as thick as a man’s finger. The amniotic sac contains amniotic fluid which protects the embryo and later the foetus from external shocks and injuries. Just before birth the sac breaks, releasing the amniotic fluid which helps to lubricate the passageway for delivery. The embryo is nourished through the maternal blood flow into the placenta from the arteries in the uterine wall, thus permitting oxygen, water and food material in the mother’s bloodstream to be transported through the umbilical cord to the embryo. Through the same cord, embryonic waste products are filtered back.

The Period Of Ovum - Conception to two weeks

This stage extends over a span of two weeks from the time of fertilization until the fertilized egg (now called the zygote) reaches the uterus. During this period, the foetus-to-be retains its egg-like appearance. Its size, which is no larger than a pinhead, remains practically unchanged because it receives no external nourishment. However, marked changes take place in the internal structure of the zygote. The single cell divides repeatedly until it forms a globular cluster of cells. The outer layer develops into accessory parts which protect and nourish the embryo. The inner cluster of cells later develops into the embryo itself. This cell division takes place as the fertilized ovum is carried down the fallopian tube to the uterus. Normally, fertilization occurs in the fallopian tube. When the zygote reaches the uterus it floats there for some tome before attaching itself to the uterine wall. It has to survive on the little yolk within the egg cell. When the ovum finds a place inside the uterus, it shoots out feelers which push their way through the blood vessels to tap nourishment. This process is called implantation and occurs about ten days after fertilization. Occasionally, the ovum does not move down to the uterus and becomes attached to the wall of the fallopian tube. This is called tubal Pregnancy and is a condition, which can endanger the mother’s life.

The Phases of pregnancy

From the onset of menstruation in all girls, when a mature egg cell is released from the ovary, the lining of the uterus begins to undergo changes in preparation to receive the fertilized egg. This is carried out by two hormones, estrogen and progesterone, produced in the ovary. These two hormones prepare the uterine’s wall by increasing the blood vessels and glandular system of the wall so that it becomes a thick soft cushion capable of housing the fertilized ovum and secreting nourishment. If no fertilization takes place, all this preparation is eliminated from the body in the form of menstrual flow.

        As soon as you feel that a baby might be on the way, you should consult a doctor. Follow the doctor’s advice faithfully on the routine and specific tests that she prescribes and the precautions you may have to take. Get her to explain to you the natural course of pregnancy and place complete trust in her prescriptions. Don’t take medicines recommended by friends and neighbors to overcome discomfort, particularly during the first three months. Medicines must be taken only under medical supervision as they can be very harmful to the baby growing inside you. The nine months pregnancy is divided into three periods of three months, each known as trimesters. Each trimester demands its own specific medical care, immunization routine, scans, and so on.

Twins

It is said that the birth of twins runs in families and they are usually born in alternative generations in families which have a history of twins. There are two types of twins: fraternal twins and identical twins. In the case of fraternal twins, instead of one ripe ovum being released in the monthly cycle, two ripe ova are released from the ovary into the fallopian tube. These two eggs are fertilized by two different sperms and thus two different zygotes develop simultaneously in the uterus. Since they are two different zygotes, they may be of the same sex or of different sexes, and they resemble each other only as much as two ordinary siblings do. In the case of identical twins, only one egg is fertilized but at the time of the first cell division, they separate and two foetuses develop instead of one. Since they they have developed from the same zygote, the foetuses are exactly alike and of the same sex.