Introduction
Prenatal period refers to the period of pregnancy from the time after fertilization when the embryo is implanted in the uterus of a woman or during abnormal circumstances in the fallopian tube or cervix in which case it can lead to ectopic pregnancy. This period proceeds to the time when the woman gives birth after nine months. The period is generally broken into three major categories or trimesters. Each of these periods takes about three months with each stage being accompanied by major change.
First trimester
This stage starts when fertilization takes place in the fallopian tube. In the normal circumstances the embryo is implanted in the lining of the uterus. Most women experience slight bleeding during implantation as well as cramping. This is of no serious concern if no bleeding is observed. It has also been observed that the outer layer covering the embryo increase to form placenta. The placenta connects to the umbilical cord to create the passage of important nutrients from the mother to the embryo and this makes the embryo grow tremendously. Morning sickness occurs in most pregnant women during this trimester and most miscarriages can occur at this stage. The first trimester proceeds to the end of the third month. (Bailey, 1970)
Second trimester
This period occurs from the start of the fourth month to the end of the sixth month. The majority of women are reported to be feeling more energized. Most women add on weight and morning sickness greatly decreases and finally fades away. The chances of miscarriage reduce greatly and major structures develop. These include; brain, feet, hands and head which continue to grow. The length of the fetus is about 30mm and the heart can be felt beating through sonograph.
The movement of the fetus is felt commonly at the end of the fourth month. This is referred to as quickening. The placenta becomes fully functional and the fetus starts urinating as well as making its own insulin. The teeth start to form in the gum of the fetus and one can recognize reproductive organs and distinguish whether the fetus is a male or a female. (Parens, 2000)
Third trimester
This period takes place at the onset of the seventh month to the end of the ninth month. The pregnant woman experiences final weight gain. The fetus makes regular movement which is observable. The abdomen of the pregnant woman expands and the navel becomes convex. This makes the woman uncomfortable and the bladder becomes weak in controlling urine. She also experiences backache. There is increased movement of the fetus which is at this time stronger.
The eye and muscle function as well as the brain of the fetus improve greatly. Sometimes when the fetus roll the mother can feel and this may cause discomfort especially when the fetus is near the mother’s ribs. If a baby is born prematurely at this stage, it can survive if it is well attended although it can still cause ill-health to the baby in future. (Papalia, 2003)
References
Bailey H. (1970): The prenatal epoch: Weisler.
Papalia D. (2003): Human Development: McGraw-Hill education.
Parens E. (2000): prenatal testing and disability rights: Georgetown university press.