First Trimester Of Pregnancy
The first trimester of pregnancy is considered to be the most important out of the three trimesters of pregnancy. The reason is because these twelve weeks are considered to be the time during which all the vital organs of the embryo start to form and to function. Not only this; the foetus also lays a ground for itself in the uterus. In this article, we shall discuss about the symptoms of the first trimester and then a week-by-week summary of the first trimester will be presented.
There is a variety of first trimester pregnancy symptoms that a woman notices. For example, the woman complains of abdominal cramping when the groups of newly formed cells start to invade the uterus and locate themselves over there. After that, breast changes are very frequent and the woman might notice breasts getting swelled up, sore and tender. Associated with them will be nipples which will be darkened. Morning sickness is a famous symptom which can be felt throughout pregnancy but most commonly it is seen from week 4 to 12. Extreme fatigue is felt from the fourth or fifth week because the embryo is trying really hard to grow in size at that time.
Now the development in the first trimester pregnancy-week by week is detailed as follows:
Week 1: This week is counted from the first day of the Last Menstrual Period, so nothing of significance is happening in this week and woman normally notices her periods.
Week 2: The body is about to ovulate in this week.
Week 3: The sperm is met by your ovum and fertilization takes place. The zygote than converts into an egg and the egg continues to grow further into a yolk sac.
Week 4: The egg reaches and settles at a place in the uterus.
Week 5: The embryo here grows and divides into three layers; the outermost layer or the first layer is known as neural tube and will form the nervous system. The layer 2 (middle layer) is responsible to develop the circulatory system, heart, bones, muscles, kidneys and organs of reproduction; while the inner most layer develops into liver, pancreas, intestines and bladder.
Week 6: The heart of the baby now starts to beat and along with it, the brain divides into fore, mid and hind brains. The forebrain is dedicated to reasoning and memory, mid-brain for signals to organs and limbs, and hind brain is for the muscle movement and breathing.
Week 7: This week is dedicated to the formation of eyes, ears, nostrils and the development of limbs.
Week 8: In this, further specialization of the elbows begins and fingers and toes are formed.
Week 9: In this week, eyelids and tongue start to develop.
Week 10, 11 and 12: Each organ now gets more refined and more specialized in its function. The urinary and genital systems also develop and acquire functioning. Hence, by the highlights of all these weeks of first trimester, we can easily conclude that the first trimester of pregnancy is its most important phase.