Events that take place during conception
Conception usually takes place approximately two weeks after the commencement of the last period. The due date is calculated from day 1 of the last period and counted ahead for 40 weeks.
During sexual intercourse, sperm travel up the uterus and into the fallopian tubes where they unite with the ovum or egg from the female. The united sperm and ovum form a single cell structure called a zygote. Multiple zygotes may occur if more than one egg is released and fertilized OR if the fertilized egg splits into two.
The zygote usually has 46 chromosomes, 23 of which originate from the biological mother and 23 from the biological father. These chromosomes determine the baby’s sex and physical traits.
Soon after fertilization, the zygote travels down the fallopian tube toward the uterus. It simultaneously begins to divide to form a morula, which is really a cluster of cells resembling a tiny raspberry.
By week 4, implantation usually takes place. The baby is now called a blastocyst because it is now a rapidly dividing ball of cells. Implantation takes place when the blastocyst begins to burrow into the lining of the uterus.
There is an inner group of cells within the blastocyst which will become the embryo. The outer layer of cells will give rise to part of the placenta, which will nourish the baby throughout the pregnancy. The blastocyst begins to produce a hormone called human chorionographic hormone or HCG.
During the third week after conception, the levels of HCG hormone produced by the blastocyst quickly increases. This sends a signal to the female ovaries to stop releasing eggs and produce more estrogen and progesterone. As the levels of estrogen and progesterone increase, the menstrual period will stop. This is usually the first sign of pregnancy.
Formation of the embryo
The embryo forms during this period. It consists of three layers – a top layer, middle layer and inner layer.
The top layer is called the ectoderm. It will give rise to the baby’s outermost layer of skin, central and peripheral nervous systems, eyes, and inner ears.
The middle layer of cells is called the mesoderm. The baby’s heart and a primitive circulatory system will form in this layer of cells. This is also the location which will also serve as the foundation for baby’s bones, ligaments, kidneys and much of the reproductive system.
The inner layer of cells or the endoderm is the location from which baby’s lungs and intestines will develop.
Development of the placenta
The placenta is a round, flat organ. It is the route by which nutrients are transferred to the baby from the mother. It also moves wastes out of the baby and excretes via its blood supply.
Organs which form during month 1
Body parts begin to take shape during month one:
A primitive face will take form with large dark circles for eyes.
Structures necessary for the development and ears begin to form.
The mouth, lower jaw, and throat begin to develop.
Blood cells take shape and blood circulation begins.
The tiny “heart” tube will beat 65 times a minute by the end of the fourth week.
Just four weeks after conception, the neural tube along baby’s back begins to close. The baby’s brain and spinal cord will develop from the neural tube.
Small buds appear that will soon become arms.
Baby’s body begins to take on a C-shaped curvature.
By the end of the first month the baby is smaller than a rice grain and is about 1/4 inch long.
The importance of folic acid during month one of development
Folic acid is a B vitamin which is necessary for the formation of new cells. Cells are the building blocks of life and the foundation units of all body parts like the brain, bones, eyes, skin, hair, and nails.
The first month of pregnancy is one of the baby’s most important periods of development since its cells are rapidly dividing and forming new organs. Pregnant women should take folic acid supplements during this important stage since it supports development of the neural tube which gives rise to the brain and spinal cord. Folic acid helps to prevent birth defects in the baby’s brain and spine.
The Centers For Disease Control And Prevention (2019) recommends that all women of reproductive age should take 400 mcg of Folic Acid daily and eat foods rich in folate.
Ways that pregnant women could get folic acid
1. Eat foods rich in folate. These include:
– Leafy green vegetables, such as spinach
– Citrus fruits, such as orange juice
2. Eat foods fortified with folate or folic acid (check the labels)
3. Taking a vitamin that has 100% of the recommended daily dose of folic acid in it – 400 mcg.
4. Taking 400 mcg of folic acid daily.