Pregnancy can be broken down into many different stages. The first stage begins with conception, and, in most pregnancies, the last stage ends in birth. In a full-term pregnancy, there are nine full months. The baby has new developments at each stage in pregnancy.
In the beginning stages of pregnancy, ovulation, egg release, fertilization and implantation occur according to an article on AmericanPregnancy.org. Ovulation occurs when a mature egg is released from the ovary, pushed down the fallopian tube and is then able to be fertilized. Fertilization occurs when a sperm fuses with the released egg. After the sperm has been fertilized an embryo develops. This process is conception which is the first step in pregnancy.
The first trimester of pregnancy begins approximately two weeks before conception, and is usually calculated using the first day of the woman's last menstruation cycle. The second month of pregnancy is crucial in fetal development. The baby's heart will begin to beat. According to BabiesOnline.com, the upper and lower limbs will appear, the joints are formed, and many vital organs, including the brain, stomach and lungs are evident. The baby's bones begin to harden during the third month according to FamilyResource.com. Eyelids, ears and genitalia are all formed during this month. Also, the baby's heart beat can be heard with special equipment.
The fourth month begins the second trimester. The baby is now making its own insulin and bile. Tests can be run during this month to test for Down Syndrome, gestational diabetes and spinal defects according to FamilyResource.com, but some of these tests can also be done in the first trimester. The baby moves around much more during this month, but these movements are not usually noticeable until closer to the end of the second trimester. There are no new organs formed at this point, but gender is visible if the baby is in a cooperative position during the ultrasound. According to PlannedParenthood.org, eyebrows and eyelashes are now forming, and the baby is practicing its breathing for birth. Also, the baby's taste buds begin to form.
The fetus can hear the mother's heart beat in the seventh month of pregnancy according to Pregnancy.More4Kids.info. The baby's eyes are open and eye lashes are growing. There is not as much room for the baby to move around as there was in previous months. The baby has gained weight, and around the seventh month is about 11 inches long. By the eighth month of pregnancy, fine hair that grows on fetuses during gestation, called lanugo, starts falling off according to PlannedParenthood.org. In the ninth month, the due date is a few weeks away. The baby's organs are finished forming, but the baby is continuing to grow. According to BabyCenter.com, by full-term, babies range from less than 5 lbs. to more than 9.
The woman's cervix begins to thin and open or dilate toward the end of pregnancy. According to PlannedParenthood.org, this happens to prepare for delivery. Also, during this time, many women experience contractions, which cause the upper part of the uterus to tighten and the lower part to stretch to help the baby pass through the birth canal. In some cases, women may not go through all of these steps, and a cesarean-section will be performed to deliver the baby. A cesarean-section, better known as a C-section, is a surgical procedure on the woman's abdomen to deliver a baby. After the baby is born, the placenta and other tissues are also delivered.