Pregnancy occurs when a male sperm meets and fuses with a female ovum to form a zygote. It is the time period between conception and birth inside the body of a woman. This period normally takes nine months in women. There are two types of pregnancies: normal pregnancy and ectopic pregnancy. Normal pregnancy occurs when the male gamete (sperm) fuses with the female gamete (ovum) in the fallopian tube and the zygote implants itself on the uterine wall. This way, the fetus develops and it is eventually pushed out through the birth canal during birth.
On the other hand, ectopic pregnancy occurs when fertilization takes place in the fallopian tube and the zygote is implanted on the walls of the fallopian tube. Since this is a complicated process, a surgical operation is required at birth so as to remove the baby from the side of the fallopian tube.
During pregnancy, several hormones play a balancing role to make sure that the development of the fetus is normal. During the first four months of pregnancy, the ovaries produce progesterone hormone that maintains the pregnancy. However, after the four months, the developed placenta starts to produce the hormone. Under legal grounds, pregnancy can be terminated either through a surgical means or through artificial hormonal imbalance as explained by the Gynaecology Centres Australia. (See http://gcaus.com.au/)
The fetus is cushioned from shocks inside the womb of a woman by amniotic fluid contained in a sac like structure called the amniotic sac. Nutrients are supplies to the fetus through the umbilical cord.
During pregnancy, a woman experiences many body changes. Initially, she will have smooth face but at some point black sports may fill her face.
The end of pregnancy is signaled by waves of muscular contractions in the uterine wall and downwards towards the birth canal (vagina). This results to labor pains. Labor pains are triggered by the secretion of oxytocin hormone.