Definition and Overview
Commonly used to refer to gestation in humans, pregnancy is the development of a fetus within a woman’s womb. Typically, human females carry a single fetus within the womb and give birth to one offspring, but there are also instances when a female carry and give birth to two or more offspring. Such an instance is called as a multiple pregnancy.
The fetus develops within the woman’s uterus and is due for birth at around 38 weeks after conception. The due date of the fetus is predicted forty weeks after the last occurrence of menstrual period (in women who have a four-week menstrual cycle length).
After conception, the woman carries an embryo, an early form of the developing offspring, for around eight weeks. After this time, the embryo is called a “fetus” until birth.
The period of pregnancy in human females is divided into three trimesters. The first trimester, the first three months of the pregnancy, is typically the riskiest part of the pregnancy, since more women miscarry during this period. The second trimester, which spans the fourth to sixth month of the pregnancy, is when the growing fetus is observed by a qualified medical professional, through tracking of symptoms or using medical instruments that allow the professional to peek inside the womb. On the third trimester, which spans the beginning of the seventh month until childbirth, is marked by further development of the fetus, as well as the fetus’ fat stores to prepare it for birth.
Human babies are born during what medical professionals call the “point of fetal viability.” At this point of its growth and development, it is possible for the fetus to survive life outside of its mother’s womb. This point occurs during the latter part of the second trimester and the early part of the third trimester. If the fetus is born before the point of fetal viability, there are higher chances for it to be born with serious medical conditions, or worse, dying.
Miscarriage is defined as the natural death of the embryo or the fetus. The term “abortion” implies more deliberateness in the termination of the fetus and is currently illegal in some countries. Stillbirth, on the other hand, is a term used when a pregnant woman gives birth to a dead infant. In a more strict usage of the term “stillbirth,” the fetus must have survived within its mothers womb after the first 28 weeks of pregnancy.
Cause of Condition
The conception of human fetus can be achieved by two distinct methods: sexual intercourse or assisted reproductive technology. In the case of the latter method, a qualified medical professional will administer (or assist in the performance of) artificial—or in some cases, partially artificial—means. In most cases, people with infertility issues seek reproductive technology in order to help them conceive.
Assisted reproductive technology can include medication to stimulate and improve the development of follicles in a woman’s ovary, which involves the use of ingredients that release the hormone gonadotropin. Artificial insemination is also a popular artificial reproductive means and typically involves the artificial (i.e., not done naturally, without the direct involvement of male genitalia) placement of sperm into a woman’s cervix or uterus. Artificial insemination can be quite low-tech, and usually performed by the woman in private.
Another common reproductive technology is in vitro fertilization, which involves the fertilization of an egg by a sperm outside the woman’s body. The product of the fertilization process, the embryo, will be inserted back through the woman’s vagina or uterus.
When a human female is pregnant, she experiences several “telltale” signs that point to her condition. Common symptoms include feeling nauseous and vomiting, frequent periods of excessive fatigue, unusual cravings for certain foods, and frequent trips to the bathroom at night to urinate.
These symptoms typically occur during the first couple of weeks after the egg is fertilized. Many medical professionals believe that these symptoms are not universal and are not strictly diagnostic by themselves—just taking these symptoms as sure signs of pregnancy can be quite presumptive.
The best way to tell if a woman is pregnant—especially during the first few weeks of conception—is to check the presence of hCG or human chorionic gonadotropin in her blood and urine. Her vagina, vulva, and cervix also darken (known as Chadwick’s Sign) and a higher basal body temperature is maintained over a period of two or more weeks after ovulation.
Who to See and Types of Treatments Available
To confirm a pregnancy, it is highly advised to go to an OB/GYN or a specialist in obstetrics and gynecology. The OB/GYN can correctly diagnose a pregnancy through blood and urine tests, as well as other biological markers.
The OB/GYN, especially one that specializes in maternal-fetal medicine or perinatology, is also qualified to dispense diagnosis, advice, and medication regarding the mother’s and fetus’ health during the period of pregnancy.
Typically, an OB/GYN will prescribe vitamins and several lifestyle changes to observe to keep the mother and fetus healthy.
- The Johns Hopkins Manual of Gynecology and Obstetrics http://books.google.ca/books?id=4Sg5sXyiBvkC&pg=PR232
- Women’s Health Information http://www.womens-health.co.uk/miscarr.asp
- Handbook of Brain and Behaviour in Human Development http://books.google.com/books?id=FzyPozUyKPkC&pg=RA1-PA416
- Human Reproduction http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777570