Pregnancy is the period of prenatal development during which a female carries one or more live offspring (known as the embryo and later the fetus) from implantation in the uterus through gestation. It is often viewed as one of the most spectacular parts in a woman’s life, filled with joy, anticipation, and fear.
There are multiple ways for a woman to discover she is pregnant, the most common way is the absence of an expected menstrual cycle. Once the pregnancy is detected the important factor is that the mother obtains secure prenatal care. During prenatal care, a woman’s doctor, midwife, or health care specialist will perform a series of tests to ensure the health of both the mother and the baby throughout the duration of the pregnancy.  Aside from prenatal care, there are other important steps for an expecting mother to take to ensure the health of her baby, such as quitting smoking, limiting her caffeine intake, or recruiting someone else to clean out the litter box.
If a woman does not take special care during her pregnancy it could endanger her own life as well as the life of her baby by resulting in conditions such as eclampsia, or causing premature birth or a miscarriage. As long as a woman seeks professional medical help and takes special care of herself during the pregnancy, it is likely that after nine months she will deliver a beautiful and wonderfully healthy baby.
- 1 Diagnosis
- 2 Prenatal Care
- 3 Precautions
- 4 Complications
- 5 Stages
- 6 References
Pregnancy symptoms are important to understand because each symptom could be related to something other than pregnancy. Many symptoms are similar to those before a menstrual cycle or during premenstrual syndrome(PMS). Some women begin to experience signs or symptoms of pregnancy within a week of conception. Others may develop symptoms over a period of a few weeks. Some women, however, may not experience any symptoms throughout the duration of their pregnancy.
- Missed Menstrual Cycle:
The most common indication of pregnancy is the delay or absence of an anticipated menses. When a woman becomes pregnant, she should miss her next period. Many women can bleed during pregnancy, but it will be shorter or lighter than a normal period.
- Implantation Bleeding:
Implantation bleeding can be one of the earliest pregnancy symptoms. Approximately six to twelve days after conception, the embryo implants itself into the uterine wall. As a result, some women will experience spotting accompanied with possible cramping.
- Fatigue or Tiredness:
Feeling especially tired or fatigued is a pregnancy symptom that may start as early as the first week of pregnancy.
Lower backaches are a symptom that may occur early on in pregnancy; however, it is common to experience a dull backache throughout the entire process.
Possible headaches during early pregnancy are caused by the sudden increase of hormones in a pregnant woman’s body. 
- Mood Swings:
Mood swings can be quite severe for women in early pregnancy and may include feelings of euphoria followed by depression or sadness. 
- Food Cravings:
While not all women crave pickles and ice cream, many women find that they have a craving for unusual foods during their pregnancy. Such cravings can last throughout the duration of the pregnancy.
- Augmented or Tender Breasts:
Augmented (swollen) or tender breasts are a symptom of pregnancy which may develop as early as one to two weeks after conception. Women may notice changes in their breasts feeling tender to the touch, sore, or swollen. Some women will also experience darkening of the areolas (the skin around the nipples.)
- Frequent Urination:
Often six to eight weeks after conception, pregnant women find themselves making a few extra trips to the bathroom.
- Morning Sickness:
Nausea or morning sickness is a well-known pregnancy symptom that will occur between two to eight weeks after conception. Some women are fortunate in not having to deal with morning sickness at all during their pregnancy, while others will feel quite nauseous throughout. 
For a woman experiencing these symptoms it is important to take a pregnancy test to either confirm or deny suspicions of pregnancy. Pregnancy tests aim at identifying human chorionic gonadotropin (hCG), a hormone produced soon after fertilization and ovule implantation in the womb which allows the body to recognize pregnancy. Testing for the presence of hCG is done either through a blood or urine test and is the most widely used method for diagnosing a pregnancy in its early stages.
HCG levels vary throughout pregnancy. They increase by at least sixty-six percent every forty-eight hours, arriving at the maximum peak between fifty and seventy-five days of pregnancy. In second and third pregnancy trimesters, the hCG levels are lower. The presence of hCG in the bloodstream makes pregnancy diagnosis very likely. However, there are three other tests commonly used to verify a woman’s pregnancy.
- Presence of Fetal Heartbeat:
The presence of fetal heartbeat can be detected by sonar within ten to twelve weeks of pregnancy and with a stethoscope at seventeen to nineteen weeks. Doctors must be careful not to confuse the baby’s heartbeat with the mother’s during examination. This is not too difficult as the baby’s heartbeat is between one hundred twenty and one hundred sixty beats per minute, while the mother’s heart rate is considerably lower.
- Identification of Fetal Movements:
After the twelfth week of pregnancy, fetal movements can be detected by the examiner simply placing their hand on the mother’s womb. If the pregnant mother is obese, perception of fetal movement will occur at a later stage.
- Viewing the Fetus:
visual identification of the baby can occur via transvaginal echography at week six of the pregnancy, or through the abdomen at week eight. Transvaginal echography is employed not only for diagnosing the pregnancy, but also for identifying abnormalities. 
Prenatal development requires care to ensure the health of any mother and baby during pregnancy.  Such care is provided either by a doctor, healthcare specialist, or midwife.  Prenatal care includes education on pregnancy and childbirth, as well as counseling and support for the mother-to-be. It also allows the health care provider to follow the progress of the baby’s development and provides the mother with the opportunity to ask questions about her pregnancy.  Women who keep regular appointments with their health care provider during pregnancy deliver healthier babies, who are less likely to be born prematurely or have other serious problems related to pregnancy. 
First Prenatal Care Visit
A woman’s first prenatal care visit with her doctor is to determine her general health and alert the health care provider of any risk factors that may affect the pregnancy. At the first prenatal visit, the doctor will:
- Set the due date
- Learn the mother’s health factors
- Examine the medical history of both the mother and father’s families
These goals will be achieved by thorough questioning and several tests administered by the health care specialist. It is important at the first meeting for the mother to inform her doctor of any drugs, operations, or other health related factors that she was involved in. From these tests and questions the doctor will be able to assess what the woman’s pregnancy will be like, including difficulties and other possible problems. 
Additional Prenatal Care VIsits
After the initial visit, the patient will have to return at regular intervals to ensure the proper development and health of her baby. The following is an idea of what a woman’s schedule could be as to prenatal visits during the nine months of her pregnancy:
- Weeks 4-28: one visit per month (every four weeks)
- Weeks 28-36: two visits per month (every two to three weeks)
- Weeks 36- delivery: one visit per week
A woman who has a chronic medical condition or is having what has been deemed by her doctor a “high-risk” pregnancy may have to see her health care provider more frequently than the schedule suggested above. It is important for any expecting woman to attend all her scheduled prenatal appointments, even if she is feeling fine. 
Tests Performed at Prenatal Care Visits
As mentioned before, a woman’s health care specialist will have to perform a series of tests to better understand the health of the mother and of her baby. Some of these tests could include:
- Physical exam:
A typical physical exam includes the doctor weighing the mother and checking her blood pressure, heart, lungs, and breasts to ensure that there are no irregularities that should be addressed.  In later stages of pregnancy, the doctor checks the woman’s hands, feet, and face for swelling. 
- Pelvic Exam:
During the pelvic exam, the doctor will take a Pap smear to screen for cervical cancer and cultures are taken to detect the presence of any STDs, such as gonorrhea and chlamydia. The doctor will also perform a bimanual internal exam to determine the size of the uterus and pelvis. This exam will also check for any abnormalities of the uterus, ovaries, or fallopian tubes. The two tests mentioned above often occur at the first meeting and only diluted versions of these tests will follow after.
- Doppler Exam:
The health care specialist may use an instrument called a doppler, which uses ultrasound waves, to listen for the baby’s heartbeat. Usually a doppler cannot detect a baby’s heartbeat before ten to twelve weeks of pregnancy.
The doctor may also utilize ultrasound to look at the baby. This monumental amazing experience allows the doctor to check the baby’s heart beat, as well as to verify its due date.
- Complete Blood Count (CBC):
This test screens for blood disorders such as anemia.
There are many recommended tests to check for STDs such as:
- AIDS Test:
tests for the presence of the disease caused by HIV
a screen test that checks for syphilis
There are also tests to check for the presence of other diseases like: Rubella: a test that screens for immunity against German measles. Varicella: a test that screens for immunity against chickenpox. HBsAg: a test that screens for hepatitis B (a liver infection) that is transmitted through contaminated needles, blood, saliva, semen, or vaginal fluid. Urinalysis: during this test, the pregnant woman urinates into a cup. The urine will then be tested for kidney disease, bladder infections, and high levels of sugar which might indicate diabetes.
There are also genetic tests that must be conducted to ensure the genetic health of the baby. Such tests include:
- Type and Screen Blood Test:
This test determines a person’s blood type and Rh factor (a protein on the surface of blood cells that causes an immune system response). Everyone is either Rh negative (the blood doesn't contain Rh factor) or Rh positive (the blood contains Rh factor; 85% of people do). Having either is fine, but if the mother's blood is Rh negative and your father's blood is Rh positive, the baby's blood type may not match the mother’s (it may be Rh positive). This can be a problem during delivery or even cause a miscarriage because the mother’s body could produce antibodies to protect itself from the "foreign" substance. This phenomenon is called Rh incompatibility and it occurs in about 15% of all pregnancies. If a woman’s partner's blood is Rh+, and hers is Rh-, she will be given an injection of Rh immune globulin (called Rhogam) during the twenty-eighth week of pregnancy to prevent the development of antibodies that could be harmful to her baby. She will also receive the injection during invasive procedures or if she has any significant bleeding during the pregnancy. Additionally, an injection of Rhogam is given after delivery if the baby possesses Rh+ blood.
- Genetic Tests:
Depending on ethnic background and medical history, the mother may also be tested for sickle-cell anemia, Tay-Sachs disease, and Thalassemia. Africans, Jews, French Canadians, and people of Mediterranean descent are most at risk for these illnesses. All of these diseases can be passed onto the baby because of defective genes that the parents may carry, even if the parents don't have the disease. The health specialist may also offer a test for cystic fibrosis, an inherited disease that can affect breathing and digestion for the baby if both the woman and her partner are carriers. 
Once she are sure she is pregnant, it is important for the woman to take steps to ensure that both she and her baby remain healthy throughout the pregnancy and the birthing process. Such steps include avoiding certain things that could be hazardous and cause birth defects; these things are called teratogens.  A few examples of teratogens are:
Consuming alcohol during pregnancy may cause Fetal Alcohol Syndrome (FAS). Babies who are born with FAS may grow more slowly, have learning problems, or have abnormal facial features. There s no cure for problems caused by FAS. Alcohol is an ingredient utilized in many over-the-counter medications; for example, some cough medicines’ composition is twenty-five percent alcohol. Therefore, it is very important for pregnant women to always read the label or consult their doctor before taking any medication.
Smoking cigarettes can lead to very serious health problems. Women who smoke during their pregnancies usually give birth to babies that weigh less than those of women who don’t smoke. Low birth weight babies are more likely to have health problems such as: being more susceptible to infections, having trouble keeping warm, having breathing problems, and being more susceptible to Sudden Infant Death Syndrome (SIDS). Research shows that exposure to second-hand smoke can also cause SIDS and other health problems for babies.
Caffeine is a stimulant that affects each person differently. It can cause nervousness, irritability, anxiety, irregular heartbeats, and problems sleeping. Caffeine’s effect on unborn babies is still under investigation, but some scientists believe it can cause the birth of premature babies or babies with birth defects. It is important for pregnant women to not only cut down on their direct caffeine intake, but also to check the ingredients in non-prescription medicines such as headache, cold, and allergy pills for traces of caffeine.
- Food Additives:
Food preservatives should be avoided by pregnant women and can be found in processed foods such as hot dogs, foods containing sodium nitrate like ham or bacon, or on the peels of fruits and vegetables.
- Medications and herbs:
Certain herbs and medicines can be harmful to an unborn baby and therefore a woman who is expecting should first check with her doctor before utilizing any medications.
- Fish and Seafood
Fish and seafood are excellent low-fat sources of many nutrients and are an important part of a healthy diet. However, some types may contain high levels of mercury which could be harmful during a pregnancy. Doctors suggest that pregnant women eat no more than twelve ounces of cooked fish a week; avoid eating shark, swordfish, king mackerel, or tilefish; and limit their intake of albacore tuna to once a week.
- Saunas and Hot Tubs:
Pregnant women should avoid saunas and hot tubs that maintain a temperature higher than normal body temperature. This would have the potential to cause overheating, and could negatively affect the development of the baby.
Fetal solvent syndrome is caused by exposure to chemicals and puts babies at risk for major birth defects. Chemical exposure varies from location to location, so it is important for a pregnant woman to talk to her doctor to determine appropriate precautions based on their location.
Toxoplasmosis is a condition caused by a parasite found in cat feces, plant soil, and raw or undercooked meat. The parasite can cause brain damage in a developing baby if the mother becomes infected during pregnancy. Doctors and scientists strongly suggest that pregnant women find someone else to change the litter box, use gloves when gardening, wash dirt from all fresh produce before eating, and cook all meat to at least medium or well-done. 
A miscarriage is the loss of a pregnancy in the first twenty weeks. About fifteen to twenty percent of known pregnancies result in miscarriage, and more that eighty percent of miscarriages happen before twelve weeks. Most first-trimester miscarriages are believed to be random events caused by chromosomal abnormalities in the fertilized egg that prevent the embryo from developing. Although spotting or bleeding is not uncommon in early pregnancy, it is important for a woman experiencing such symptoms to contact their doctor because they are the first signs of a miscarriage. If a woman’s doctor suspects a miscarriage, they will most likely order an ultrasound or possibly a blood test.
- Premature Labor and Birth:
A woman who begins having contractions, causing her cervix to dilate (open) or efface (thin out), before she reaches her thirty-seventh week of pregnancy is experiencing what is called premature labor. When a baby is delivered before thirty-seven weeks it is called a preterm baby and is considered to be born prematurely. About twelve percent of babies born in the U.S. are premature. Premature birth can cause serious health problems or even be fatal for the baby if it is born too early. The more mature a child is at birth, the more likely it is to survive and be healthy.
A woman’s amniotic sac is filled with amniotic fluid that supports and protects her developing baby. A condition where there is too little amniotic fluid in the sac is called oligohydramnios. Reports say that about eight percent of pregnant women have low levels of amniotic fluid at some point, usually in their third trimester. When this occurs, doctors will keep a special watch on a woman’s pregnancy; if it occurs near the end of a pregnancy, labor will be induced.
- Gestational Diabetes:
Approximately five percent of expectant mothers in the United States develop this type of diabetes. It may not sound as though this condition affects many women, but it is common enough, and serious enough, that pregnant women routinely get glucose screenings between twenty-four and twenty-eight weeks to test for it. Most women keep their blood sugar levels under control by diet and exercise. However, poorly controlled diabetes can result in serious consequences for the baby. Therefore, if a woman develops gestational diabetes, she will be closely monitored by her healthcare provider. Mothers who have gestational diabetes have a twenty-five to fifty percent chance of developing type two diabetes later in life. This risk can be significantly reduced by maintaining a healthy weight and lifestyle.
- Ectopic Pregnancy:
When a fertilized egg implants anywhere outside the uterus, it is called an ectopic pregnancy. The egg may implant in a fallopian tube, an ovary, the cervix, the abdomen, or in a c-section scar. There is no possible way to transplant an ectopic pregnancy into the uterus, so terminating the pregnancy is the only option. It is important to detect this type of pregnancy early because the growing embryo could rupture the fallopian tube. One in every fifty pregnancies has been reported as ectopic.
- Placenta Previa:
If a woman has a placenta previa, her placenta is lying unusually low in her uterus, next to or covering the cervix. This occurs in about one in two hundred pregnancies. Usually, placenta previa is not a problem during early pregnancy However, if it persists into later pregnancy, it can cause bleeding which may lead to a premature delivery or other complications. The location of the placenta can be checked during mid-pregnancy via ultrasound, but only about ten percent of women who have placenta previa at that point still have it by delivery. Mothers who have placenta previa during delivery are forced to deliver by c-section. 
- Chronic Hypertension
Chronic hypertension, or high blood pressure, is when a woman’s blood pressure is elevated prior to pregnancy. Pregnancy-induced hypertension, however, is when a woman’s blood pressure is elevated only during pregnancy. About eight percent of pregnancies result in pregnancy-induced hypertension, and it usually develops at the twenty week point. Generally, pregnancy-induced hypertension occurs close to a woman’s due date and will resolve itself after the delivery of the baby.
One of the most common pregnancy complications is pregnancy-induced anemia. This occurs when there is an insufficient amount of blood cells circulating in the mother’s blood. Mild cases of anemia during pregnancy shouldn’t harm the baby. There are two common types of anemia during pregnancy. The first is called dilutional anemia and is an increase of circulating blood, sometimes up to forty or fifty percent, in order to sustain the growing baby. The second type of anemia during pregnancy is iron deficiency anemia. This is when a woman’s iron level is insufficient and red blood cells aren’t being made in great enough quantities. Anemia during pregnancy can be treated either by taking supplements, eating foods rich in iron, or by administering of an IV of injectable iron supplement.
Pre-eclampsia is a syndrome that occurs only during pregnancy and is characterized by high blood pressure, protein in the urine, and swelling in the legs and feet. Approximately six to eight percent of pregnant women experience this pregnancy complication; close to ninety percent of those are first-time mothers. Many women are not even aware that they are suffering from pre-eclampsia until they are so told by their healthcare provider after having their blood pressure taken. Some symptoms of pre-eclampsia are: persistent headaches, seeing flashing lights, blurred vision, seeing spots, upper abdominal pain, and sudden excessive lower leg swelling. Since the cause of pre-eclampsia is currently unknown, accurate treatment for it remains a mystery. Most healthcare providers agree that birth is the only solution. If a woman is nearing her due date and is suffering from pre-eclampsia, her delivery may be induced.
Eclampsia during pregnancy is a very rare, but serious, complication which develops as a result of a pregnant woman having pre-eclampsia. Major symptoms of eclampsia are seizures and coma; therefore, diagnosing pre-eclampsia can be vital to prevent its more serious form. Eclampsia is considered a medical emergency. It can, however, be treated by giving the pregnant mother oxygen and drugs in order to prevent more seizures from occurring. In addition, urgent delivery of the baby is necessary to treat the pregnant mother properly.
Pregnancy lasts about forty weeks, counting from the first day of the last normal period. The weeks are grouped into three trimesters. The stages of pregnancy, when speaking about the mother, are referred to in trimesters. Likewise, when referring to the baby, the stages of pregnancy are addressed in weeks.
Weeks 1-12 First Trimester
During the first trimester, a woman’s body undergoes many changes. Hormonal changes that she experiences will affect almost every organ system in her body. These alterations in the way her systems function will produce symptoms even during the first weeks of pregnancy. A woman’s menstrual cycles stopping is a clear indication that she is pregnant. Other changes may include:
- Extreme tiredness
- Tender and swollen breasts
- Upset stomach, possibly including morning sickness
- Cravings or distaste for certain foods
- Mood Swings
- Frequent urination
- Weight gain or loss
Weeks 13–28 second trimester
Most women find the second trimester less trying than the first. They may notice their symptoms such as nausea and fatigue decreasing, but new, more noticeable changes will begin to occur. During the second trimester, a woman’s abdomen will begin to expand as the baby continues to grow. Before this trimester is over, she will begin feeling the baby move. As the baby grows, the mother may also experience:
- body aches in places such as the back, abdomen, groin, or thigh
- stretch marks on the abdomen, breasts, thighs, or buttocks
- darkening of the areola
- a line on the skin running from the belly button to the public hairline called the linea negra
- patches of skin darken, usually over the cheeks, forehead, nose, or upper lip; this is called the mask of pregnancy
- numb or tingling hands, called carpal tunnel syndrome
- itching on the abdomen, palms, and soles of feet (If these symptoms are accompanied by nausea, loss of appetite vomiting, jaundice, or fatigue they could be symptoms of a serious liver problem)
- swelling of the ankles, fingers, and face (If these symptoms progress to extreme swelling or sudden loss or gain of weight they could be signs of pre-eclampsia and a doctor should be contacted immediately)
Weeks 29–40 Third Trimester
During the third trimester, some of the discomforts from the second trimester will continue along with a few additional symptoms. At this time, many women find breathing normally difficult and begin to have to go the bathroom even more. These symptoms are as result of the baby getting larger and therefore putting more pressure on the mother’s organs. The manifestations of pregnancy will lessen after the delivery, but until then she be experiencing
- shortness of breath
- swelling of the ankles, fingers, and face (again, watch for other symptoms which may indicate pre-eclampsia)
- tender breasts which may leak colostrum, a watery pre-milk substance
- the belly button may protrude
- trouble sleeping
- the baby dropping, or moving lower in the abdomen
- contractions, which could be a sign of real or false labor
- the cervix begins effacing as the due date nears
- Main Article: Fetal development
Weeks 1-12 First Trimester
During the first four weeks the baby is approximately one twenty-fifth on an inch long. At this time, the baby’s:
- brain and spinal cord have begun to form
- heart begins to form
- arm and leg buds appear
At eight weeks the baby looks more like a human. It is about one inch long, weighs less than one eighth of an ounce, and its:
- major organs and external body structures have begun to form
- heart beats with a regular rhythm
- arms and legs grow longer, and the fingers and toes have begun to form
- organs begin to form
- eyes have moved forward on the face and eyelids have formed
- umbilical cord is clearly visible
At twelve weeks the baby is much longer, at about three inches long, and weighs almost an ounce. Also, the baby’s:
- nerves and muscles work together, the baby can make a fist
- external sex organs show whether it is a boy or a girl
- eyelids close to protect the developing eyes, they will not open again until the twenty-eighth week
Weeks 13–28 Second Trimester
At sixteen week, the baby reaches a length of about four to five inches and weighs almost three ounces. In addition their:
- muscle tissue and bone continue to form, creating a more complete skeleton
- skin begins to form, though it is nearly transparent
- mouth can make sucking motions
At twenty weeks, halfway through the pregnancy, the baby is about six inches long and weighs approximately nine ounces. Also, it:
- is more active, and the mother might begin feeling movement
- is covered in fine, downy hair called lanugo and a waxy coating called vernix which protects the baby’s skin forming underneath.
- has eyebrows, eyelashes, fingernails, and toenails
- can hear and swallow
At twenty-four weeks, the baby can store fat and has gained quite a bit of weight. It is approximately twelve inches long and weighs about one and a half pounds. Furthermore, their:
- bone marrow begins to make blood cells
- taste buds form on their tongue
- footprints and fingerprints have formed
- real hair begins to grow on their head
- lungs are formed, but do not work
- hand and startle reflex develop
- ability to sleep and wake regularly is in effect
- testicles begin to move from the abdomen into the scrotum, if a boy; if a girl, her uterus and ovaries are in place with a lifetime supply of eggs formed in the ovaries
Weeks 29–40 Third Trimester
At thirty-two weeks, the baby is gaining weight quickly, at about half a pound a week. The baby is now about fifteen to seventeen inches long and weighs about four to four and a half pounds. Also, the baby’s:
- bones are fully formed, but still soft
- kicks and jabs are forceful
- eyes can open and change and sense changes in light
- lungs are not fully formed, but practice “breathing” movements occur
- body begins to store vital minerals such as iron and calcium
- lanugo begins to fall off
At thirty-six weeks the baby reaches about sixteen to nineteen inches in length and weighs about six to six and a half pounds. Furthermore, the baby’s:
- vernix, protective waxy coating, gets thicker
- body fat gets bigger, leaving it less room to move around.
At weeks thirty-four to forty, the baby is ready to be born. By the end of thirty-seven weeks, the baby is considered full term and its organs are ready to function on their own. As the due date nears, the baby may assume a head-down position, for birth. At birth, the baby may weigh somewhere between six pounds, two ounces and nine pounds, two ounces; and be nineteen to twenty-one inches long. Most full-term babies gall within these ranges, but healthy babies come in many different sizes.
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