The first prenatal examination should take place during the first six to eight weeks of pregnancy, or when a woman’s menstrual period is two to four weeks late. The first prenatal care appointment typically takes longer than the other checkups that follow. During this visit, the physician will try to gather as much information as possible about the medical and family histories of the patient and her partner. The patient should answer the physician’s questions honestly, even if they make her feel uncomfortable or embarrassed. Anything that a patient tells her physician is confidential, meaning that the physician cannot disclose information to a third party without permission.

During this visit, the patient will be asked to answer questions about her:

• pregnancy history (if applicable)
  
  
• Menstrual cycle (e.g., first day of last period)
  
  
• Contraceptive practices
  
  
• Use of over-the-counter or prescription medications
  
  
• Allergies, medical conditions and diseases (past and present)
  
  
• Past surgeries
  
  
• Lifestyle factors, including exercise habits, diet, alcohol consumption, tobacco use and recreational drug use
  
  
• Sexually transmitted disease (STD) risk factors (e.g., having multiple sex partners)
  
  
• Work environment
  
  
• Home environment

The patient’s answers to these questions and others will influence the care she receives. In addition, the patient will have the opportunity to ask the physician any questions she may have about the pregnancy. The patient may choose to compile a list of questions to ask the physician ahead of time and bring it with her to the appointment. This helps to ensure that important questions are not overlooked.

After the patient has answered all relevant questions, the physician will perform a physical examination. During the physical exam, the physician will check the woman’s height, weight and blood pressure, and assess her general health.

The physician will perform a pelvic examination and rectal exam. During a pelvic exam, the physician inserts a device called a speculum into the woman’s vagina. The speculum separates the vaginal walls and allows the physician to view the cervix (the opening of the uterus [womb]). The pelvic exam enables the physician to check for:

• Clues about the baby’s due date. To estimate the baby’s due date, most physicians add seven days to the first day of the patient’s last period, and then subtract three months. For instance, if the woman’s last period began on June 23, the estimated due date would be April 30 (June 23 + 7 = June 30 – 3 months = April 30). The majority of babies are born within two weeks of their predicted due date. Changes in the cervix and in the size of the uterus can also help the physician predict the baby’s due date. Determining the baby’s approximate due date in early pregnancy allows the physician to monitor the baby’s growth and interpret laboratory results as accurately as possible. In addition, knowing the baby’s due date affects how the physician might manage preterm labor, should it occur.
  
  
• Cervical abnormalities or infections. The physician will also perform a Pap smear. During this procedure, the speculum remains in place while the physician gently collects mucus and cells from the woman’s cervix. This screening procedure is used to detect cervical changes before cancer develops. The test also detects infection. Cervical infections, such as the STDs chlamydia and gonorrhea, can adversely impact a pregnancy and the health of the developing fetus.
  
  
• Size and position of the ovaries and uterus. To determine this information, the physician will remove the speculum and insert two gloved fingers into the patient’s vagina. This allows the physician to check the cervix. The physician will then place the other hand on top of the patient’s abdomen to check the size of the ovaries and uterus.
  
  Many physicians also evaluate the size and shape of the woman’s birth canal at this time. These determinations can help the physician predict whether the patient may experience problems during labor and delivery. For instance, the patient’s pelvis may not seem wide enough for the baby’s head to pass through or the pelvis arch may be narrow, resulting in problems in the labor process. Although it is difficult to make an accurate prediction this early in the patient’s pregnancy, the physician may make a note to re-evaluate this at a later date.
  
  

  

The physician will also take blood and urine samples during the initial prenatal care visit. Additional blood and urine tests may be done at later appointments as well.  

Routine first trimester lab tests include blood tests to screen for:

• Blood type (A, B, AB or O)
  
  
• Complete blood count (CBC)
  
  
• Rhesus factor (Rh negative or Rh positive)
  
  
• Red blood cell antibodies (typically Rh antibodies, which increase the baby’s risk of developing conditions such as anemia or jaundice following birth)
  
  
• Exposure to hepatitis B, chickenpox (varicella), measles, mumps or rubella
  
  
• HIV (optional)
  
  
• Syphilis, gonorrhea, chlamydia and other STDs 
  
  
• Toxoplasmosis (optional)
  
  
• Sickle cell trait or sickle cell disease (for women at high risk such as women of African or Mediterranean decent)
  
  
• Cystic fibrosis (optional)

First-trimester urine tests typically screen for:

• Bladder or kidney infection (both of which require treatment)
  
  
• Elevated blood sugar (which may indicate diabetes)
  
  
• Protein (which may indicate kidney disease)

After the exams and blood and urine tests, the physician will discuss general pregnancy guidelines and restrictions with the patient. If the patient or her partner is a potential carrier of a hereditary disease, genetic testing may be offered at this time. This might be offered as well to women who are older (over the age of 35) as they also are at a higher risk for genetic problems.

The remaining first-trimester prenatal care appointments will be briefer than the initial visit.  They will all include physical exams. Patients will rarely require another pelvic exam unless the physician discovers something unusual during the initial visit or if the patient reports certain types of symptoms. Ultrasound (sonogram) is often scheduled for the sixth or seventh week to confirm the pregnancy. At around 10 to 13 weeks, the physician may perform a chorionic villus sampling (CVS), in which a portion of the patient’s placenta is removed and analyzed to identify certain birth defects. This is typically done when women are over age 35 because there is an increased risk of chromosomal conditions, such as Down syndrome. CVS may also be performed if:

• A woman has given birth to a child with a birth defect in the past
  
  
• There is a family history of a particular genetic disorder
  
  
• There is an abnormal screening during the first trimester

In addition, a new and less invasive screening technique that may soon become standard prenatal testing is the integrated prenatal screening (IPS). The IPS test is performed in two stages. First, an ultrasound examination is done between the 11 and 13 weeks plus six days of pregnancy to measure the fluid accumulation behind the fetus’ neck (nuchal translucency). After the ultrasound exam, the physician will perform a blood test on the expectant mother to measure the level of a protein normally found in the blood of every pregnant woman, PAPP-A (pregnancy associated plasma protein-A). The second stage of IPS involves another blood test performed on the mother at 15 to 20 weeks of pregnancy, ideally at 15 to 16 weeks for the earliest possible results. The second blood test measures the levels of four proteins normally found in the blood of all pregnant women: AFP (alpha-fetoprotein), hCG (human chorionic gonadotropin), E3 (unconjugated estriol) and inhibin A. Results from the ultrasound and both blood tests are then integrated into a single analysis.

It should be noted that results from the IPS can only be obtained after the ultrasound AND both blood tests are completed (typically not before 17 weeks of gestation). However, IPS has a high-accuracy rate for detecting chromosomal abnormalities including Down syndrome and neural tube defects such as spina bifida, which can eliminate the need for more invasive testing like CVS. Patients interested in IPS should consult with their ObGyn to determine if they are good candidates for the test.