There are two types of prenatal populations:

The Normal Pregnancy

What to Expect in the First Trimester in Normal Pregnancy

    Until the completion of the first twelve weeks of pregnancy, known as the first trimester, there are the general medical considerations. But this is also the time when miscarriage is most likely and up to 20% of diagnosed pregnancies end up miscarrying due to genetic mishaps at conception.

    Assuming all is well and normal and in every way unsuspicious, you can expect your normal pregnancy to involve monthly visits that will continue usually until the end of your second trimester (24 weeks). On your initial visit, you can expect that a careful history will be obtained or updated, depending on whether you are a new patient or not. Prior records from your last doctor or from consultants (like infertility specialists) who have been caring for you will be sent for. If there's a history of pre-existing conditions-hypertension, irritable bowel disease, diabetes, thyroid, etc., this will mean you're out of the "normal" pregnancy group.

    The initial physical exam will be used to assess your general maternal health, and you should expect routine blood work, vaginal cultures, and a check of the size of your uterus. If it's too early to hear your baby's heartbeat, then you should also expect the exam to give some indication as to whether there is someone growing inside your uterus making it the size expected for the gestational age.

    Routine blood work will check for anemia, immunity to Rubella, blood type, and diseases such as syphilis, hepatitis, and exposure to HIV, the virus that causes AIDS. Routine cultures will be for chlamydia, gonorrhea, and perhaps group B strep, although the strep culture is usually done later around 28 weeks. And you should expect a Pap smear, because no prenatal care is adequate without one.

    An initial ultrasound might be done during the first trimester to document a normal-appearing fetus, establish any agreement or disagreement with the patient's due date based on a last menstrual period, and to begin the actual bonding process. (Seeing your child for the first time is a moving experience!) Except for a change in the due date, which is just arithmetic, any other ultrasound surprises (like twins, for instance) will also be your ticket out of the "normal" pregnancy group.

    Many obstetricians feel comfortable getting two ultrasounds before 20 weeks, because the accuracy of the dating of the pregnancy falls off dramatically in later pregnancy. But because most babies grow at about the same rate before 20 weeks, this window is a good one in which to compare a particular baby with what's considered normal. The first ultrasound is often obtained before twelve weeks. The second one, if that is the usual practice of your doctor, will be obtained at least a month later so that an expected and appropriate interval-growth can be documented. The use of ultrasound is a financially controversial matter. Insurance companies will point to studies that indicate that routine use of ultrasound will not change the pregnancy outcomes of the general population.

But of course we're not talking about the general population--we're talking about you. Enjoy a doctor who likes ultrasound.

    Since the First Trimester is the highest risk miscarriage zone, any bleeding will prompt ultrasounds more often, sometimes even weekly. You'll be out of the normal group for this as well, and you should then expect serial blood levels of the pregnancy hormone, hCG, to watch for ensuing miscarriage, ectopic pregnancy, or resolution toward a normal pregnancy.

    Fetal heart tones are difficult to hear during the first trimester, so hearing the heartbeat will have to wait until the second trimester.

    So in summary, the First Trimester is important for assessing any history that may prove prophetic for the rest of your pregnancy, watching the weight of the mother and the growth of the fetus, and being alert to miscarriage scares.

What to Expect in the Second Trimester in Normal Pregnancy

    You can expect fundal height and fetal heart tones to be recorded each visit, and you can expect the visit intervals to range from anywhere between every two to four weeks, depending on your doctor. Of course the blood pressure, weight, and urine surveillance continues as well. The second trimester is normally a quiet time when the generalities of maternal and fetal health and appropriate fetal growth are observed. There are many self-help books on pregnancy, but each visit offers you a chance to add a perspective to the things you are reading. A free exchange of questions and answers addresses those things important to you as a prospective mother, and a care giver's particular communicative skills will determine the quality of your education as it pertains to your particular pregnancy.

    Between 15 and 20 weeks, you should expect to be offered an alphafetoprotein test to screen for neural tube defects (like spina bifida) and Down's syndrome. If you're over 35, you will be offered an amniocentesis for genetic studies, but being over 35 you're already considered high risk. (Other genetic studies are available at 10 weeks, like Chorionic Villous Sampling.)

    New and strange pains will come and go during this time as your growing baby begins to compete for available space. The baby will win, of course, so shortness of breath, ligament pains, nerve tinglings, and other weird effects occur around this time. You should expect your doctor to use the Second Trimester to look for signs of preterm labor or, if there's a history of preterm deliveries, incompetent cervix. Fetal movement, a sign of fetal well-being, usually happens around eighteen weeks. Called "quickening," the movements become more organized over time, and an obstetrician will be wary of any reports of decreased movement. Problems with movement or appropriate growth will prompt additional ultrasound studies to exonerate the health of your pregnancy.

What to Expect in the Third Trimester in Normal Pregnancy

    In the office, you should expect the interval between your visits to get shorter, depending on any special considerations being addressed. For the "perfect" pregnancy, every two to three weeks is the norm for weeks 24-36 weeks, then weekly after that. At some point near your due date, a physician or nurse will begin checking your cervix to look for change, that predictor for how imminent labor is. The time of checking depends on the practice. Some don't start until after the due date, some as soon as 37 weeks. Philosophical discussions regarding elective induction should be had between you and your doctor at this time, because if there are no obstetrical or medical indications for induction, elective induction should be done only at or after 39 weeks--and you should expect it to be your call. (And the cervix should be inducible.)

    No perfect pregnancy goes past the due date. Even though two weeks past the due date is considered the time to act no matter what, extra surveillance should begin after the due date. This is because your baby keeps growing but the placenta may start dying, and your baby's needs may outpace the placenta's ability to deliver. Non-stress tests and additional ultrasound may be prudent at this time.

    The Third Trimester is the time most likely to see pregnancy-related complications of Pregnancy-Induced Hypertension*, ("PIH," formerly pre-eclampsia or toxemia), so signs of this are of the utmost importance. Gestational diabetes is screened for at or around 26 weeks. Group B strep cultures are obtained at around 28 weeks.

    Then your baby's born and everyone lives happily ever after ...in the perfect pregnancy, that is.

• Bleeding (threatened miscarriage)
• Chronic hypertension
• Diabetes
• Asthma
• History of previous miscarriage, congenital abnormalities, stillbirth, or neonatal death
• Multiple gestation
• Medication exposure (either necessary medication for a pre-existing medical condition or exposure to medicines before a patient knew she was pregnant)
• Thyroid disease
• Smoking
• Alcohol or drug abuse
• Abnormal Pap smear

• All of the 1st trimester concerns, and...
• Incompetent cervix, increasing the risk of pre-term delivery
• Bleeding (due to placental abruption or previa)
• IUGR (Intra-uterine growth restriction-a baby small for the corresponding gestational age
• Gestational diabetes
• Pregnancy-induced hypertension (gestational hypertension)
• Sporadic or non-compliant prenatal care
• Pre-term labor
• Kidney infection
• Premature rupture of membranes (or leaking)
• Abdominal tenderness of the uterus (possible infection of the pregnancy)

 

• All of the 1st and 2nd trimester concerns, and...
• Decreased fetal movement
• Abnormal amount of amniotic fluid (too much = polyhydramnios; too little = oligohydramnios)
• Emotional abnormalities (pregnancy is a stress that may bring out borderline psychiatric conditions)
• Nausea and/or vomiting-this can't be looked at as the typical morning sickness of the First Trimester. This late in pregnancy, liver problems may be the cause, from a sneaky PIH variant called HELLP which would prompt immediate delivery to a more benign gallbladder problem which can be addressed after delivery.
• Right upper quadrant pain-same as  above.
• Decreased "reactivity" on non-stress test-in which the baby's heart rate does not accelerate after movement, which is the expected norm.
• Abnormal positioning of the baby (breech, transverse, etc.)

 

• Initial prenatal visit
• History or history update
• Thorough physical exam
• Documentation of pregnancy and estimation of due date (gestational age)
• Arrangement for initial blood work
• Standard cultures for gonorrhea, chlamydia.
• Pap smear, unless one had been recently done already.
• Listen for fetal heart tones if initial visit is over 12-13 weeks gestation.
• Possibly arrange an ultrasound.
• Arrange for perinatal consultation for risk factors, including age > 35.
• Request for old records if pertinent.
• Subsequent visits every 3-4 weeks
• Documentation of blood pressure, weight, urine tests for protein and glucose.
• Questions and answers to specific concerns.
• Reconciliation of ultrasound to gestation age.

• Visits every 3-4 weeks
• Much like the routine visits of the first trimester, except with the addition of listening for fetal heart tones.
• Between 15 and 20 weeks, offering of alphafetoprotein screen (Triple screen).
• Determination of fetal growth by serial fundal height determination.
• Beginning prenatal classes at the hospital or by private instruction.
• Cervical cerclage optimal time is 14 weeks if threat of incompetent cervix.
• The second trimester is the best trimester in which to have any necessary surgery-gall bladder, etc.

• 24 - 30 weeks--Visits every 2 - 3 weeks 
• At around 26 weeks--Glucola screen for gestational diabetes.
• At around 28 weeks--Attention to signs of preterm labor and institute monitoring if indicated
• 32 weeks--This is the time a baby usually "locks into" position. A breech baby at this time is a concern and warrants ultrasound.
• 36 weeks--

Group B strep culture.
Begin weekly visits or even more frequently if high risk.
Offer version of an abnormal position (breech) to normal position ("vertex"-head first.)
Possilby repeat routine blood work

• 37 - 38 weeks--Possibly begin weekly cervical checks.
• 39 weeks--Offer induction if cervix is ripe and prospective parents are desirous. 
• 40 weeks (term)--Begin post dates surveillance-more frequent visits, offering induction if cervix is ripe. 
• 41 - 42 weeks--Post-dates surveillance.
• 42 weeks--Probable induction. 

Although most doctors differ somewhat as to which point indicates mandatory delivery, 42 weeks seems to be a dividing line where waiting begins unacceptable risks.