Yvonne decides to have a child before opting for the cervical conization surgery. At Dr. Trent’s suggestion, she has already begun taking prenatal vitamins, and with the assistance of an over-the-counter ovulation predictor kit, she is able to closely approximate the days of the month when she is most fertile and likely to conceive.

After the second month of trying to conceive, Yvonne’s home pregnancy test shows a positive result. With deep feelings of anxiety and elation at the thought of carrying a baby, Yvonne calls Dr. Trent’s office to schedule an appointment. The urine test conducted in his office confirms the results of the home pregnancy test.

Dr. Trent, with calendar in hand, tells Yvonne, “Your estimated due date is March 7^th. I want you to continue to take the prenatal vitamins once daily for the extra iron and folic acid you need, and add four glasses of milk or milk equivalents daily. Second,” he continues, “moderate caffeine is okay, but no smoking or drinking alcohol. Continue your normal exercise routines, but listen to your body in terms of fatigue or nausea. Third, at about 14 weeks gestation, we’ll schedule routine blood work to screen for spina bifida and Down syndrome. Then, between weeks 24 and 28, we’ll do the routine screen for gestational diabetes using an oral glucose tolerance test. Now, I know that neither you nor anyone in your family has a history of genetic conditions or diabetes, but such screening is routine.

“Finally, Yvonne, I would like you to schedule prenatal appointments with me once every four weeks. Also, as with all my expectant mothers, schedule an appointment with Dr. Costa at 20 weeks for a fetal medicine survey. Dr. Jean Costa is a top fetal medicine specialist. She will analyze the condition of the baby’s major body organs and alert me of any abnormalities at the midpoint of prenatal development.”

Yvonne leaves the doctor’s office that day with her next appointment scheduled in four weeks. That time passes by uneventfully, except for the morning sickness during the whole first trimester that actually occurs anytime, day or night. She tries to make good food choices, and understands that gaining some weight during her pregnancy is natural. In fact, as she learns from Dr. Trent, the Institute of Medicine recommends that for women like Yvonne, who was of normal weight before her pregnancy, total pregnancy weight gain should be 25–35 pounds.

It is a Tuesday morning when Yvonne, now 20 weeks pregnant, has her planned ultrasound performed at the office of the fetal medicine specialist. Gloria, the ultrasound technician, asks Yvonne if she wishes to have the sex of the unborn child determined. “Absolutely,” Yvonne replies emphatically.

Gloria begins the imaging procedure, and Yvonne sees a clear picture showing the body image, four heart chambers, blood in circulation, and individual body organs of the fetus.

“It’s a girl!” Gloria exclaims. Yvonne is delighted. Gloria then captures several sonogram images of the unborn child for Yvonne and for Dr. Costa’s examination.

Dr. Costa begins her consultation with Yvonne on a somber note. “Yvonne, unfortunately, I have some bad news; there is a problem with the baby’s kidney. There is an abnormal accumulation of urine in one kidney, a condition called hydronephrosis. This situation could be an indication of a more severe and widespread genetic disorder, or it could be limited to a birth defect of a single organ.”

“How can we be sure if it is limited to the kidney?” Yvonne manages to ask.

Dr. Costa responds, “I want to do amniocentesis in order to determine the extent of the abnormality. Although the procedure poses some risk—about one percent of miscarriages are related to the procedure—I would recommend it so that we can better understand the fetal anomaly.”

Yvonne agrees to the amniocentesis, but is in utter shock. The words “genetic disorder,” “hydronephrosis,” and “fetal anomaly” echo in her head as she waits for Dr. Costa to finish the day’s patients and perform the procedure.

Within an hour or so, it is underway. Yvonne sees the needle penetrate her abdomen, and watches on the sonogram screen as the needle enters the amniotic sac. In a matter of minutes, it is over and she is again seated in the doctor’s consultation chair. Dr. Costa explains that Yvonne needs to go home and rest for the remainder of the day. When Yvonne returns for her appointment next week, Dr. Costa will have the results of the genetic testing.

Over the next several days, Yvonne thinks about the results of the genetic tests and her options. The joy of knowing she is having a little girl is shadowed by the range of possibilities in her case: from all being well with her baby, to the child needing some sort of corrective surgery, to severe developmental problems.

Questions

1. What is the range of normal gestation for humans? What are the current guidelines for good prenatal care beyond those mentioned here? For example, why do pregnant women need extra calcium, iron, and folic acid?
2. In cases of severe morning sickness, are prescription medicines advised? If so, what is the mechanism of action of these drug(s)?
3. What hormone(s) in the urine do over-the-counter ovulation predictor kits, fertility monitors, and early pregnancy tests (EPTs) measure? How soon after conception can EPTs be performed?
4. How does ultrasound technology allow image capture of the fetus in utero? When is an ultrasound performed during pregnancy? When is an amniocentesis warranted and how is it analyzed?
5. Up to 5% of all pregnant women are diagnosed with gestational diabetes, and women who have had gestational diabetes have an increased risk of developing Type 2 diabetes later on in life. Distinguish between gestational diabetes and Type 2 diabetes in terms of cause, management, and consequences/outcomes.

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