Diabetes in pregnancy – you cannot turn back time

Columnist discusses options for a pregnant woman with poorly controlled hyperglycemia.

Issue: February 2008

ByRonald Tamler, MD, PhD, MBA

Ronald Tamler

A 23-year-old Hispanic woman, diagnosed with type 1 diabetes at age 4, presented to our diabetes clinic. She had missed several follow-up appointments over the past six months and had a documented history of noncompliance and multiple admissions to the hospital for diabetic ketoacidosis.

The patient had missed her period two weeks before, after starting birth control with a vaginal contraceptive ring that month. An evaluation in the emergency department had demonstrated a random blood glucose level of 306 mg/dL and a positive human chorionic gonadotropin. She had a history of four elective abortions, sickle cell trait and asthma. The patient denied diabetic retinopathy, neuropathy or nephropathy. She almost never tested her blood glucose level, did not pay attention to food choices and did not count carbohydrates when eating. She had been prescribed glargine, 26 U at night, and aspart, 14 U with breakfast and 16 U with lunch and dinner.

Physical exam: She was in no acute physical distress, 5 feet, 2 inches tall, 154 lb, BP 110 mm Hg/60 mm Hg, heart rate 88 beats per minute; otherwise unremarkable. The patient had a job at a bakery and lived with her sister. Her boyfriend had persuaded her to have the previous two abortions.

The patient did not bring a glucose log or meter to the appointment and admitted to missing one to two doses of prandial insulin per day and two to three doses of glargine per week. Lab chemistry was normal, except for a glucose level of 286 mg/dL and HbA1c of 11.8%.

1. What are you going to tell this patient?

Her child will have a high risk of shoulder dystocia.

She should eat as many carbohydrates as possible to nourish the fetus.

Her child will have a significantly elevated risk of serious malformations, even if she manages to reduce her blood glucose levels to goal.

Her child will have a significantly elevated risk of serious malformations, but if she manages to achieve target glycemic control within the next trimester, it will be the same risk as for a pregnancy in a mother without diabetes.

Her child will certainly have macrosomia.

2. What is your first action?

You explain to the patient that an abortion is mandatory to preserve her own health and then walk her over to the Ob/Gyn department.

Since the patient is obviously not achieving target glycemia with aspart, you change her rapid-acting insulin to glulisine.

You calmly state that you cannot help her any further because she has been a no-show for more than three appointments and does not adhere to keeping records or taking her insulin.

You explain possible outcomes of this pregnancy. If the patient chooses to continue, you have the patient fitted with an insulin pump and lispro, overbook her for your clinical educator’s sessions to teach carbohydrate counting and refer her to ophthalmology.

You call her boyfriend at his work phone number and tell him to “come over and talk some sense” into the patient.

CASE DISCUSSION

Women with diabetes in pregnancy may represent the most challenging and yet the most rewarding group of patients we deal with in our field. This patient has long-standing, poorly controlled diabetes and a history of multiple abortions. Macrosomia (1E) and shoulder dystocia (1A) are complications seen with hyperglycemia later on in pregnancy. While they still might occur, they are not the primary concern in early pregnancy.

The human embryo undergoes rapid growth and differentiation during the first eight weeks of gestation and is most sensitive to noxious stimuli, such as alcohol, radiation or the effects of hyperglycemia. Even mildly elevated HbA1c levels in the first trimester are associated with an increased risk of miscarriage and severe malformations of the child. This risk increases to 50% for a HbA1c of 14%.

Due to the lag between fertilization and diagnosis of pregnancy, in this case four weeks, the damage may already have been done: The significant hyperglycemia has already wrought havoc (1C). It is therefore most prudent to recommend birth control to women with poorly controlled diabetes who may become pregnant and to strive for optimal glycemic control in a motivated patient before a planned pregnancy ensues.

Leaving the patient alone in this terrible quandary is a heartless choice (2C). She should be informed about the possible outcomes of a pregnancy and a referral to the obstetrician for further counseling should be considered.

However, in this case, the patient made the informed decision to continue her pregnancy. Although time has indeed been lost and certain irreversible injuries to the embryo may have occurred, achieving normoglycemia as rapidly as feasible over the remainder of the pregnancy offers the best option to limit the damage. Glargine and glulisine have a Class C rating for pregnancy, and if these were the only tools available for achieving normoglycemia, one might consider using them, particularly as new reports on the use of glargine in pregnancy emerge (2B). However, it appears safer to use lispro or aspart, which have a Class B rating, in an insulin pump.

This is exactly the approach we selected. A motivated patient returned a few days later to the clinic with a detailed glucose and food diary. She was started on insulin pump therapy and successfully trained to use the device. Initial settings based on her log were adjusted during daily phone calls, and the patient rapidly achieved blood glucose levels close to normoglycemia. She followed up every one to two weeks at our diabetes clinic, with titration of her insulin basal rates, insulin-carbohydrate ratios and correction factor. We also arranged for close ophthalmologic follow-up, as both pregnancy and rapid change in glycemic control may worsen diabetic eye disease.

This patient’s HbA1c improved from 11.8% to 9.2% within the first month of insulin pump therapy and then to 7.4% at 20 weeks. She remained committed to the hard work associated with tight glycemic control, despite losing her job and losing her home. She also remained committed to continuing the pregnancy, even after she was told at 20 weeks’ gestation that her child had a cardiac defect, Trisomy 21 and hydrops.

While this particular case illustrates the tragic side of what cannot be undone in early pregnancy, following a patient this closely can provide great satisfaction. In the future, we hope to tell happier stories of healthy infants, as the awareness of the deleterious effects of hyperglycemia in pregnancy and its treatment options increases.

Ronald Tamler, MD, PhD, MBA is an Instructor in the Division of Endocrinology at Mount Sinai School of Medicine.