Pregestational diabetes, or preexisting diabetes, refers to a condition in which a person has diabetes (typically type 1 or type 2 diabetes) before becoming pregnant.
Although pregnancies typically come with some risks, risks of complications for the pregnant person and fetus are higher in those living with type 1 (T1DM) or type 2 diabetes (T2DM).
This article explores pregestational diabetes in more detail, including how it differs from gestational diabetes, risks, and treatment options.
Pregestational diabetes is a form of diabetes mellitus that exists in a person before they become pregnant. Unlike gestational diabetes, which develops during pregnancy and typically resolves after childbirth, pregestational diabetes is a preexisting condition that requires ongoing management.
The primary types of diabetes that a healthcare professional can classify as pregestational diabetes are T1DM and T2DM.
In 1949, doctor Priscilla White developed the
However, it is important to note that the research to develop the classification system largely focused on people with T1DM rather than T2DM.
The classifications are as follows:
| Class | Age of onset (years) | Duration (years) | Vascular disease |
| B | over 20 | under 10 | none |
| C | 10–19 | 10–19 | none |
| D | before 10 | over 20 | benign retinopathy |
| F | any | any | nephropathy |
| R | any | any | proliferative (increasing) retinopathy |
| H | any | any | heart |
Pregestational diabetes and gestational diabetes are two different conditions. The latter
| Diabetes type | Timing of onset | Causes | Management |
| gestational | during pregnancy | insulin resistance and impaired glucose metabolism during pregnancy | diet, exercise, and, in some cases, medication |
| T1DM | before pregnancy | autoimmune reaction destroying the insulin-producing cells within the pancreas | insulin, monitoring blood sugar, monitoring carbohydrates, exercise |
| T2DM | before pregnancy | lifestyle factors and genes | oral medication and, in some cases, insulin, diet, and exercise |
Pregestational diabetes can increase the risk of complications for both the pregnant person and fetus. These can include:
- pregnancy loss before 20 weeks of gestation
- preeclampsia
- congenital anomalies
- higher-than-average birth weight
- neonatal hypoglycemia
By
- getting regular checkups and discussing pregnancy with a healthcare professional
- having regular eye exams
- managing blood glucose
- quitting smoking, if applicable
- stopping or changing certain prescription medications, such as cholesterol or hypertension drugs, under a doctor’s direction
- taking prenatal vitamins
- visiting an obstetrician or other specialist doctor
People with T1DM
For those living with T2DM,
Most commonly, a doctor will prescribe metformin, but in some cases, they may recommend insulin as the most appropriate treatment option.
Other tips to help manage diabetes during pregnancy include:
- attending all prenatal care checkups
- following a healthcare professional’s guidance on managing blood sugar
- taking insulin as directed by a healthcare professional
- discussing other medications with a healthcare professional
- discussing taking low dose aspirin with a healthcare professional, specifically whether it may help prevent preeclampsia
- considering working with a dietician
- discussing the likelihood of needing a cesarean section (C-section)
Managing pregestational diabetes before and during pregnancy is important for the well-being of both the pregnant person and the fetus. In the period before becoming pregnant, some steps a person can take to monitor their well-being
- keeping blood glucose as close to their recommended target range as possible
- getting regular checkups
- following diabetes treatment plans
- being physically active as advised by a healthcare professional
- taking diabetes medicines exactly as prescribed, if applicable
- stopping smoking, if applicable
- taking vitamins if advised to do so by a healthcare professional
Pregestational or preexisting diabetes refers to when a person has diabetes before pregnancy. This differs from gestational diabetes as it occurs before pregnancy and does not resolve after pregnancy.
Pregestational diabetes requires ongoing management during pregnancy to reduce risks for both the pregnant person and fetus. Managing pregestational diabetes involves careful monitoring of blood sugar levels, a balanced dietary plan, regular physical activity, and, in some cases, medications.
With guidance from healthcare professionals, individuals with pregestational diabetes can have typical pregnancies and give birth to healthy babies.