Hypoglycemic And Pregnancy: Symptoms, Causes & Treatments 2022
This article is reviewed by a team of registered dietitians and medical doctors with extensive, practical clinical and public health experience.
Pregnancy causes many changes to the body, including regulating and metabolizing glucose and its ability to use insulin. Hypoglycemia occurs when blood sugar drops too low in pregnant women with or without diabetes but occurring more often in diabetic women.
Diabetes is the most common cause of pregnancy-related hypoglycemia. So pregnant women who notice hypoglycemia signs should undergo a test for diabetes.
This article looks at hypoglycemia during pregnancy, including the causes, symptoms and remedies, and how it may affect the fetus.
What Is Considered Low Blood Sugar During Pregnancy
Hypoglycemia can occur during pregnancy when blood sugar levels drop below 70 mg/dl (3.9 mmol/l) in those without diabetes but more often in diabetic women. Hypoglycemic episodes mainly occur from an imbalance of food intake, exercise and insulin maladjustments.
Maintaining optimal blood sugar is essential during pregnancy, as excessive levels can lead to gestational diabetes and its associated problems. In turn, low blood sugar can cause hypoglycemia and, if persistent, can cause further complications for both mother and fetus.
Hypoglycemia in Pregnancy
Diabetes is one of many conditions that can cause hypoglycemia in pregnant women, but being diabetic increases the risk, particularly in those injecting insulin.
A study suggests that between 19 to 44 % of diabetic women experience hypoglycemia during pregnancy. Another revealed that pregnant women with diabetes are more likely to suffer a severe hypoglycemic attack at least once during pregnancy.
What Is Hypoglycemia
Hypoglycemia is a medical condition when blood sugar drops less than 70 mg/dl. Its severity depends on blood glucose level and the state of the patient.
According to the Standards of Medical Care in Diabetes by the American Diabetes Association (ADA), there are three levels of hypoglycemia:
- Mild hypoglycemia. Blood glucose below 70 mg/dl but is 54 mg/dl or above.
- Moderate hypoglycemia. Blood glucose below 54 mg/dl.
- Severe hypoglycemia. Blood glucose below 40 mg/dl and the patient is deteriorating mentally and physically.
Role of Insulin
Insulin is a hormone released into the bloodstream from pancreatic beta cells. Insulin lowers blood sugar by converting glucose into energy, which powers the brain and body. The uptake of glucose into cells to build muscles and tissues also lowers blood sugar.
During pregnancy, the placenta produces human placental lactogenwhich causes insulin resistance, so pregnant women may need up to three times as much insulin to prevent hyperglycemia or gestational diabetes. Hormonal changes in pregnant women can also block the action of insulin, resulting in insulin resistance and disrupting how glucose is regulated.
According to the ADA, insulin is the first choice for blood glucose management of all diabetic types during pregnancy. All type 1 diabetics require insulin, but as oral diabetic medications are generally insufficient to overcome insulin resistance during pregnancy, those with type 2 diabetes often also need insulin.
Insulin is deemed safe for the developing fetus. It does not cross the placenta, so pregnant women with diabetes are often prescribed insulin (even if different medications controlled blood sugar appropriately before pregnancy).
As a result, those with diabetes during pregnancy must carefully monitor and adjust insulin doses to avoid hyperglycemia and hypoglycemia complications.
Symptoms of Hypoglycemia
Hypoglycemic signs appear when blood sugar drops too low, causing the body to change mentally and physically. However, these symptoms disappear once blood sugar stabilizes again.
Early Hypoglycemic Signs
- Nausea and vomiting
- Trembling and shaking
- Heart palpitations
- Pale skin
Late Hypoglycemic Signs
- Confusion and poor coordination
- Nightmares and bad dreams
- Numbness in the mouth and tongue
- Seizures and convulsions
- Losing consciousness
Causes and Risk Factors of Hypoglycemia
During pregnancy, hypoglycemia primarily associates with diabetes and insulin control; however, other conditions, although rare, may result in low blood sugar in pregnant women, such as other medications, some critical illnesses, and hormone deficiencies.
Types of Hypoglycemia
- Postprandial or reactive hypoglycemia. This happens within a few hours after a meal when blood sugar drops, usually in response to excess insulin produced following a large carbohydrate-based meal. This occurs more often in those with diabetes but can also occur in those without.
- Fasting hypoglycemia. This happens when blood sugar drops dangerously low through an extended period without eating, such as between meals. This is more common in those with a medical condition other than diabetes.
Not eating enough food, not often enough, or skipping meals entirely affects blood sugar in the body. The fetus constantly uses maternal glucose, regardless of the amount of food consumed. Pregnant women should eat a healthy balanced diet with sufficient carbohydrates and wholemeal food to regulate glucose levels.
Increased exercise or physical activity lowers blood sugar as the body converts glucose to energy to fuel the body.
Pregnant women who have diabetes may need to adjust their insulin doses as excess insulin reduces too much blood sugar resulting in hypoglycemia.
- Having diabetes. Both high and low blood sugar can occur at different stages during pregnancy, depending on insulin and diabetic medication. Pregnant women must monitor and adjust insulin doses during pregnancy as insulin levels can fluctuate.
- First trimester. Hypoglycemia occurs more often during the first trimester when nausea and vomiting (morning sickness) also frequently occur. A study revealed pregnant women with type 1 diabetes experienced severe hypoglycaemia three times more often in the first trimester than before pregnancy.
- Conditions that lower appetite or food intake. Low blood sugar can occur as a result of vomiting episodes, eating disorders and malnourishment.
- Other medications. Although these are not usually recommended for pregnant use, some sulfa-based antibiotics, salicylates and antimalarials can lower blood sugar.
- Prior hypoglycemic attacks before pregnancy
A single hypoglycemic episode during pregnancy is unlikely to cause harm to the mother or the fetus, but persistent attacks may pose more significant problems.
Severe hypoglycemia can result in seizures, coma and even death in those with diabetes during pregnancy. Newborns may experience the same complications when born with hypoglycemia or develop it soon after birth.
Babies born from diabetic mothers may suffer from a condition called macrosomia, making them unusually large. These newborns need monitoring as their blood sugar levels may drop dangerously low and are at a higher risk of breathing problems.
Diagnosis of Hypoglycemia
Hypoglycemia may be diagnosed depending on symptoms and blood glucose readings.
Pregnant women suspected of hypoglycemia may need to take several readings a day, record them, or use a blood glucose meter.
A routine blood check (usually before meals and at bedtime) involves:
- Pricking a finger with a lancet.
- Applying a drop of blood onto a test strip.
- Using a blood glucose meter to determine blood glucose levels.
One low blood sugar reading does not indicate persistent hypoglycemia, but pregnant women should seek medical assistance if blood sugar drops below 70 mg/dl more than twice a week.
Remedies Treating Hypoglycemia
Treating symptoms in the early stages can reverse hypoglycemia avoiding complications.
According to the ADA, pregnant women should immediately follow these measures upon recognizing signs of hypoglycemia:
- Sit or lie down in a safe place if possible.
- Consume about 15 g of simple carbohydrates with high sugar content, such as fruit juice, half a can of regular soda (not diet), four glucose tablets, one tablespoon of sugar or honey, or one tube of instant glucose gel. Pregnant women with diabetes should keep these items with them at all times.
Retest if symptoms do not improve in 15 minutes, and repeat treatment above if blood sugar is still less than 70 mg/dl. Follow up with a small snack such as a half sandwich or cheese and a few crackers. If still no improvement, then seek medical attention immediately.
Glucagon Injection Kits
A glucagon injection kit can be used to treat severe hypoglycemia episodes when the patient is unable to treat themselves.
The kit contains a synthetic form of the hormone glucagon and a sterile syringe. Once injected, glucagon travels to the liver, stimulating it to release glucose into the blood, raising blood sugar levels.
Rescue hypoglycemic treatment in those who are having a seizure or are unconscious often involves using a glucagon injection kit.
- Although hypoglycemia can occur in pregnant women without diabetes, persistent attacks are rare. Hypoglycemia most often happens in diabetic women, particularly in those injecting insulin.
- Infrequent or mild hypoglycemic episodes do not pose a significant risk to the mother or fetus but may cause newborn complications such as breathing difficulties if left uncontrolled.
- Recognizing signs of hypoglycemia as soon as they appear is vital in preventing hypoglycemic episodes. Early treatment can prevent complications such as coma or even death.
- Maintaining optimal blood sugar is crucial to avoiding both hyperglycemia and hypoglycemia in pregnant women. This involves a combination of eating frequent well-balanced meals, exercising appropriately, monitoring blood glucose regularly and adjusting insulin doses as required.
+ 8 sources
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- Persson B, Hansson U. Hypoglycemia in pregnancy. Baillière’s Clinical Endocrinology and Metabolism. 1993;7(3):731-739. Available from: https://www.sciencedirect.com/science/article/abs/pii/S0950351X05802162?via%3Dihub
- Heller S, Damm P, Mersebach H et al. Hypoglycemia in type 1 diabetic pregnancy: role of preconception insulin aspart treatment in a randomised study. ADA Diabetes Care. 2010;33(3):473-477. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2827491/#B1
- Authors at American Diabetes Association (ADA). Blood sugar testing and control: hypoglycemia (low blood glucose). Available from: https://www.diabetes.org/healthy-living/medication-treatments/blood-glucose-testing-and-control/hypoglycemia
- Authors at American Diabetes Association (ADA). Glycemic targets: standards of medical care in diabetes – 2020. ADA Diabetes Care. 2020;43(1):66-76. Available from: https://pubmed.ncbi.nlm.nih.gov/31862749/
- Authors at American Diabetes Association (ADA). Gestational diabetes and a healthy baby? Available from: https://www.diabetes.org/diabetes/gestational-diabetes
- Authors at American Diabetes Association (ADA). Diabetes and pregnancy. Available from: https://www.diabetes.org/diabetes/newly-diagnosed/diabetes-and-pregnancy
- Nielsen LR, Pedersen-Bjergard U, Thorsteinsson B et al. Hypoglycemia in pregnant women with type 1 diabetes: predictors and role of metabolic control. ADA Diabetes Care. 2008;31(1):9-14. Available from: https://care.diabetesjournals.org/content/31/1/9
- Authors at American Diabetes Association (ADA). Gestational diabetes: how will this impact my baby? Available from: https://www.diabetes.org/diabetes/gestational-diabetes/how-will-this-impact-my-baby