What is Diabetic Embryopathy?
Diabetes in mothers can negatively affect the development of the baby during pregnancy and lead to various birth defects. These issues, commonly called diabetic embryopathy, are 2-3 times more likely to occur in babies of diabetic mothers compared to those of non-diabetic mothers. High blood sugar in the mother can interfere with normal processes of the baby’s development and organ formation, although the exact reasons why this happens are unclear.
High blood sugar levels in the mother can disrupt both the mother’s and the baby’s metabolism. Both high levels of blood sugar and ketones (a type of compound produced when the body burns fat for energy) in the mother and the baby can contribute to these issues. Factors like diabetes in the mother and conditions inside the womb, as well as a predisposition in the baby’s genes, can all contribute negatively to the baby’s organ formation. Birth defects are likely to develop early in pregnancy, as this is when the baby’s organs are forming. If the mother’s metabolism is off balance, this increases the risk of the baby being born with birth defects.
Even when diabetic women manage their blood sugar levels well with insulin and a carefully controlled diet, their babies are still at a higher risk of birth defects and behavioral problems compared to babies of mothers without diabetes. The father being diabetic doesn’t increase the risk of birth defects in the baby. However, if the father has type 1 diabetes, this does increase the child’s chances of developing diabetes later in life. Children born to diabetic mothers may also have lower cognitive and motor development scores as they grow up.
What Causes Diabetic Embryopathy?
Gestational diabetes mellitus is a condition that arises due to a combination of environmental and genetic factors. This illness usually leads to high blood sugar levels, which can cause harm, followed by other side effects such as substances called ketones, fats known as triglycerides, and types of protein called branched-chain amino acids. Other by-products like lactate, pyruvate, and glycerol also contribute to harming the developing baby, but to a lesser degree.
High blood sugar can create a condition called oxidative stress and disrupt various chemical signals in the body, leading to complications in the placenta and depriving it of oxygen. This situation contributes to abnormal development in the unborn baby. Additionally, despite high levels of sugar in the blood, the substance responsible for transporting glucose called ‘GLUT1’ doesn’t decrease in the fetus during a specific part of the development process called neurulation.
This can lead to a high amount of sugar inside the cells. Around the 11th to 12th day, the baby’s developing neural tissue absorbs as much sugar as found in the mother’s blood. This could potentially cause severe defects in the nervous system of babies born to mothers with poorly managed diabetes during pregnancy.
Risk Factors and Frequency for Diabetic Embryopathy
Diabetes is more common in certain racial or ethnic groups, including Hispanic, African, Southeast Asian, and Native American communities. The number of people with diabetes is increasing in developed countries, which is linked to the worldwide obesity crisis. There’s also been an increase in the number of pregnancies affected by type 2 diabetes.
- Approximately 1.8% of pregnant women have either type 1 or type 2 diabetes before becoming pregnant.
- About 7.5% of pregnant women develop diabetes during pregnancy, known as gestational diabetes.
- Around 5 to 6% of pregnancies with gestational diabetes result in fetal anomalies.
This means there’s a high risk of complications related to diabetes in babies (diabetic embryopathy) in these pregnancies. As a result, healthcare professionals need to be particularly vigilant with these patients.
Signs and Symptoms of Diabetic Embryopathy
Getting a detailed history of both the patient and their mother is crucial when dealing with gestational diabetes. This includes the mother’s past medical conditions, medications, history of abnormal glucose tolerance, previous adverse pregnancy complications, and family history of diabetes. Babies born to mothers with poorly controlled gestational diabetes can have birth defects and other complications. However, it’s worth noting that there can be other factors contributing to these complications. As previously mentioned, mothers of advanced age, those from certain racial or ethnic groups, and those with a body mass index over 25 are all at a higher risk for developing gestational diabetes.
Immediately after birth, it’s important to physically examine the newborn to check for any birth defects. These babies are also at risk of having low blood sugar and may experience complications during delivery. The list of birth defects that may be present includes:
- Neural tube defects
- Craniofacial defects like cleft palate
- Baby having an unusually small head (microcephaly) or a small lower jaw (micrognathia)
- Brain defects, such as anencephaly or hydrocephaly
- Ear and eye abnormalities, such as microphthalmia and lens opacity
- Heart defects like tetralogy of Fallot and ventricular septal defect
- Spina bifida, a defect in the spine
Testing for Diabetic Embryopathy
Doctors need to be vigilant for signs of diabetes in pregnant women and regularly check the children of women who are at risk. This is done through regular glucose monitoring.
At 24-28 weeks of pregnancy, a glucose challenge test is done where the pregnant woman is given 50 grams of glucose. If her blood glucose level is more than 130-140 grams per deciliter an hour after consumption, this could be a sign of an issue. Women who don’t pass this test may have to take a longer, 3-hour glucose tolerance test.
Frequent check-ups, involving an ultrasound, allow doctors to see how the baby is developing. These ultrasounds help to confirm if the pregnancy is viable during the early phases, and then monitor the baby’s growth and overall wellness during the later stages. Around or before the 20th week of gestation, doctors can also identify any potential abnormalities with the fetus using the ultrasound.
Detection of certain specific conditions can be done with a Doppler ultrasound. This can identify issues such as fetal vasculitis, abnormalities in the placenta, and even complications with the fetal heart.
If there are suggestions of multiple defects or if the ultrasound isn’t clear due to reasons like obesity or amniotic fluid challenges, a Fetal Magnetic Resonance Imaging (MRI) might be considered. This can give a clearer view of the fetus and detect any potential congenital anomalies.
Between weeks 16-18, a test can assess if there’s a high level of a particular protein, alpha-fetoprotein, in the mother’s blood. This could suggest a risk of the baby developing neural tube defects, among other things.
Fetal lung maturity is assessed after 32 weeks. This analysis is done on the amniotic fluid to measure phosphatidylglycerol levels and the ratio of lecithin to sphingomyelin, which are both essential for the baby’s lung development.
After 32 weeks, additional check-ups that include non-stress tests twice a week, and contraction stress tests if necessary, are done. The aim is to keep a close eye on the development of the baby and the mother’s health.
Treatment Options for Diabetic Embryopathy
Monitoring high-risk groups before they become pregnant can help reduce the likelihood of birth defects. One of the best ways to achieve this is by ensuring that blood sugar levels are well managed and by following a particular diet before becoming pregnant. General advice for all women includes trying to keep HBA1c blood sugar levels below 6.1% and aiming for a body mass index of less than 25 before getting pregnant. Research has shown that taking folic acid supplements (5mg/day) even before getting pregnant can reduce the chances of birth defects associated with the brain and spinal cord.
For those who have high levels of hemoglobin A1c, it’s advised to seek advice before trying to conceive. The aim is to get blood sugar levels to a normal range before pregnancy, which can help prevent birth defects since organs start to develop early into the pregnancy, often before women may even know they’re pregnant.
Key actions to maintain healthy blood sugar levels include lifestyle changes, a balanced diet, and regular light exercise. Exercise can enhance overall well-being by reducing both resting and after-meal high blood sugar levels, as well as overcoming insulin resistance by reducing fat cell numbers. It’s also beneficial to cut down on carbohydrate intake and strive to maintain normal sugar levels to prevent ketosis and high blood sugar. Calorie intake guidelines suggest 30 calories per kilogram of body weight for women with a normal body mass index, 24 calories/kg for overweight women, and around 12-15 calories/kg for obese women.
It’s important to pay attention to how different carbohydrate-rich foods can influence blood sugar levels as some can have diverse effects despite their similar carbohydrate content. Diets with a low glycemic index can help reduce the risk of having a large baby at birth. Diets rich in fiber and with a low glycemic index can also limit the need for insulin. Several studies have also identified vitamin D’s positive effects on insulin sensitivity and insulin secretion.
Inositols, found in foods such as cereals, maize, legumes, and meat, can improve fetal organ formation and growth, as high blood sugar levels can have negative effects on inositol regulation and function. Inositol supplements have also been found to be beneficial for gestational diabetes.
Fish oil, rich in omega-3, helps to enhance insulin sensitivity and decrease inflammatory responses in the body.
Insulin is sometimes administered to women with gestational diabetes if a diet intervention does not work, as reducing harm to the fetus is a priority. Use of the oral drug metformin is considered safe for treating gestational diabetes, and antioxidants like vitamin C, vitamin E, and beta carotene can also theoretically help to prevent malformations by counteracting oxidative stress.
Ultrasound can keep track of the fetus in the first trimester, with further MRI imaging and fetal echocardiograms enhancing the understanding of any present anomalies. As part of follow-up visits, plans for delivery, expected complications, and emotional support for the mother should all be taken into consideration.
What else can Diabetic Embryopathy be?
Diabetic embryopathy, a condition that causes developmental issues in a baby due to high blood sugar levels in a pregnant woman, can look like several other disorders that cause similar problems.
Neural Tube Defects (NTDs) are one example. These are birth defects that stem from an issue with the early development of the brain and spinal cord in a baby. These defects can be caused by a range of factors, including diabetes, but are primarily caused by a deficiency in folic acid. Other things that can cause NTDs are a lack of vitamin B12 and certain genetic disorders.
Another similar condition is DiGeorge Syndrome. This disorder can cause heart abnormalities, facial differences, and learning difficulties. These symptoms can seem a lot like the complications of diabetic embryopathy.
VACTERL is a condition defined by a combination of defects. These include difficulties with the spine and anus, heart defects, a connection between the windpipe and esophagus, kidney issues, and deformities in the limbs. If a pregnant woman had diabetes, this could help distinguish VACTERL from diabetic embryopathy.
Then there’s CHARGE Syndrome, which involves multiple parts of the body. This disorder is characterized by eye defects (coloboma), heart issues, narrow or blocked nasal passages (atresia choanae), delayed growth, abnormal genitals, and unusual ears.
What to expect with Diabetic Embryopathy
The diet of a mother during her pregnancy has a significant impact on the outcome of the pregnancy. An evaluation before conception considering the mother’s risk factors and her blood glucose levels can be a great help in predicting future concerns. The best way to prevent or reduce the likelihood of birth defects is to keep blood sugar levels under tight control.
Additionally, the rate of deaths around the time of birth in pregnancies complicated by diabetes is 2.5 to 9 times higher than non-diabetic pregnancies. Several studies showed that type 2 diabetes tends to be linked with a higher rate of these deaths when compared to type 1 diabetes. This is often due to type 2 diabetes being associated with more risk factors such as high blood pressure, advanced age, obesity, bearing many children, etc. However, some studies from France have shown that stillbirths are more frequent in type 1 diabetes.
Possible Complications When Diagnosed with Diabetic Embryopathy
Women with diabetes who have higher than normal HBA1c levels are at a 22% risk of complications during pregnancy. These complications can occur if high glucose levels are experienced after 32 weeks of pregnancy and can cause the baby to have a larger than normal birth weight, increased red blood cell count, and low blood sugar. Possible complications can also include birth defects affecting many different organs, although they mainly impact the brain and heart. Approximately 8-12% of all pregnancies in diabetic women result in birth defects.
In the baby’s brain, these complications can include various defects such as water on the brain, absence of a large part of the brain and skull, and other complications. These may result in mental or cognitive impairment in the long term.
In terms of the baby’s heart, complications can include the transposition of major blood vessels with or without a hole in the wall of the heart, underdevelopment of the left side of the heart, holes in the walls of the heart chambers, thickening of the heart muscle, narrowing of the major artery from the heart, and other conditions.
Babies of diabetic mothers have a higher risk of dying before, during, or shortly after birth compared to babies of non-diabetic mothers. Death before birth (stillbirth) accounts for 44 to 84% of these deaths. Due to early diagnostics and management, this death rate has been reduced. Premature and early labor is also common, increasing the risk of complications in the newborn period.
Complications can also manifest as birth defects affecting numerous other organ systems. One rare disorder is the oculoauriculovertebral spectrum, a condition affecting the development of the face, ears, eyes, and spine. Other complications can include underdeveloped thigh bones, absence of a kidney, growth delays, and larger than normal birth weight.
Children born to diabetic mothers also have long-term risks including a higher chance of developing metabolic syndrome, diabetes, or insulin resistance later in life. These children may also experience a difficulty in delivery due to a large birth weight, high red blood cell count, and yellowing of the skin and eyes due to hypoxia in the womb. Less common are other mineral deficiencies such as low levels of calcium and magnesium. Breathing difficulties due to decreased levels of a lung fluid in premature babies and low blood sugar due to an overly active insulin system in the mother, have also been reported in some cases.
Preventing Diabetic Embryopathy
Diabetes is becoming a major health issue worldwide. This increase is largely due to less active lifestyles and unhealthy eating habits. Even though fortifying food has brought positive changes to our diet, a lack of self-care and decreased physical activity have significantly contributed to the rise in obesity and related health issues.
Educating people about their health and increasing awareness is more important for preventing obesity and diabetes than just using medications. People should be motivated to engage in more physical activity and to eat fresh, balanced meals.
It’s very important that high-risk individuals closely monitor their blood sugar levels before attempting to conceive. Mothers who already have diabetes need to understand the risks high blood sugar levels might pose on their baby’s development. Meanwhile, mothers without previous diabetes can still experience high blood sugar levels during pregnancy, which is known as gestational diabetes. Pregnancies affected by diabetes require regular check-ups to ensure the baby’s health.
