Overview
Fetal macrosomia refers to a condition where a newborn baby is much larger than average, weighing more than 8 pounds, 13 ounces (4,000 grams) at birth, regardless of gestational age. This can increase the risks associated with vaginal delivery and put the baby at risk of injuries during birth. It may also lead to health problems after birth. Fetal macrosomia can be challenging to detect and diagnose during pregnancy and may be associated with maternal age, diabetes, obesity, or excessive weight gain during pregnancy.
Understanding the disease
Symptoms
The symptoms of fetal macrosomia may include difficulty detecting and diagnosing during pregnancy, labor problems, genital tract lacerations, bleeding after delivery, and maternal age being a risk factor. Fetal macrosomia can also result from maternal diabetes, obesity, or weight gain during pregnancy. If a rare medical condition is suspected, healthcare providers may recommend prenatal diagnostic tests and a visit with a genetic counselor.
Risk Factors
Maternal age older than 35, maternal diabetes, obesity, weight gain during pregnancy, a history of fetal macrosomia, and having a boy are some risk factors for developing fetal macrosomia. Additionally, excessive weight gain during pregnancy, previous pregnancies, and overdue pregnancy can increase the risk.
Development
Fetal macrosomia develops when a baby in the womb grows to be much larger than average, typically weighing more than 8 pounds, 13 ounces (4,000 grams) at birth. The causes of fetal macrosomia can be attributed to genetic factors, maternal conditions such as obesity or diabetes, or rare medical conditions that affect fetal growth. In some cases, the cause remains unknown. Maternal diabetes, whether pre-gestational or gestational, can increase the risk of fetal macrosomia, as poorly controlled diabetes can lead to larger shoulders and greater body fat in the baby. A history of fetal macrosomia or being born weighing more than 8 pounds, 13 ounces is also a risk factor. Genetic and rare medical conditions can contribute to fetal macrosomia. In cases where risk factors are not present, a baby might have a rare medical condition that affects fetal growth. Prenatal diagnostic tests and consultation with a genetic counselor may be recommended in such cases. Overall, fetal macrosomia can result from a combination of genetic, maternal, and other factors. It's essential to consult with your healthcare provider if you have concerns about your baby's growth during pregnancy.
Assessment and Diagnosis
Triage
If fetal macrosomia is suspected, you should consult your healthcare provider. They may recommend prenatal diagnostic tests and possibly a visit with a genetic counselor, depending on the test results. Early detection and monitoring of fetal macrosomia can help manage potential risks and complications for both the mother and the baby during pregnancy and childbirth.
Diagnosis
Fetal macrosomia cannot be diagnosed until after the baby is born and weighed. However, if you have risk factors for fetal macrosomia, your healthcare provider will likely use tests to monitor your baby's health and development while you're pregnant, such as ultrasound. Toward the end of your third trimester, your healthcare provider or another member of your healthcare team might do an ultrasound to take measurements of parts of your baby's body, such as the head, abdomen, and femur. Your healthcare provider will then use these measurements to estimate your baby's weight. However, the accuracy of ultrasound for predicting fetal macrosomia has been unreliable. In addition to ultrasound, your healthcare provider might perform antenatal testing such as a nonstress test or a fetal biophysical profile to monitor your baby's well-being. A nonstress test measures the baby's heart rate in response to their own movements. A fetal biophysical profile combines nonstress testing with ultrasound to monitor your baby's movement, tone, breathing, and volume of amniotic fluid. If your baby's excess growth is thought to be the result of a maternal condition, your healthcare provider might recommend antenatal testing, starting as early as week 32 of pregnancy. Note that macrosomia alone is not a reason for antenatal testing to monitor your baby's well-being. If your healthcare provider suspects fetal macrosomia, they may also recommend an elective C-section. It is essential to discuss the risks and benefits of an elective C-section with your healthcare provider. After your baby is born, they will likely be examined for signs of birth injuries, abnormally low blood sugar (hypoglycemia), and a blood disorder that affects the red blood cell count (polycythemia). They may need special care in the hospital's neonatal intensive care unit. Keep in mind that your baby might be at risk of childhood obesity and insulin resistance and should be monitored for these conditions during future checkups. It is crucial to consult your healthcare provider about what you can do to relieve stress and promote
Management and Treatment
Complications
Potential complications of fetal macrosomia include maternal risks such as uterine rupture, bleeding after delivery, and genital tract lacerations. For the baby, possible complications may include lower than normal blood sugar levels, childhood obesity, and the need for operative vaginal delivery, forceps, or vacuum device during delivery. Fetal macrosomia is more likely to be a result of maternal diabetes, obesity, or weight gain during pregnancy, but in some cases, it may be due to a rare medical condition affecting fetal growth.
Prevention
Fetal macrosomia is a condition where a newborn is significantly larger than average, typically weighing over 8 pounds, 13 ounces (4,000 grams). It can lead to complications during childbirth and increase the risk of health issues for the baby after birth. While fetal macrosomia may not be entirely preventable, promoting a healthy pregnancy through exercise and a low-glycemic diet can help reduce the risk. Additionally, managing maternal conditions like diabetes and obesity can also lower the risk of fetal macrosomia. Proper prenatal care and monitoring are essential for early detection and management of fetal macrosomia.
Treatment
Fetal macrosomia cannot be treated before birth as it is a condition diagnosed after the baby is born and weighed. However, if your healthcare provider identifies risk factors during pregnancy, they may use tests to monitor your baby's health and development, such as ultrasounds. After the baby is born, the healthcare team will assess the baby for signs of birth injuries, low blood sugar, and blood disorders. If necessary, the baby may require special care in the neonatal intensive care unit. It is essential to follow your healthcare provider's recommendations regarding prenatal care and delivery. If a C-section is recommended, discuss the risks and benefits with your healthcare provider. Post-delivery, the baby will need to be monitored for potential health issues, including hypoglycemia, polycythemia, childhood obesity, and insulin resistance. Parents may need to make adjustments to the baby's diet and activity levels to promote a healthy weight. Regarding your own health, if your healthcare provider is concerned about the possibility of diabetes, you may be tested for the condition. During future pregnancies, you will be closely monitored for signs and symptoms of gestational diabetes. To cope with anxiety and stress related to fetal macrosomia, consult your healthcare provider and consider reaching out to support groups for parents of babies diagnosed with this condition.
Preparing for medical consultation
To prepare for an appointment for fetal macrosomia, you can ask your healthcare provider the following questions:
- What is likely causing the condition?
- What kinds of tests do I need?
- What needs to be done now?
- Do I need to follow any restrictions?
- How will fetal macrosomia affect my baby?
- Will I need to have a C-section?
- Will my baby need tests or special care after he or she is born? Remember to discuss any concerns or anxieties you have about your pregnancy and your baby's health. Your healthcare provider can offer guidance and support to help you cope with the situation.