Chapter 1 Maternal fetal health
1.1 Antenatal fetal surveillance
Antenatal fetal surveillance, also known as antepartum fetal surveillance or fetal monitoring, refers to the various methods and techniques used to assess the well-being and health of a fetus during pregnancy. The goal of antenatal fetal surveillance is to identify any potential issues or complications that may arise, allowing for timely intervention and management to optimize the health outcomes for both the mother and the baby.
There are several common methods of antenatal fetal surveillance:
Ultrasound: Ultrasound scans are used to visualize the fetus in the womb. They can provide information about fetal growth, development, and overall well-being. Ultrasounds can also detect abnormalities or structural problems in the fetus.
Doppler Flow Studies: Doppler ultrasound is used to assess blood flow in the umbilical cord and fetal vessels. Changes in blood flow patterns may indicate problems such as fetal distress or placental insufficiency.
Fetal Heart Rate Monitoring: This can be done using electronic fetal monitoring (EFM) or handheld Doppler devices. Monitoring the fetal heart rate can provide valuable information about the baby’s well-being and response to stress.
Biophysical Profile (BPP): This is a combination of ultrasound and fetal heart rate monitoring to assess various fetal parameters such as fetal movements, muscle tone, breathing movements, amniotic fluid volume, and fetal heart rate reactivity.
Non-Stress Test (NST): This test measures the fetal heart rate in response to the baby’s movements. A reactive NST indicates a healthy fetus, while a non-reactive NST may necessitate further evaluation.
Contraction Stress Test (CST): This test evaluates the fetal heart rate response to uterine contractions, which helps assess the baby’s ability to tolerate the stress of labor.
Antenatal fetal surveillance is typically performed routinely during the third trimester of pregnancy, especially in high-risk pregnancies or when there are concerns about fetal well-being. It is an essential aspect of prenatal care, allowing healthcare providers to monitor the progress of the pregnancy and intervene if necessary to ensure the best possible outcome for both mother and baby.
Ref (Rouse 2021)
1.2 Prenatal diagnosis of fetal condition
Prenatal diagnosis refers to the various methods and techniques used to detect and assess fetal conditions or abnormalities before birth. These diagnoses are crucial for identifying potential health issues early in pregnancy, allowing for appropriate management and intervention to optimize outcomes for both the fetus and the mother.
Methods of Prenatal Diagnosis:
- Ultrasound Imaging:
- Visualize the fetus in the womb.
- Assess its growth, development, and overall health.
- Detect structural abnormalities such as heart defects, neural tube defects, and skeletal malformations.
- Provide information about fetal movements, amniotic fluid levels, and placental function.
- Genetic Testing:
- Identify genetic conditions or chromosomal abnormalities in the fetus.
- Techniques include amniocentesis, chorionic villus sampling (CVS), or non-invasive prenatal testing (NIPT).
- Screen for conditions like Down syndrome, cystic fibrosis, or neural tube defects.
- Prenatal Screening Tests:
- Assess the risk of certain fetal conditions or chromosomal abnormalities.
- Include maternal serum screening and cell-free DNA screening.
- Cannot provide a definitive diagnosis but help identify pregnancies at increased risk.
Importance of Prenatal Diagnosis:
Prenatal diagnosis plays a crucial role in identifying fetal conditions early in pregnancy, allowing for appropriate medical management, counseling, and decision-making for expectant parents. It empowers healthcare providers and families to take proactive steps to ensure the best possible outcome for the baby and prepare for any potential challenges that may arise during pregnancy or childbirth.
1.3 Maternal health conditions affecting the baby
1.3.1 Pre-eclampsia, Eclampsia and Hypertension
| Condition | Definition/Description |
|---|---|
| Gestational Hypertention | High BP in previously normotensive patient at ≥20 weeks of gestation without any of Preeclampsia features |
| Preeclampsia (PreE) | Gestational hypertension plus one or more of the following |
| - Proteinuria | |
| - Acute kidney injury (such as creatinine ≥90 mmol/L or 1 mg/dL) | |
| - Liver involvement (eg, elevated transaminases such as ALT or AST >40 IU/L) with or without right upper quadrant or epigastric abdominal pain) | |
| - Pulmonary edema | |
| - Uteroplacental dysfunction (eg, placental abruption, angiogenic imbalance, fetal growth restriction, abnormal umbilical artery Doppler waveform analysis, or fetal death) | |
| - Hematological complications (eg, platelet count <150 000/microL, disseminated intravascular coagulation, hemolysis) | |
| - Neurological complications (eg, altered mental status, blindness, stroke, clonus, severe headaches, or persistent visual scotomata) | |
| HELPP Syndrome | - PreE with hemolysis, elevated liver enzymes, and thrombocytopenia |
| Eclampsia | - PreE with Tonic-clonic seizure in a patient with preeclampsia in the absence of other neurologic conditions that could account for the seizure. |
1.3.2 Diabetes
| Diabetes Type | Definition | Effects on Fetus and Newborn |
|---|---|---|
| Gestational Diabetes (GDM) | Diabetes that develops during pregnancy, typically around the 24th to 28th week, due to insulin resistance and inadequate insulin secretion. | - Increased risk of fetal macrosomia (large birth weight). |
| - Higher likelihood of birth trauma during delivery. | ||
| - Increased risk of hypoglycemia and respiratory distress in the newborn. | ||
| - Higher chance of developing type 2 diabetes later in life. | ||
| Type 1 Diabetes | Autoimmune condition where the body’s immune system attacks the insulin-producing beta cells in the pancreas, resulting in little to no insulin production. | - Risk of fetal malformations and organ development issues if blood sugar levels are not well-controlled during pregnancy. |
| - Increased risk of stillbirth and miscarriage. | ||
| - Higher likelihood of preterm birth. | ||
| - Risk of hypoglycemia and respiratory distress syndrome in the newborn. | ||
| Type 2 Diabetes | Metabolic disorder characterized by insulin resistance and relative insulin deficiency, often associated with obesity and sedentary lifestyle. | - Higher risk of fetal macrosomia and birth complications due to maternal obesity and insulin resistance. |
| - Increased likelihood of preterm birth and fetal respiratory distress syndrome. | ||
| - Risk of neonatal hypoglycemia and metabolic abnormalities. | ||
| - Elevated risk of childhood obesity and later development of type 2 diabetes in the offspring. |
1.3.3 Maternal thyroid disorders
Maternal thyroid conditions encompass a range of disorders affecting the thyroid gland in pregnant individuals. These conditions can have significant implications for fetal development and maternal health. Understanding their impact is crucial for proper management and optimizing outcomes for both mother and baby.
Types of Maternal Thyroid Conditions:
- Hypothyroidism:
- Characterized by insufficient production of thyroid hormones.
- May result from autoimmune thyroiditis (Hashimoto’s disease), iodine deficiency, or other causes.
- Untreated hypothyroidism during pregnancy can lead to complications such as preeclampsia, preterm birth, low birth weight, and impaired neurodevelopment in the fetus.
- Hyperthyroidism:
- Characterized by excessive production of thyroid hormones.
- Often caused by Graves’ disease or toxic nodular goiter.
- Untreated hyperthyroidism can increase the risk of miscarriage, preterm birth, intrauterine growth restriction, and neonatal thyrotoxicosis in the fetus.
Effects of Maternal Thyroid Conditions on the Fetus:
- Neurodevelopmental Effects:
- Thyroid hormones play a crucial role in fetal brain development.
- Maternal hypothyroidism or hyperthyroidism can lead to cognitive impairment, intellectual disability, and behavioral problems in the offspring.
- Growth and Developmental Abnormalities:
- Thyroid dysfunction during pregnancy can affect fetal growth and development.
- Hypothyroidism may result in intrauterine growth restriction and low birth weight.
- Hyperthyroidism can lead to accelerated fetal growth and macrosomia.
- Cardiovascular Complications:
- Maternal thyroid disorders are associated with cardiovascular complications in the fetus.
- Hypothyroidism increases the risk of congenital heart defects, while hyperthyroidism may lead to fetal tachycardia and heart failure.
Management of Maternal Thyroid Conditions During Pregnancy:
- Monitoring and Treatment:
- Regular monitoring of thyroid function is essential throughout pregnancy.
- Treatment may involve thyroid hormone replacement therapy for hypothyroidism or anti-thyroid medications for hyperthyroidism.
- Close collaboration between obstetricians, endocrinologists, and other healthcare providers is crucial for optimal management.
- Risk Reduction Strategies:
- Maintaining adequate maternal thyroid hormone levels can help reduce the risk of adverse pregnancy outcomes.
- Women with thyroid conditions should receive preconception counseling and ongoing prenatal care to ensure proper management and monitoring.
Conclusion:
Maternal thyroid conditions can have significant implications for fetal health and development. Proper management, including monitoring thyroid function and timely intervention, is essential to mitigate risks and optimize outcomes for both mother and baby.