High-Risk Pregnancy - Causes, Symptoms, Care (High-Risk Pregnancy)

Pregnancy is an important time for every mother. A high-risk pregnancy can occur in pregnant women and may lead to health complications for both the mother and the baby in the womb. Receiving antenatal care and seeing the doctor as scheduled, along with regularly observing changes and abnormalities in the body, can help mothers stay healthy during pregnancy and deliver their little one smoothly.

What is a high-risk pregnancy?

A high-risk pregnancy is any risk condition that affects the health of the mother and the baby in the womb during pregnancy, during delivery, and after delivery. It is dangerous and may be severe enough to cause death. Close care by a specialist physician is required to prevent severe outcomes. The older the pregnant mother is, the higher the risk becomes.

Screening for pregnant women

Screening for pregnant women can be done as follows:

1. Screening specifically for pregnant women at high risk refers to screening in pregnant women who are at high risk for developing certain conditions, such as screening for gestational diabetes, assessment for preterm labor, etc.
2. Screening for all pregnant women refers to testing all pregnant women regardless of whether the pregnancy is high-risk, such as checking the size and characteristics of red blood cells, ABO and Rh blood group testing, syphilis screening, hepatitis B virus testing, HIV testing, urinalysis for protein and glucose, etc. In Thailand, the number of thalassemia patients is high, so thalassemia screening should be performed in all pregnant women.

Characteristics of a high-risk pregnancy

• High-risk conditions from the mother include diabetes, high blood pressure, heart disease, kidney disease, sexually transmitted infections, obesity, or being overweight.
• High-risk conditions from the pregnancy include multiple pregnancy (twins), pregnancy at an age younger than 17 or older than 35, a history of miscarriage or preterm birth, and ectopic pregnancy.
• High-risk conditions from external factors include smoking, drinking alcohol, using illicit drugs, and consuming unhygienic food.

Symptoms of a high-risk pregnancy

• Abdominal pain that does not improve
• High fever
• Frequent and severe headaches
• Lightheadedness, dizziness, or fainting
• Chest pain, palpitations, difficulty breathing
• Severe fatigue
• Indigestion, tightness in the abdomen; abdominal size smaller or larger than normal
• The baby stops moving or moves less
• Nausea and vomiting worse than typical morning sickness
• Swelling, redness, or pain in the face or arms and legs
• Bleeding or vaginal discharge
• The baby has not started moving even at 5–6 months of pregnancy
• Wanting to harm yourself or the baby in the womb

Risk factors for a high-risk pregnancy

1. Maternal and health-related risk factors such as
   • Obesity
   • Thalassemia
   • Underlying diseases such as diabetes, high blood pressure, kidney disease, and heart disease, etc.
   • Maternal age during pregnancy that is too high or too low, such as pregnancy at an older age or pregnancy at younger than 18 years
2. Risk factors during pregnancy such as
   • Twin pregnancy
   • Severe morning sickness
   • Gestational diabetes
3. Risk factors from pregnancy history include
   • Multiple pregnancies
   • Previous miscarriage (2 or more miscarriages)
   • Previous preterm birth and post-term birth

Complications of a high-risk pregnancy

• Gestational diabetes caused by hormones or chemicals that inhibit insulin function. This increases the risk of preeclampsia, pregnancy-induced hypertension, preterm birth, fetal death in the womb, an excessively large baby leading to difficult delivery, increased risk of miscarriage, and congenital abnormalities. It may also cause hydramnios (excess amniotic fluid), increasing the risk of preterm birth and a higher chance of disability.
• Preterm birth is when the baby is delivered at a gestational age of less than 37 weeks. Organs are not yet fully functional, so the baby has a higher chance of death. It may be caused by abnormalities during pregnancy, such as preeclampsia, infection during pregnancy, chronic disease, etc. It can lead to complications in the baby such as infections in the bloodstream and respiratory system, respiratory distress with risk of chronic lung disease and lung infection, brain hemorrhage, retinal abnormalities, jaundice after birth, and intestinal dysfunction. Preterm birth also has a chance of recurring in subsequent pregnancies.
• High blood pressure in pregnant women is a condition in which a pregnant mother has blood pressure of 140/90 mmHg or higher. It can occur in women after 20 weeks of pregnancy and can be fatal. Although the cause is unclear, it is suspected to be due to abnormal placental development. Effects on the pregnant mother include seizures, brain hemorrhage, and placental abruption; without prompt treatment it may result in death. For the baby in the womb, blood supply from the placenta decreases, causing restricted growth, abnormalities, and possible fetal death. Concerningly, high blood pressure in pregnancy may recur and increase in subsequent pregnancies. In some cases, the doctor may recommend termination of pregnancy for safety.
• Preeclampsia is a severe complication in pregnant women at 20 weeks of gestation or more, in which blood supply to various organs is reduced. It is common in young, first-time pregnant women. Severity ranges from mild (blood pressure 140/90 mmHg). Symptoms of preeclampsia begin with moderate swelling without complications. In severe cases, blood pressure 160/110 mmHg, there may be severe headache, blurred vision, epigastric tightness, low platelet count; the most severe stage includes seizures, convulsions, and loss of consciousness after severe preeclampsia. Important complications for the mother include brain hemorrhage, placental abruption, neurological abnormalities, pneumonia, and pulmonary edema. The baby may become oxygen-deprived due to placental abruption and may result in death of both the mother and the baby in the womb.
• Fetal growth restriction is a condition in which the baby weighs less than normal and is small, with a high risk of death. It is often caused by placental insufficiency, maternal genetics, or infection during pregnancy, resulting in low oxygen and low blood sugar, abnormal body temperature, low immunity, and respiratory problems, increasing the risk of congenital abnormalities. If severe, it may lead to fetal death in the womb or during delivery.

Diagnosis of a high-risk pregnancy

1. Antenatal care history The doctor will take a detailed history to screen pregnant mothers who are in a high-risk group for close monitoring.
2. Measuring fundal height Using a measuring tape from the top of the uterus to above the pubic bone is a screening method for fetal growth restriction before confirmation with ultrasound.
3. Targeted Ultrasound High-resolution ultrasound is performed to assess fetal structure and development in detail to detect congenital abnormalities and to monitor fetal growth in high-risk pregnancies.
4. Cell-Free DNA Screening Genetic testing from maternal blood to assess risk of fetal chromosomal abnormalities such as Down syndrome (Trisomy 21), Edwards syndrome (Trisomy 18), Patau syndrome (Trisomy 13), including abnormalities of sex chromosomes (X and Y).
5. Amniocentesis and chorionic villus sampling Amniocentesis is performed in the second trimester and chorionic villus tissue sampling at 10–12 weeks of pregnancy for testing to screen for chromosomal abnormalities and genetic diseases such as anemia and thalassemia.
6. Cervical length measurement To assess the risk of preterm birth, especially in mothers at high risk or with abnormal symptoms.
7. Ultrasound to monitor fetal development and health Assess growth, movement, heart rate, amniotic fluid volume, fetal movements, and fetal position to ensure appropriate development at every gestational stage.
8. Laboratory tests To detect urinary tract infection, syphilis, and HIV.

Care and treatment for a high-risk pregnancy

• Receive antenatal care with an obstetrician-gynecologist to provide care, reduce maternal risk factors, and promote appropriate fetal growth.
• If you have an underlying disease while pregnant, you must strictly follow the doctor’s recommendations.
• Count fetal movements; there should be 10 or more movements within 12 hours each day.
• See the obstetrician-gynecologist at every scheduled appointment to monitor fetal growth and other symptoms during pregnancy, and to follow up and control existing underlying diseases.
• Regularly measure blood pressure at home.
• If the mother and baby are in a life-threatening condition, the doctor may recommend induction of labor or cesarean delivery.

Prevention of a high-risk pregnancy

• Before pregnancy, both the mother and father should undergo a detailed health check. If there are health problems, treatment or disease control should be done before planning pregnancy, such as controlling high blood pressure to normal levels, losing weight if overweight to reach standard range, etc.
• Take folic acid 2–3 months before pregnancy to prevent abnormalities in the baby, such as spina bifida.
• Once you know you are pregnant, begin antenatal care with an obstetrician-gynecologist immediately. Provide your personal and health history in detail so the doctor can plan care and treatment, and attend every appointment.
• During pregnancy, observe bodily changes at all times. If abnormalities occur, see a doctor immediately.

High-risk pregnancies that should see an MFM doctor

• Severe morning sickness, significant weight loss, unable to eat
• Vaginal bleeding
• Severe lower abdominal pain
• High fever
• Reduced fetal movement or no movement
• Water breaking; clear fluid leaking from the vagina; ruptured amniotic sac
• Swelling, epigastric tightness, blurred vision, severe headache
• Preterm labor before 37 weeks of gestation

Advantages of antenatal care with an MFM doctor

• Expert in caring for high-risk pregnancies especially for mothers who become pregnant at an older age; pregnant mothers with underlying diseases such as diabetes, high blood pressure, and heart disease; mothers with a history of preterm birth, miscarriage, or preeclampsia.
• Expert in using high-resolution ultrasound equipment to examine fetal structure and internal organs in detail and to assess blood flow in the placenta and umbilical cord.
• Expert in advanced genetic screening and diagnosis which may require additional tests such as amniocentesis, chorionic villus sampling, and fetal umbilical cord blood sampling.
• Expert in treating the fetus while still in the womb If abnormalities are detected, treatment plans or procedures for the baby can be made before birth, such as in cases of fetal hydrops or abnormal heart rhythm.