High-Risk Pregnancy | Find Specialists & Get Information

A high-risk pregnancy is one in which

• due to the expectant mother’s medical history (so-called anamnestic risks) or
• findings from examinations during the current pregnancy (pregnancy-related risks)

that increase the risk of complications compared to a “normal pregnancy.” The potential complications may affect the pregnancy itself or the delivery.

Pregnancies classified as high-risk therefore require more intensive care. The expectant mother then benefits from closer and more intensive medical care and monitoring during pregnancy and childbirth.

A high-risk pregnancy does not mean that there is an immediate danger to the mother and/or child. According to the definition of the Joint Federal Committee (GBA), approximately 75 percent of pregnancies involve pregnancy risks. These are recorded in the prenatal care record.

However, only 40 to 50 percent of pregnancies are classified as high-risk. At the same time, about 97 percent of children are born healthy.

In certain situations, high-risk pregnancies may be associated with a high-risk birth. This applies, for example, to the following conditions:

• Preterm birth,
• placenta previa (risk of bleeding or premature placental abruption),
• Any discrepancies between the baby’s size or position and the birth canal.

Through prenatal care, healthcare providers aim to identify high-risk pregnancies and high-risk deliveries as early as possible.

This begins with a consultation, known as a medical history. The doctor asks about

• past and current illnesses and symptoms,
• pregnancies and births, as well as
• medication use.

This is followed by various examinations. Based on these findings, the doctor can assess whether there may be an increased health risk during pregnancy or childbirth. The doctor then provides a risk assessment. This allows for the targeted planning of therapeutic and, in particular, preventive measures for individualized prenatal care.

In Germany, the Joint Federal Committee’s Maternity Guidelines govern this process. These guidelines regulate medical care for women with statutory health insurance during pregnancy and after childbirth. This includes, in particular, the scope and timing

• of preventive care services,
• diagnostic services, and
• therapeutic services.

These guidelines also specify the criteria for classifying a pregnancy as high-risk.

A pregnancy is classified as high-risk based on the medical history and a physical examination © Blue Planet Studio | AdobeStock

Factors such as

• age,
• current and past medical conditions,
• previous surgical procedures, as well as
• complications or specific circumstances during previous pregnancies and births

.

Chronic medical conditions

Conditions that may pose an increased risk to the mother and/or child include, for example:

• kidney disease,
• liver disease,
• diabetes mellitus,
• chronic inflammatory bowel diseases,
• severe obesity, and
• high blood pressure.

In most cases today, a chronic condition is no longer an obstacle to pregnancy. In the past, women with diabetes, epilepsy, or multiple sclerosis were advised to avoid pregnancy. Today, these conditions are no longer a reason to forego pregnancy.

Nevertheless, it is important to be aware of the health risks to both mother and child in order to ensure optimal care during pregnancy. A safe pregnancy is then ensured by

• appropriate medication management,
• additional prenatal appointments, or
• supplementary diagnostic tests.

Mother’s Age

Pregnant women who

• are having their first child at age 35 or older, or under age 18, or
• who are over 40 years old and become pregnant again,

are classified as having a high-risk pregnancy.

A woman’s fertility declines noticeably starting at age 30. At the same time, the likelihood of a chromosomal abnormality in the child increases significantly starting at age 35. However, most fetuses with chromosomal abnormalities have such severe conditions that they die in utero. For example, only about one in two children with trisomy 21 (Down syndrome) is viable.

Thus, the probability that a child with Down syndrome will be born alive

• 1 in 1,300 (0.08%) at age 25,
• at age 35, 1 in 365 (0.27%), and
• at age 45, 1 in 30 (3.3%).

In addition, older pregnant women have a higher risk of pregnancy-related complications. These include, for example, gestational diabetes or high blood pressure.

Father’s Age

The father’s age plays

• in the development of certain conditions in the child, as well as
• certain pregnancy risks

. According to a study by the University of Zurich, for example, very young fathers appear to contribute to an increased risk of Down syndrome.

According to a study by the University of Aarhus in Denmark, the risk of preterm birth is significantly higher among fathers over the age of 50.

Obstetric and Gynecological Risk Factors

In general, women who have given birth multiple times—with more than four children—face increased pregnancy risks. They have an increased risk of genetic defects and placental insufficiency. Placental insufficiency prevents the unborn child from receiving an adequate supply of oxygen and nutrients.

Due to potential mechanical risks during childbirth resulting from overexertion of the mother’s body, this leads to an increased risk of complications during delivery.

If complications have already occurred during previous pregnancies, the current pregnancy is also considered a high-risk pregnancy.

Specifically, this applies to the following circumstances:

• Multiple miscarriages or premature births
• Previous stillbirths or severely impaired children
• Previous births of infants weighing over 4,000 grams (known as macrosomia) or with underdevelopment (known as hypotrophy or growth retardation)
• Previous multiple pregnancies or births
• Complications during previous deliveries:
  • abnormal placental location (placenta previa),
  • premature placental abruption (abruptio placentae),
  • postpartum hemorrhage,
  • coagulation disorders,
  • convulsions, or
  • vascular occlusion caused by a blood clot (thromboembolism).

Gynecological risk factors include:

• fertility treatment,
• surgical procedures on the uterus, including
  • Cesarean section,
  • removal of a fibroid (a benign tumor of the uterine muscle) or due to a uterine malformation.

Certain health problems may not develop or become apparent until during pregnancy. Once the risk has been identified through an examination, the pregnancy is then classified as a high-risk pregnancy.

Hypertensive disorders of pregnancy

Pregnancy-induced hypertension is a major cause of

• illnesses and complications, as well as
• maternal and fetal mortality

during pregnancy. Pregnant women with elevated blood pressure are therefore classified as having high-risk pregnancies. Hypertensive disorders of pregnancy include, among others:

• Gestational hypertension: elevated blood pressure in the mother after the 20th week of pregnancy,
• Preeclampsia: high blood pressure accompanied by protein in the urine,
• Eclampsia: seizures occurring in the context of preeclampsia,
• HELLP syndrome: breakdown of red blood cells, elevated liver enzymes, and a low platelet count.

Blood Group Incompatibility

In some pregnancies, the mother and child have different blood types and Rh factors. The mother may then develop antibodies against the red blood cells, usually shortly before delivery.

In a subsequent pregnancy, these antibodies cause the mother’s immune system to react against the baby, which can result in harm to the baby.

Gynecological factors

The following situations are also considered to carry an increased risk for the further course of the pregnancy:

• Multiple pregnancies and abnormal fetal position in the uterus, e.g., transverse lie,
• bleeding from the uterus (uterine bleeding),
• threat of preterm birth due to premature contractions or cervical insufficiency, and
• exceeding the due date or uncertainty regarding the due date.

Additional risk factors

• Anemia: low hemoglobin levels (Hb levels),
• gestational diabetes.

Due to the increased risk for the expectant mother and the unborn child, high-risk pregnancies require more intensive prenatal care. Therefore, in the case of a high-risk pregnancy, checkups are scheduled more frequently:

• more frequently than every four weeks up to the 32nd week of pregnancy, and
• more frequently than every two weeks during the last 8 weeks of pregnancy.

In particularly critical cases, the pregnant woman may also be referred for inpatient monitoring during the final weeks. This often takes place at a hospital with perinatal care services. Such facilities specialize in providing medical care for pregnant women and fetuses shortly before and after birth.

In this context, the expectant mother decides which examinations or procedures she ultimately wishes to undergo. That is why a trusting relationship with the doctor is particularly important during pregnancy.

In high-risk pregnancies, additional tests may be necessary depending on the findings and medical history. These include the following tests.

Standard Ultrasound

A standard ultrasound examination is recommended in the following situations:

• In cases of recurrent uterine bleeding,
• in cases of complicated early pregnancy,
• during early pregnancy with an intrauterine device (IUD) in place,
• in cases of uterine enlargement due to multiple fibroids (uterus myomatosus) and cysts or solid tumors of the fallopian tubes or ovaries (adnexal tumors),
• to measure the cervix when cervical insufficiency is suspected,
• in cases of premature rupture of membranes and/or labor contractions,
• for monitoring the course of an existing fetal anomaly or disease,
• in cases of suspected placental abruption, as well as
• to monitor cases of complicated labor.

Advanced Ultrasound Examination

Using a high-resolution ultrasound machine, the organs can be examined in even greater detail. This examination is therefore called detailed diagnostic sonography. It can be used in the following situations:

• To monitor fetal growth when developmental abnormalities in the fetus are suspected,
• To monitor a multiple pregnancy,
• To assess placental location in cases of confirmed placenta previa (position of the placenta in front of the internal os),
• to monitor initial intrauterine bleeding, and
• in cases of suspected fetal malposition starting at the 36th week of pregnancy.

Doppler ultrasound

An examination of the blood vessels and blood flow using a special ultrasound device is performed, for example, in the following situations:

• When fetal growth restriction, diseases, or malformations are suspected,
• in cases of hypertensive disorders of pregnancy,
• to monitor the condition following fetal death or preeclampsia/eclampsia,
• in cases of abnormal fetal heart rate,
• in cases of uneven growth among multiple fetuses,
• in cases of suspected heart defects or heart disease.

Cardiotocography (Fetal Heart Rate and Contraction Monitor)

Cardiotocography (CTG) is the simultaneous recording of the fetal heart rate and uterine contractions. It is used for the early detection of fetal problems.

According to maternity care guidelines, a CTG should be performed

• be performed before the 28th week of pregnancy if there is a suspicion of premature labor or if labor is being inhibited by medication, or
• from the 28th week of pregnancy if fetal heart rate changes have been detected

.

Additional Tests

During an amniocentesis (amniotic fluid test), amniotic fluid is extracted using a cannula. The doctor inserts it through the skin into the amniotic sac.

The amniotic fluid is then tested, for example, for

• certain chromosomal abnormalities,
• inherited disorders, and several other conditions,
• infections,
• blood group incompatibility, and
• lung maturity in cases of threatened preterm birth

are examined. Amniocentesis should ideally be performed between the 14th and 19th weeks of pregnancy.

In contrast, chorionic villus sampling (CVS) can be performed as early as the 10th to 12th week of pregnancy. In chorionic villus sampling, a cannula is also inserted through the abdominal wall. However, the doctor does not puncture the amniotic sac. Instead, he or she simply removes a tissue sample from the chorionic villi.

This testing method can also be used to diagnose chromosomal abnormalities and certain genetic disorders.