A high-risk pregnancy is one of greater risk to the mother or her fetus than an uncomplicated pregnancy. Pregnancy places additional physical and emotional stress on a woman’s body. Health problems that occur before a woman becomes pregnant or during pregnancy may also increase the likelihood for a high-risk pregnancy.
The factors that place a pregnancy at risk can be divided into four categories: existing health conditions, age, lifestyle factors, and conditions of pregnancy.
Existing Health Conditions
- High blood pressure. Even though high blood pressure can be risky for mother and fetus, many women with high blood pressure have healthy pregnancies and healthy children. Uncontrolled high blood pressure, however, can lead to damage to the mother’s kidneys and increases the risk for low birth weight or preeclampsia.
- Polycystic ovary syndrome. Polycystic (pronounced pah-lee-SIS-tik) ovary syndrome (PCOS) is a disorder that can interfere with a woman’s ability to get and stay pregnant. PCOS may result in higher rates of miscarriage (the spontaneous loss of the fetus before 20 weeks of pregnancy), gestational diabetes, preeclampsia, and premature delivery.
- Diabetes. It is important for women with diabetes to manage their blood sugar levels before getting pregnant. High blood sugar levels can cause birth defects during the first few weeks of pregnancy, often before women even know they are pregnant. Controlling blood sugar levels and taking a multivitamin with 40 micrograms of folic acid every day can help reduce this risk.
- Kidney disease. Women with kidney disease often have difficulty getting pregnant, and any pregnancy is at significant risk for miscarriage. Pregnant women with kidney disease require additional treatments, changes in diet and medication, and frequent visits to their health care provider.
- Autoimmune disease. Autoimmune diseases include conditions such as lupus and multiple sclerosis. Some autoimmune diseases can increase a women’s risk for problems during pregnancy. For example, lupus can increase the risk for preterm birth and stillbirth. Some women may find that their symptoms improve during pregnancy, while others experience flare ups and other challenges. Certain medications to treat autoimmune diseases may be harmful to the fetus as well.
- Thyroid disease. Uncontrolled thyroid disease, such as an overactive or underactive thyroid (small gland in the neck that makes hormones that regulate the heart rate and blood pressure) can cause problems for the fetus, such as heart failure, poor weight gain, and birth defects.
- Infertility. Several studies have found that women who take drugs that increase the chances of pregnancy are significantly more likely to have pregnancy complications than those who get pregnant without assistance. These complications often involve the placenta (the organ linking the fetus and the mother) and vaginal bleeding.
- Obesity. Obesity can make a pregnancy more difficult, increasing a woman’s chance of developing diabetes during pregnancy, which can contribute to difficult births.8 On the other hand, some women weigh too little for their own health and the health of their growing fetus. In 2009, the Institute of Medicine updated its recommendations on how much weight to gain during pregnancy.
- HIV/AIDS. HIV/AIDS damages cells of the immune system, making it difficult to fight infections and certain cancers. Women can pass the virus to their fetus during pregnancy; transmission also can occur during labor and giving birth or through breastfeeding. Fortunately, effective treatments exist to reduce the spread of HIV from the mother to her fetus, newborn, or infant.
- Teen pregnancy. Pregnant teens are more likely to develop high blood pressure and anemia (lack of healthy red blood cells), and go into labor earlier than women who are older. Teens also may be exposed to a sexually transmitted disease or infection that could affect their pregancy. Teens may be less likely to get prenatal care or to make ongoing appointments with health care providers during the pregnancy to evaluate risks, ensure they are staying healthy, and understand what medications and drugs they can use.
- First-time pregnancy after age 35. Older first-time mothers may have normal pregnancies, but research indicates that these women are at increased risk of having:
- A cesarean (pronounced si-ZAIR-ee-uhn) delivery (when the newborn is delivered through a surgical incision in the mother’s abdomen)
- Delivery complications, including excessive bleeding during labor
- Prolonged labor (lasting more than 20 hours)
- Labor that does not advance
- An infant with a genetic disorder, such as Down syndrome.
- Alcohol use. Alcohol consumed during pregnancy passes directly to the fetus through the umbilical cord. The Centers for Disease Control and Prevention recommend that women avoid alcoholic beverages during pregnancy or when they are trying to get pregnant. During pregnancy, women who drink are more likely to have a miscarriage or stillbirth. Other risks to the fetus include a higher chance of having birth defects and fetal alcohol spectrum disorder (FASD). FASD is the technical name for the group of fetal disorders that have been associated with drinking alcohol during pregnancy. It causes abnormal facial features, short stature and low body weight, hyperactivity disorder, intellectual disabilities, and vision or hearing problems.
- Cigarette smoking. Smoking during pregnancy puts the fetus at risk for preterm birth, certain birth defects, and sudden infant death syndrome (SIDS). Secondhand smoke also puts a woman and her developing fetus at increased risk for health problems.
Conditions of Pregnancy
- Having twins, triplets, or more. Pregnancy with twins, triplets, or more, referred to as a multiple gestation, increases the risk of infants being born prematurely (before 37 weeks of pregnancy). Having infants after age 30 and taking fertility drugs both have been associated with multiple births. Having three or more infants increases the chance that a woman will need to have the infants delivered by cesarean section. Twins and triplets are more likely to be smaller for their size than infants of singleton births. If infants of multiple gestation are born prematurely, they are more likely to have difficulty breathing.
- Gestational diabetes. Gestational diabetes, also known as gestational diabetes mellitus, GDM, or diabetes during pregnancy, is diabetes that first develops when a woman is pregnant. Many women can have healthy pregnancies if they manage their diabetes, following a diet and treatment plan from their health care provider. Uncontrolled gestational diabetes increases the risk for preterm labor and delivery, preeclampsia, and high blood pressure.
- Preeclampsia and eclampsia. Preeclampsia is a syndrome marked by a sudden increase in the blood pressure of a pregnant woman after the 20th week of pregnancy. It can affect the mother’s kidneys, liver, and brain. When left untreated, the condition can be fatal for the mother and/or the fetus and result in long-term health problems. Eclampsia is a more severe form of preeclampsia, marked by seizures and coma in the mother.
How many people are at risk of having a high-risk pregnancy?
The more risk factors a woman has, the more likely she and her fetus will be at risk during pregnancy and birth. Statistics are available for some risk factors:
- High blood pressure. According to statistics collected by the National Heart, Lung, and Blood Institute, about 6% to 8% of pregnant women in the United States have high blood pressure. About 70% of them are women who are pregnant for the first time.
- Preeclampsia. Preeclampsia affects an estimated 3% to 5% of pregnancies in the United States, and 5% to 10% of all pregnancies globally. The majority occur at term.
- Multiple births (twins). The National Center for Health Statistics reported that between 1980 and 2009, the twin birth rate increased 76%—from 19 to 33 per thousand births.3 For women between the ages of 35 and 39, twin births rose by 100%, and for women aged 40 and older, the increase in twin births was more than 200%. The increase in multiple births is due in part to the use of fertility treatments, especially in women older than age 35.
- Gestational diabetes. According to the Centers for Disease Control and Prevention (CDC), gestational diabetes affects 2% to 10% of pregnancies.
- Women between the ages of 40 and 44. The CDC also reported that the birth rate for women in their early forties increased to 10.2 births per 1,000 women in 2010, the highest rate since 1967. This increase is attributable at least in part to the expanded use of assisted reproduction (fertility treatments)
Good prenatal care will help to identify the potential for high-risk pregnancy. Health care providers will ask a woman about her medical history and will perform assessments to determine whether she is likely to experience a high-risk pregnancy based on her risk factors. Ongoing monitoring of physical health and personal habits will help a health care provider identify problems that develop during pregnancy.
A woman with a high-risk pregnancy will also likely receive care from a special team of health care providers throughout the pregnancy to ensure that she carries the fetus or fetuses to term.
Can a high-risk pregnancy be prevented?
Staying healthy is one of the best ways to lower the risk of having a difficult pregnancy. Many health care providers recommend that women who are thinking about becoming pregnant get evaluated to make sure they are in good preconception health. During pregnancy, there are also steps a woman can take to reduce the risk of certain problems1:
- Take at least 400 micrograms of folic acid (a type of vitamin B) every day before and during pregnancy.
- Get proper immunizations.
- Maintain a healthy weight; eat a good diet; get regular physical exercise; and avoid smoking, alcohol, or drug use.
- Start prenatal care appointments early during pregnancy and visit a health provider for regularly scheduled appointments throughout the pregnancy.
For women who are diagnosed with a high-risk pregnancy, treatment varies depending on the risk factors.
High Blood Pressure
Some changes to high blood pressure medication may be necessary during pregnancy. A health care provider can also offer advice about the best way to keep blood pressure under control. Suggestions may include recommendations to limit salt intake and get regular exercise.
Gestational diabetes, or developing diabetes during pregnancy, increases the risk of pregnancy complications. However, many women have healthy pregnancies and healthy infants because they follow a health care provider’s recommended diet and treatment plan. A woman diagnosed with gestational diabetes should1:
- Know her blood sugar level and keep it under control. A women diagnosed with gestational diabetes can track her own blood sugar levels by testing several times a day.
- Eat a healthy diet. A low carbohydrate diet with meals spread throughout the day helps to keep blood sugar under control. Health care providers will offer advice for developing a plan with the best diet for each individual.
- Keep a healthy weight. The amount of weight gain that is healthy for a woman will depend on how much she weighed before pregnancy. It is important to track both overall weight gain and the weekly rate of weight gain.
- Keep daily records of diet, physical activity, and glucose level. A woman with gestational diabetes should write down her blood sugar numbers, physical activity, and everything she eats and drinks in a daily record book.
Some women with gestational diabetes will also need to take medicine, such as an oral hypoglycemic tablet or insulin to help manage their diabetes.
HIV infection can be passed from a mother to her fetus as well as during childbirth and breastfeeding, but treatment can prevent transmission.
FAQs about High-Risk Pregnancy
1. How do I know if I have or will have a high-risk pregnancy?
If you are thinking about getting pregnant or are already pregnant, visit your health care provider. He or she will check your medical history and run tests to determine whether you are likely to have a high-risk pregnancy. Your health care provider will help you come up with a plan for reducing the risks while you are pregnant.
2. How can I best take care of myself and my fetus during my pregnancy?
You can take care of yourself and your fetus during pregnancy by eating healthy; avoiding drugs, smoking, and alcohol; exercising regularly; getting good prenatal care; and following your health care provider’s recommendations.
3. If I get gestational diabetes, will I still have diabetes after the infant is born?
If you develop diabetes during pregnancy, typically, you do not continue to have diabetes after delivery. However, gestational diabetes can raise a woman’s risk of developing diabetes later in life.
4. As an older first-time mom, am I more likely to have a cesarean section?
Just because a woman is older, it does not mean she will have a cesarean delivery. However, older woman are more likely to have high-risk pregnancies, so if you are an older first-time mom, it is possible that you will have complications that require a cesarean.
Reference: National Institutes of Child Health and Human Development