Risks During Pregnancy 

Risks to Pregnancy

There are many external factors, including alcohol, drugs, smoke, high temperatures, radiation exposure, and high altitudes that can pose a serious threat to a developing fetus. Listed in the directory below, you will find information that covers some potential hazards, for which we have provided a brief overview.

Alcohol and Pregnancy

The risks involved with alcohol use during pregnancy:

Alcohol consumption by the mother is a leading cause of preventable birth defects in the fetus. Everything a mother drinks also goes to the fetus. Alcohol is broken down more slowly in the immature body of the fetus than in an adult's body. This can cause the alcohol levels to remain high and stay in the baby's body longer. In addition, the risk of miscarriage and stillbirth increases with alcohol consumption.

One major consequence of drinking alcohol during pregnancy is a serious condition called fetal alcohol syndrome (FAS). FAS is the leading cause of mental retardation. In addition, FAS is characterized by the following:

  • growth retardation in the fetus
  • facial defects
  • behavioral problems
  • eating and sleeping problems in the baby
  • sight and hearing problems
  • the need for medical care during the child's life
  • deformed organs
  • central nervous system dysfunction

A less severe, but still detrimental form of fetal alcohol syndrome is a condition called fetal alcohol effects (FAE). FAE is present in a larger population of newborns in the US and is characterized by some physical or mental defects that can be directly attributed to alcohol use during pregnancy.

The full picture of FAS usually occurs in babies born to alcoholic mothers, or those who drink more than four to five drinks/day. Even light or moderate drinking can affect the developing fetus. Because no amount of alcohol is safe, the US Surgeon General recommends that pregnant women avoid alcohol during pregnancy.

Smoking and Pregnancy

Did You Know?

Studies have shown that maternal smoking during pregnancy has long-term effects on children's behavior and health, including adolescent drug abuse and negative behavior and conduct such as impulsiveness, risk-taking, and rebelliousness. Prenatal exposure to smoke may also predispose children to early smoking experimentation.

Source: National Clearinghouse for Alcohol and Drug Information (NCADI)

The risks involved with smoking during pregnancy:

Although fewer women are smoking during their pregnancy now than ever before, the habit still persists among many women. In addition, even if a pregnant woman does not smoke, she may be exposed to secondhand smoke in the household, workplace, or in social settings.

Smoke can be damaging to a fetus in several ways, and may cause the following:

  • low birthweight
  • preterm birth
  • stillbirths
  • increased risk of birth defects

Subsequently, babies born to smokers may also have the following problems:

  • poor lung development
  • asthma and respiratory infections
  • increased risk of sudden infant death syndrome (SIDS)
  • physical growth deficiency
  • intellectual development deficiency
  • behavioral problems

The mother, too, may experience problems during her pregnancy as a result of smoking, including, but not limited to, the following:

  • placental complications
  • preterm labor
  • infections in the uterus

Researchers believe the effects of carbon monoxide (which reduces oxygen in the blood) and nicotine (which stimulates certain hormones) cause many of these adverse effects.

However, according to the US Food and Drug Administration (FDA), if a woman quits smoking early in her pregnancy, she increases her chance of delivering a healthy baby.

Did You Know?

Pregnant women who use drugs such as heroin, cocaine, marijuana, PCP, methadone, and/or amphetamines may give birth to drug-addicted babies.

Many of these babies experience withdrawal symptoms known as neonatal abstinence syndrome (NAS). Symptoms of NAS may include tremors; increased sensitivity to noise or other stimuli; feeding problems; poor coordination; and excessive crying and/or irritability.

Source: National Clearinghouse for Alcohol and Drug Information (NCADI)

Illegal Drug Use and Pregnancy

The risks involved with illegal drug use during pregnancy:

The effects of illegal drugs, such as cocaine, can be devastating on a fetus. Unfortunately, many women of childbearing age in the US use some form of illegal drug.

A mother taking illegal drugs during pregnancy increases her risk for anemia, blood and heart infections, skin infections, hepatitis, and other infectious diseases. She also is at greater risk for sexually transmitted diseases. Almost every drug passes from the mother's bloodstream through the placenta to the fetus. Illicit substances that cause drug dependence and addiction in the mother also cause the fetus to become addicted.

A laboratory test, called a chromatography, performed on a woman's urine can detect many illegal drugs, including marijuana and cocaine. Both marijuana and cocaine, as well as other illegal drugs, can cross the placenta. Marijuana use during pregnancy may be linked to behavioral problems in the baby. Cocaine use can lead to premature delivery of the fetus, premature detachment of the placenta, high blood pressure, stillbirth. Infants born to cocaine-using mothers may have an increased risk of sudden infant death syndrome (SIDS). The effects of cocaine on the fetus may include, but is not limited to, the following:

  • growth defects
  • intestinal abnormalities
  • hyperactivity
  • uncontrollable trembling
  • learning problems

Heroin and other opiates, including methadone, can cause significant withdrawal in the baby, with some symptoms lasting as long as four to six months. Seizures may also occur and are more likely in babies born to methadone users.

If a woman stops taking illegal drugs during her first trimester, she increases her chances of having a healthy baby.

Medications and Pregnancy

The risks involved with medication use during pregnancy:

When pregnant, a woman should always check with her physician before taking any prescription or over-the-counter medication. All medications affect the fetus differently, depending on the stage of development, the type and dosage of the medication being taken, and the drug tolerance of the mother-to-be.

Women who take medications for preexisting medical conditions, such as epilepsy or high blood pressure, should always check with their physician before continuing to use that medication while pregnant.

The US Food and Drug Administration (FDA) is reviewing its regulation of drugs for pregnant women. Unfortunately, there is little scientific information available about the effects of many medications on a pregnancy.

Always consult your physician before taking any medication during pregnancy.

Medical Conditions and Pregnancy

Medical conditions that may affect pregnancy:

Certain medical conditions may complicate a pregnancy. However, with proper medical care, most women can enjoy a healthy pregnancy, despite their medical challenges.

Diabetes before pregnancy:

Diabetes is a condition where sufficient amounts of insulin are either not produced or the body is unable to use the insulin that is produced. Insulin is the hormone that allows glucose to enter the cells of the body to provide fuel. When glucose cannot enter the cells, it builds up in the blood and the body's cells literally starve to death. Diabetes in pregnancy can have serious consequences for the mother and the growing fetus. The severity of problems often depends on the degree of the mother's diabetic disease, especially if she has vascular (blood vessel) complications and poor blood glucose control.

Diabetes that occurs in pregnancy is described as:

  • Gestational diabetes - when a mother who does not have diabetes develops a resistance to insulin because of the hormones of pregnancy. Women with gestational diabetes may be non-insulin dependent or insulin dependent.
  • Pre-existing diabetes - women who already have diabetes and become pregnant.

What is gestational diabetes?

Gestational diabetes is a condition in which the glucose level is elevated and other diabetic symptoms appear during pregnancy in a woman who has not previously been diagnosed with diabetes. In most cases, all diabetic symptoms disappear following delivery. However, women with gestational diabetes have an increased risk of developing diabetes later in life, especially if they were overweight before pregnancy.

Unlike other types diabetes, gestational diabetes is not caused by a lack of insulin, but by blocking effects of other hormones on the insulin that is produced, a condition referred to as insulin resistance.

What causes gestational diabetes?

Although the cause of gestational diabetes is not known, there are some theories as to why the condition occurs.

The placenta supplies a growing fetus with nutrients and water, as well as produces a variety of hormones to maintain the pregnancy. Some of these hormones (estrogen, cortisol, and human placental lactogen) can have a blocking effect on insulin, which usually begins about 20 to 24 weeks into the pregnancy.

As the placenta grows, more of these hormones are produced, and insulin resistance becomes greater. Normally, the pancreas is able to make additional insulin to overcome insulin resistance, but when the production of insulin is not enough to overcome the effect of the placental hormones, gestational diabetes results.

What are the risks factors associated with gestational diabetes?

Although any woman may develop gestational diabetes during pregnancy, some of the factors that may increase risk are:

  • family history of diabetes
  • obesity
  • having given birth previously to a very large infant, a still birth, or a child with a birth defect
  • age (women who are older than 25 are at greater risk than younger women)

Although increased glucose in the urine is often included in the list of risk factors, it is not believed to be a reliable indicator for gestational diabetes.

How is gestational diabetes diagnosed?

A glucose screening test is usually performed between 24 and 28 weeks of pregnancy, which involves drinking a glucose drink followed by measurement of the blood sugar level after one hour.

If this test shows an increased blood sugar level, a three hour glucose tolerance test may be performed after a few days of following a special diet. If results of the second test are in the abnormal range, gestational diabetes is diagnosed.

Treatment for gestational diabetes:

Specific treatment for gestational diabetes will be determined by your physician based on:

  • your age, overall health, and medical history
  • extent of the disease
  • your tolerance for specific medications, procedures, or therapies
  • expectations for the course of the disease
  • your opinion or preference

Treatment for gestational diabetes focuses on keeping blood glucose levels in the normal range. Treatment may include:

  • special diet
  • exercise
  • daily blood glucose monitoring
  • insulin injections

Possible gestational diabetes complications for the baby:

Unlike other types of diabetes, gestational diabetes generally does not cause birth defects. Birth defects usually originate sometime during the first trimester of pregnancy. They are more likely in women with pre-existing diabetes, who may have changes in blood glucose during that time. Women with gestational diabetes generally have normal blood sugar levels during the critical first trimester.

The complications of gestational diabetes are usually manageable and preventable. The key to prevention is careful control of blood sugar levels just as soon as the diagnosis of gestational diabetes is made.

Infants of mothers with gestational diabetes are vulnerable to several chemical imbalances, such as low serum calcium and low serum magnesium levels, but, in general, the major problems of gestational diabetes include the following:

  • macrosomia
    Macrosomia refers to a baby that is considerably larger than normal. All of the nutrients the fetus receives come directly from the mother's blood. If the maternal blood has too much glucose, the pancreas of the fetus senses the high glucose levels and produces more insulin in an attempt to use this glucose. The fetus converts the extra glucose to fat. Even when the mother has gestational diabetes, the fetus is able to produce all the insulin it needs. The combination of high blood glucose levels from the mother and high insulin levels in the fetus results in large deposits of fat which causes the fetus to grow excessively large.
  • birth injury
    Birth injury may occur due to the baby's large size and difficulty being born.
  • hypoglycemia
    Hypoglycemia refers to low blood sugar in the baby immediately after delivery. This problem occurs if the mother's blood sugar levels have been consistently high, causing the fetus to have a high level of insulin in its circulation. After delivery, the baby continues to have a high insulin level, but it no longer has the high level of sugar from its mother, resulting in the newborn's blood sugar level becoming very low. The baby's blood sugar level is checked after birth, and if the level is too low, it may be necessary to give the baby glucose intravenously.
  • respiratory distress (difficulty breathing)
    Too much insulin or too much glucose in a baby's system may delay lung maturation and cause respiratory difficulties in babies. This is more likely if they are born before 37 weeks of pregnancy.

High blood pressure and pregnancy:

High blood pressure can occur in pregnancy in two forms. It may be a pre-existing condition, called chronic hypertension, or it can develop during pregnancy - a condition called pregnancy-induced hypertension (PIH). It is also called toxemia or preeclampsia. PIH occurs most often in young women with a first pregnancy. It is more common in twin pregnancies, and in women who had PIH in a previous pregnancy.

High blood pressure can lead to placental complications and slowed fetal growth. If untreated, severe hypertension may cause dangerous seizures and even death in the mother and fetus.

Women with mild PIH may need bedrest. Moderate or severe PIH usually requires hospitalization and medications.

Women with high blood pressure often need to continue taking their antihypertensive medication. Your physician may switch you to a safer antihypertensive medication during pregnancy.

Kidney function tests and ultrasounds are often performed more frequently on pregnant women with high blood pressure to monitor the mother's health and fetal growth and development.

Infectious diseases and pregnancy:

Infections during pregnancy can pose a threat to the fetus. Even a simple urinary tract infection, which is common during pregnancy, should be treated immediately. An infection that goes untreated can lead to premature labor and rupture of the membranes surrounding the fetus. Some infectious diseases include:

  • toxoplasmosis
    Toxoplasmosis is an infection caused by a single-celled parasite named Toxoplasma gondii. Although many people may have Toxoplasma infection, very few have symptoms because the immune system usually keeps the parasite from causing illness. Babies who became infected before birth can be born with serious mental or physical problems. Toxoplasmosis often causes flu-like symptoms, swollen lymph glands, or muscle aches and pains that last for a few days to several weeks. Mothers can be tested to see if they have developed an antibody to the illness. Fetal testing may include ultrasound, and/or testing of amniotic fluid or cord blood. Treatment may include antibiotics. The Centers for Disease Control and Prevention (CDC) recommends the following measures to help prevent toxoplasmosis infection:
    • Wear gloves when you garden or do anything outdoors that involves handling soil. Cats, who may pass the parasite in their feces, often use gardens and sandboxes as litter boxes. Wash your hands well with soap and warm water after outdoor activities, especially before you eat or prepare any food.
    • Have someone who is healthy and not pregnant change your cat's litter box. If this is not possible, wear gloves and clean the litter box daily (the parasite found in cat feces can only infect you a few days after being passed). Wash your hands well with soap and warm water afterwards.
    • Have someone who is healthy and not pregnant handle raw meat for you. If this is not possible, wear clean, latex gloves when you touch raw meat and wash any cutting boards, sinks, knives, and other utensils that might have touched the raw meat. Wash your hands well with soap and warm water afterwards.
    • Cook all meat thoroughly, that is, until it is no longer pink in the center or until the juices run clear. Do not sample meat before it is fully cooked.
  • food poisoning
    A pregnant woman should avoid eating undercooked or raw foods because of the risk of food poisoning. Food poisoning can dehydrate a mother and deprive the fetus of nourishment. In addition, food poisoning can cause meningitis and pneumonia in a fetus, resulting in possible death. Tips for preventing food poisoning include:
    • Thoroughly cook raw food from animal sources, such as beef, pork, or poultry.
    • Wash raw vegetables thoroughly before eating.
    • Keep uncooked meats separate from vegetables and from cooked foods and ready-to-eat foods.
    • Avoid raw (unpasteurized) milk or foods made from raw milk.
    • Wash hands, knives, and cutting boards after handling uncooked foods.
  • sexually transmitted diseases
    • chlamydia - infections such as chlamydia may be associated with premature labor and rupture of the membranes.
    • hepatitis - an inflammation of the liver, resulting in liver cell damage and destruction. Five main types of the hepatitis virus have been identified. The most common type that occurs in pregnancy is hepatitis B (HBV). This type of hepatitis spreads mainly through contaminated blood and blood products, sexual contact, and contaminated intravenous needles. Although HBV resolves in most people, about 10 percent will have chronic HBV. Hepatitis B virus can lead to chronic hepatitis, cirrhosis, liver cancer, liver failure, and death. Infected pregnant women can transmit the virus to the fetus during pregnancy and at delivery.

      The later in pregnancy a mother contracts the virus, the greater the chance for infection in her baby. Signs and symptoms of HBV include jaundice (yellowing of skin, eyes, and mucous membranes), fatigue, abdominal pain, loss of appetite, intermittent nausea, and vomiting. A blood test for hepatitis B is part of routine prenatal testing. HBV positive mothers may receive a drug called hepatitis B immune globulin. Infants of HBV positive mothers should receive hepatitis B immune globulin and the hepatitis B vaccine in the first 12 hours of birth. The American Academy of Pediatrics (AAP) recommends that all babies receive a total of four doses of hepatitis B vaccine to be fully protected against hepatitis B infection.
    • human immunodeficiency virus (HIV) - a woman with human immunodeficiency virus (HIV) has a one in four chance of infecting her fetus. AIDS (acquired immune deficiency syndrome) is caused by the human immunodeficiency virus (HIV), which kills or impairs cells of the immune system and progressively destroys the body's ability to fight infections and certain cancers. The term AIDS applies to the most advanced stages of an HIV infection. HIV is spread most commonly by sexual contact with an infected partner.

      HIV may also be spread through contact with infected blood, especially by sharing needles, syringes, or drug use equipment with someone who is infected with the virus. According to the National Institutes of Health (NIH), HIV transmission from mother to child during pregnancy, labor, and delivery, or by breastfeeding has accounted for nearly all AIDS cases reported among US children.



      Some people may develop a flu-like illness within a month or two after exposure to the HIV virus, although many people do not develop any symptoms at all when they first become infected. Persistent or severe symptoms may not surface for 10 years or more, after HIV first enters the body in adults, or within two years in children born with an HIV infection.

      The Institute of Medicine, the American College of Obstetricians and Gynecologists, the American Academy of Pediatrics, and other health organizations recommend HIV testing of all pregnant women. Prenatal care that includes HIV counseling, testing, and treatment for infected mothers and their children saves lives and resources. Current recommendations are for HIV positive women to take a number of drugs during pregnancy and during labor. Blood tests are also performed to check the amount of virus. Newborn babies of HIV positive mothers may also receive medication. Studies have found this can reduce the chance of a mother's transmission of HIV to the baby from 25 percent to less than 2 percent. Cesarean delivery may be recommended for HIV positive women. This also helps reduce the transmission of the virus to the baby, especially when the mother receives medications. HIV may also be transmitted through breast milk. Studies show that breastfeeding increases the risk of HIV transmission by about 14 percent.

    • herpes - genital herpes can be spread to the baby during delivery, if a woman has an active infection at that time. Herpes is a sexually transmitted disease caused by the herpes simplex virus (HSV). Herpes infections can cause blisters and ulcers on the mouth or face (oral herpes), or in the genital area (genital herpes). HSV is a life-long infection. Symptoms of HSV may include painful blisters or open sores in the genital area, which may be preceded by a tingling or burning sensation in the legs, buttocks, or genital region. The herpes sores usually disappear within a few weeks, but the virus remains in the body and the lesions may recur from time to time.

      It is important that women avoid contracting herpes during pregnancy, because a first episode during pregnancy creates a greater risk of transmission to the newborn. Women may be treated with an antiviral medication such as acyclovir if the disease is severe. Genital herpes can cause potentially fatal infections in babies if the mother has active genital herpes (shedding the virus) at the time of delivery. Cesarean delivery is usually recommended for active genital herpes. Fortunately, infection of an infant is rare among women with genital herpes infection.

      Protection from genital herpes includes abstaining from sex when symptoms are present, and using latex condoms between outbreaks.


http://medicalcenter.osu.edu/patientcare/healthcare_services/pregnancy_childbirth/care/risks_during_pregnancy/index.cfm