Pregnancy Risk Factors
Pregnancy is the period from conception to birth and is the time of the growth and development of one or more children in the uterus of a woman.
What is the information for this topic?
A pregnancy is considered to be at risk when a problem is more likely than usual to occur. Such a problem could be caused by a health condition the mother had before she was pregnant. It could also be a problem that arises during pregnancy or delivery.
The women who have known risk factors account for greatest percent of the problems that occur. However, not all problems can be predicted. About 1 in 5 infants who have serious problems are born to mothers who had no known risk factors during pregnancy.
The following health problems in the mother can increase the risk of her pregnancy:
- high blood pressure
- heart disease, lung disease, or liver disease
- sexually transmitted infections, or STIs
- urinary tract infections
- viral or bacterial infections
- diabetes, which means that sugar in the blood is difficult to control
- severe asthma
- seizure disorders or epilepsy
- posttraumatic stress disorder
- hypothyroidism, or a low level of thyroid hormone production
Problems related to the current pregnancy or past pregnancies can increase the risk to the mother and baby, such as:
- problems in past pregnancies
- adolescent pregnancy, especially pregnancy in a mother who is younger than 15 years of age
- advanced maternal age, which means pregnancy in a woman older than 35 years of age
- previous birth defects
- multiple fetuses, for example, twins or triplets
- pregnancies that are less than 6 months or more than 5 years apart
- vaginal bleeding, especially during the second trimester or third trimester
- preeclampsia, which is pregnancy-induced high blood pressure associated with certain other problems
- abnormal heartbeat in the baby
- intrauterine growth restriction (UGR), a condition in which a baby is not growing properly for his or her gestational age
Lifestyle issues in the mother that can increase her pregnancy risk factors are as follows:
- drinking alcohol
- caffeine intake, particularly in the first trimester
- taking drugs and herbal remedies not prescribed by a healthcare provider
- poor nutrition, including low levels of folic acid
- lack of prenatal care
- multiple sexual partners
- exposure to pesticides
To screen for risk factors, several lab tests are done at different times during pregnancy, including the following:
- blood tests to identify blood type and Rh factor, to check for a low red blood cell count caused by anemia, and to detect some sexually transmitted diseases
- urine tests to check levels of sugar, protein, and bacteria. These urine tests screen for urinary tract infections, gestational diabetes, and preeclampsia.
Depending on the mother's medical history, family medical background, and the results of routine tests, more tests to check the growth and health of the baby may be suggested.
Genetic counseling is strongly advised for couples with a risk factor of having a child with a birth defect or serious genetic illness.
Risk factors for this are as follows:
- a mother who will be 35 years old or older when the baby is due
- a family or personal history of birth defects, genetic conditions such as Tay-Sachs disease or Down syndrome, or certain medical disorders known as inborn errors of metabolism
- a previous child with a birth defect or genetic disease such as sickle cell anemia
- certain ethnic backgrounds, including African-American, Mediterranean, Asian, French-Canadian, or Ashkenazi Jewish
- 3 or more miscarriages in a row
Planning for Pregnancy, Birth and Beyond. Second Edition The American College of Obstetricians and Gynecologists
What to Expect when You're Expecting, Eisenberg