Risk factors in pregnancy

Factors increasing the risk (to either the woman, the fetus/es, or both) of pregnancy beyond the normal level of risk may be present in a woman's medical profile either before she becomes pregnant or during the pregnancy. These pre-existing factors may relate to physical and/or mental health, and/or to social issues, or a combination.

Common risk factors

Some common factors include:

• Age of either parent
  • Adolescent parents
    Further information: Teenage_pregnancy#Medical_outcomes
  • Older parents
    Further information: Paternal age, Maternal age effect, and Pregnancy over age 50
• Teratogens
  Main article: Teratology
  • Drug use or addiction
    • Alcohol Fetal alcohol syndrome, Fetal alcohol spectrum disorder
    • Tobacco Smoking and pregnancy
    • See also Prenatal cocaine exposure, Prenatal methamphetamine exposure, Long-term effects of cannabis#Pregnancy
  • Medication(s). Anti-depressants, for example, may increase risks of such outcomes as preterm delivery.
    Further information: Pregnancy category
  • Ionizing radiation
• Risks arising from previous pregnancies:
  • Complications experienced during a previous pregnancy are more likely to recur.
  • Many previous pregnancies. Women who have had five previous pregnancies face increased risks of very rapid labor and excessive bleeding after delivery.
  • Multiple previous fetuses. Women who have had more than one fetus in a previous pregnancy face increased risk of mislocated placenta.
    Further information: multiple births

• Social and socioeconomic factors. Generally speaking, unmarried women and those in lower socioeconomic groups experience an increased level of risk in pregnancy, due at least in part to lack of access to appropriate prenatal care.
• Unintended pregnancy. Unintended pregnancies preclude preconception care and delays prenatal care. They preclude other preventive care, may disrupt life plans and on average have worse health and psychological outcomes for the mother and, if birth occurs, the child.
• Height. Pregnancy in women whose height is less than 1.5 meters (5 feet) correlates with higher incidences of preterm birth and underweight babies. Also, these women are more likely to have a small pelvis, which can result in such complications during childbirth as shoulder dystocia.
• Weight
  • Low weight: Women whose pre-pregnancy weight is less than 45.5 kilograms (100 pounds) are more likely to have underweight babies.
  • Obese women are more likely to have very large babies, potentially increasing difficulties in childbirth. Obesity also increases the chances of developing gestational diabetes, high blood pressure, preeclampsia, experiencing postterm pregnancy and/or requiring a cesarean delivery.

Disorders and diseases

Pre-existing disorders and/or congenital defects can increase the usual risks involved in pregnancy. In such circumstances, women who wish to continue with a pregnancy require extra medical care, often from an interdisciplinary team. Such a team might include (besides an obstetrician) a specialist in the disorder and other practitioners (for example, maternal-fetal specialists, nutritionists, etc.).

These conditions include:

• Cancer
• Chronic hypertension
• Cirrhosis
• Congenital disorders that may be passed on to offspring
• Diabetes
• Heart defects, especially primary pulmonary hypertension and Eisenmenger's syndrome
• Hyperthyroidism
• Hypothyroidism
• Kidney disorders
• Lupus
• Mental health.
  • Depression has been linked to higher rates of preterm delivery.
• Respiratory disorders and diseases (associated, for example, with placental abruption)
  • Asthma
• Seizure disorders
• Structural abnormalities in the cervix
• Structural abnormalities in the uterus
• Valvular heart disease
• Viral hepatitis

High-risk pregnancy

Some disorders and conditions can mean that pregnancy is considered high-risk (about 6-8% of pregnancies in the USA) and in extreme cases may be contraindicated. High-risk pregnancies are the main focus of doctors specialising in maternal-fetal medicine.

Serious pre-existing disorders which can reduce a woman's physical ability to survive pregnancy include a range of congenital defects (that is, conditions with which the woman herself was born, for example, those of the heart or reproductive organs, some of which are listed above) and diseases acquired at any time during the woman's life.

Low-risk pregnancy

A Dutch 2010 research showed that "low-risk" pregnancy in the Netherlands may actually carry a higher risk of perinatal death than a "high-risk" pregnancy. A medical news report observed, "Under the Dutch system of obstetric care, women with low-risk pregnancies are supervised by a midwife in primary care, with the choice of a home or hospital delivery, whereas those with potential complicating factors are supervised by an obstetrician throughout their pregnancy and given a hospital delivery".

Pregnancy and Teratogens

The existence of teratogens in the environment is a very real issue that some do not realize can affect an unborn child. The environment is something we can all take for granted, however is also something we do not realize can cause harm to us or the potential of an unborn child. The exposure to pesticides in the air and even over-exposure to the sun can contain teretogens that can be harmful to all of us. Unfortunately the abuse of alcohol and illegal drugs is a real problem when it comes to pregnancy and also to the mother and baby’s health. Of course the most healthy way to conceive is to plan ahead of time, however this is most often not the case even if a couple is in the family planning stage. No one can pinpoint when the date of conception will be, so knowing when to have one last drink, cigarette or whatever substance is almost impossible. Teretogens can be harmful and affect the development of an unborn as well as a developing infant. The parents must do everything possible to avoid directly affecting the reflexes, motor skills and physical development of the child that is within their control. This includes abstinence from harmful chemicals that are known to contribute to birth defects, learning and behavioral disorders and other conditions that can harm a child at this stage of life. Reference: Lucile Packard Children’s Hospital at Stanford. Effects of Teratogens. 2013. Web. 20 April 2013. http://www.lpch.org/DiseaseHealthInfo/HealthLibrary/genetics.tover.html