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Overview of High-Risk Pregnancy

By

Raul Artal-Mittelmark

, MD, Saint Louis University School of Medicine

Last full review/revision Sep 2020| Content last modified Sep 2020
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Topic Resources

In a high-risk (at-risk) pregnancy, the mother, fetus, or neonate is at increased risk of morbidity or mortality before, during, or after delivery.

In 2017, overall maternal mortality rate in the US was 19/100,000 deliveries, as estimated by the WHO; incidence is 3 to 4 times higher in nonwhite women. Almost 50% of pregnancy-associated deaths in the US occur in non-Hispanic black women. The maternal mortality rate is higher in the US than in other Western countries (eg, Germany, Netherlands, Poland, Spain, Sweden, Switzerland, United Kingdom).

Maternal mortality ratios in selected countries

Maternal mortality ratio refers to the number of women who die from pregnancy-related causes during pregnancy or within 42 days of the end of the pregnancy per 100,000 live births. In 2017, ratios ranged from 2 (Poland) to 1150 (South Sudan) per 100,000 live births (countries not shown). The maternal mortality ratio is higher in the US than in other Western countries.

Maternal mortality ratios in selected countries

Data from the World Health Organization, United Nations Children’s Fund (UNICEF), United Nations Population Fund (UNFPA), The World Bank, and the United Nations Population Division. Trends in Estimates of Maternal Mortality Ratio (MMR; Maternal Deaths per 100,000 Live Births) 2000–2017. Geneva, World Health Organization, 2019.

Disparities by race and ethnicity in maternal mortality are significant worldwide. In the US, the maternal mortality rate is 3.3 times higher in black women and 2.5 times higher in American Indian and Alaska native women than in white women (1 References In a high-risk (at-risk) pregnancy, the mother, fetus, or neonate is at increased risk of morbidity or mortality before, during, or after delivery. In 2017, overall maternal mortality rate in... read more ). In Brazil, the maternal mortality is about 5 times higher in women of African descent than in white women; in the United Kingdom, it is higher in black women than in white women (2 References In a high-risk (at-risk) pregnancy, the mother, fetus, or neonate is at increased risk of morbidity or mortality before, during, or after delivery. In 2017, overall maternal mortality rate in... read more ).

The most common causes of maternal death worldwide are

  • Delay in seeking assistance by the patient and family

  • Lack of transportation

  • Delay in providing assistance at a health care facility

Perinatal mortality rate in offspring in the US is about 6 to 7/1000 deliveries; deaths are divided about equally between those during the late fetal period (gestational age > 28 weeks) and those during the early neonatal period (< 7 days after birth).

The most common causes of perinatal death are

Other maternal characteristics that increase the risk of perinatal mortality include maternal age (much younger or older than average), unmarried status, smoking, and multiple gestations.

References

Risk Assessment During Pregnancy

Several pregnancy monitoring and risk assessment systems are available. The most widely used system is the Pregnancy Assessment Monitoring System ( PRAMS), which is a project of the Centers for Disease Control and Prevention (CDC) and state health departments. PRAMS provides information for state health departments to use to improve the health of mothers and infants. PRAMS also enables the CDC and states to monitor changes in health indicators (eg, unintended pregnancy, prenatal care, breastfeeding, smoking, drinking, infant health).

High-risk pregnancies require close monitoring and sometimes referral to a perinatal center, especially if women have complex high-risk conditions. These centers offer many specialty and subspecialty services, provided by maternal, fetal, and neonatal specialists (1 Risk assessment reference In a high-risk (at-risk) pregnancy, the mother, fetus, or neonate is at increased risk of morbidity or mortality before, during, or after delivery. In 2017, overall maternal mortality rate in... read more ). When referral is needed, transfer before rather than after delivery results in lower neonatal morbidity and mortality rates.

The most common reasons for referral before delivery are

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Risk assessment reference

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