NICHD High-Risk Pregnancy Research Information

Institute research on high-risk pregnancy focuses on maternal physiology, environmental variables, and conditions and treatments occurring during pregnancy that affect the health of the mother and fetus.

Topics of interest include:

• Pathophysiological states of pregnancy
• Prevention of preterm birth
• The health impact on mother and infant of pregnancy-related disorders
• Understanding the effects of pregnancy on women with chronic medical conditions and disabilities
• Pathogenesis of maternal infections and their effects on fetal development
• The effect of maternal medications and a mother’s use and abuse of drugs on fetal development
• Adolescent pregnancy

Understanding pregnancy processes and fetal development can pave the way for predicting and preventing poor pregnancy outcomes for mothers and their newborns in the United States and around the world.

Institute Activities and Advances

Several components of NICHD support and conduct research on high-risk pregnancies, the conditions that are associated with high-risk pregnancies, and treatments and interventions to promote the best outcomes for high-risk pregnancies.

Research supported by the Pregnancy and Perinatology Branch (PPB) addresses many aspects of high-risk pregnancy, from preterm labor and birth and preeclampsia and eclampsia to understanding how the placenta develops and functions and what interventions can help improve survival of infants born at very low birth weight and/or extremely preterm. Some recent announcements and findings from PPB-supported studies include:

• NIH-funded study to focus on newborns affected by opioids
• Probiotics may prevent life-threatening infection in newborns
• NIH-led workshop addresses opioid misuse during pregnancy
• Common tests for preterm birth not useful for routine screening of first-time pregnancies
• No benefit in treating mildly low thyroid function in pregnancy, NIH Network study finds
• Survival rate may be improving for extremely preterm infants

The Maternal and Pediatric Infectious Disease Branch (MPIDB) supports research on the effects of different infections, such as HIV/AIDS and Zika, on pregnancy and pregnancy outcomes, including congenital infection syndromes. Some recent announcements and findings from branch-supported work include:

• NIH begins large HIV treatment study in pregnant women
• Zika infection during pregnancy may disrupt fetal oxygen supply
• Spotlight: Zika research after Hurricane Maria
• Malaria drug protects fetal mice from Zika virus, NIH-funded study finds
• NIH launches prospective study of Zika and HIV co-infection during pregnancy
• Focusing on Zika’s threat to child development
• Antiviral drug not beneficial for reducing mother-to-child transmission of hepatitis B when added to existing preventatives, study shows

The Division of Population Health Research studies different aspects of high-risk pregnancy and ways to increase positive pregnancy outcomes from high-risk pregnancy. Some recent findings from the division include findings related to gestational diabetes and environmental exposures, as well as multiple gestations:

• Air pollution exposure in early pregnancy linked to miscarriage, NIH study suggests
• Obesity during pregnancy may lead directly to fetal overgrowth, NIH study suggests
• Second trimester weight gain associated with fetal growth in twin pregnancies
• NICHD research links air pollution and extreme temperature to stillbirth risk
• Extreme temperatures may increase risk for low birth weight at term, NIH study suggests
• Aspirin may help increase pregnancy chances in women with high inflammation, NIH study finds
• Cigarette smoking during pregnancy linked to changes in baby’s immune system

The Perinatal Research Branch within the Division of Intramural Research studies pregnancy outcomes among high-risk pregnancies and ways to improve those outcomes. For more information on the branch’s work, visit https://annualreport.nichd.nih.gov/romero.html.

Other NICHD components also study ways to improve outcomes for high-risk pregnancies. For example, the National Center for Medical Rehabilitation Research supports studies of pregnancies in women with physical disabilities. The Pediatric Growth and Nutrition Branch investigates how nutrition affects pregnancy and fetal development, as well as the range of outcomes related to gestational diabetes. The Obstetric and Pediatric Pharmacology and Therapeutics Branch (OPPTB) studies the safety and efficacy of medications used during pregnancy, including those used to treat chronic conditions such as depression.

Other Activities and Advances

• The PPB supports the Maternal-Fetal Medicine Units (MFMU) Network. Established in 1986, the MFMU network focuses on clinical questions in maternal-fetal medicine and obstetrics, including maternal health, fetal health and development, gestational diabetes, asthma, thyroid disorders, and preterm labor.
• Research on mother-to-child transmission of HIV/AIDS, complications of HIV infection in pregnant women, and drug treatment are carried out through the following supported networks:
  • International Maternal, Pediatric, Adolescent AIDS Clinical Trials (IMPAACT) Network (supported by the MPIDB)
  • NICHD Domestic and International Pediatric & Maternal HIV Clinical Studies Network (supported by the MPIDB)
• The Maternal-Fetal Surgery Network, also supported by the PPB, was created to conduct a clinical trial to evaluate the efficacy of in utero surgery versus standard post-natal surgery to repair myelomeningocele, the most severe form of spina bifida. The study, called the Management of Myelomeningocele Study (MOMS), began in 2003 and found that surgery reduced the chance of death by one-third; however, it also increased the risk of preterm birth. The network is currently conducting a follow-up study, MOMS2 , to evaluate outcomes of the children at 5 to 8 years.
• Another study, called the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b), also led by the PPB, is evaluating nulliparous pregnancy outcomes to determine factors that can influence or predict adverse outcomes such as preeclampsia, preterm birth, and fetal growth restriction.
• The OPPTB supports the Maternal and Pediatric Precision in Therapeutics (MPRINT) Hub, which conduct research on the safety and efficacy of medication use during pregnancy. Current studies include evaluating pravastatin for the prevention of preeclampsia and broader studies on the use of a range of medications from antibiotics to antidepressants.
• Funded by the Pediatric Growth and Nutrition Branch from 2000 through 2006, the Hyperglycemia and Adverse Pregnancy Outcomes study enrolled 23,316 mother-child pairs at 15 clinical centers in nine countries. The study found that a mother’s blood sugar levels were associated with her newborn’s birth weight and body fat. Importantly, the study also found that women with higher glucose levels were at increased risk for cesarean delivery.
• Since its launch in 2015, NIH has invested more than $50 million in the Human Placenta Project, which aims to develop new tools to study the placenta in real time to better understand how it develops and functions during pregnancy. The knowledge gained may one day help prevent and treat a range of common pregnancy complications.
• The Global Network for Women’s and Children’s Health Research supports and conducts clinical research projects in resource-limited countries to evaluate low-cost, sustainable interventions to improve maternal and infant health. The Global Network began in 2001 as a private-public partnership between NICHD and the Bill and Melinda Gates Foundation. Today, the network includes efforts in India, Pakistan, Guatemala, Zambia, Kenya, and the Democratic Republic of Congo and a wide range of projects aimed at improving pregnancy outcomes and increasing neonatal survival.