Fetal distress, also known as non-reassuring fetal status, is a condition during pregnancy or labor in which the fetus shows signs of inadequate oxygenation. Due to its imprecision, the term "fetal distress" has fallen out of use in American obstetrics. The term "non-reassuring fetal status" has largely replaced it. It is characterized by changes in fetal movement, growth, heart rate, and presence of meconium stained fluid. Risk factors for fetal distress/non-reassuring fetal status include anemia, restriction of fetal growth, maternal hypertension or cardiovascular disease, low amniotic fluid or meconium in the amniotic fluid, or a post-term pregnancy. The condition is detected most often with electronic fetal heart rate (FHR) monitoring through cardiotocography (CTG), which allows clinicians to measure changes in the fetal cardiac response to declining oxygen. Specifically, heart rate decelerations detected on CTG can represent danger to the fetus and to delivery. Treatment primarily consists of intrauterine resuscitation, the goal of which is to restore oxygenation of the fetus. This can involve improving the position, hydration, and oxygenation of the mother, as well as amnioinfusion to restore sufficient amniotic fluid, delaying preterm labor contractions with tocolysis, and correction of fetal acid-base balance. An algorithm is used to treat/resuscitate babies in need of respiratory support post-birth.

Signs and symptoms

Generally it is preferable to describe specific signs in lieu of declaring fetal distress that include: Some of these signs are more reliable predictors of fetal compromise than others. For example, cardiotocography can give high false positive rates, even when interpreted by highly experienced medical personnel. Fetal acid-base status is a more reliable predictor, but is not always available.

Complications

Complications are primarily those associated with insufficient fetal oxygenation, most notably increased mortality risk. Other complications include fetal encephalopathy, seizures, cerebral palsy, and neurodevelopmental delay.

Causes

Several conditions and risk factors can lead to fetal distress or non-reassuring fetal status, including:

Prevention

Monitoring of the mother and fetus prior to birth is critical to avoid complications after birth. This is often done via electronic fetal heart rate (FHR) monitoring, which helps providers monitor the fetus' heart rate to ensure it is receiving enough oxygen, monitor the mother's contractions, and monitor the mother's blood pressure and systemic symptoms for gestational hypertension, preeclampsia, or eclampsia.

Treatment

Instead of referring to "fetal distress", current recommendations hold to look for more specific signs and symptoms, assess them, and take the appropriate steps to remedy the situation through the implementation of intrauterine resuscitation. Traditionally the diagnosis of "fetal distress" led the obstetrician to recommend rapid delivery by instrumental delivery or by caesarean section if vaginal delivery is not advised. An algorithm is used to treat/resuscitate babies in need of respiratory support post-birth. The algorithm steps include: clearing the airways and warming, stimulating, and drying the baby, positive-pressure ventilation (PPV), supplementary oxygen, intubation, chest compressions, and pharmacological therapy. The order of these interventions is set, and each step is done for 30 seconds with heart rate monitoring and assessment of chest movement prior to escalating to the next step in the algorithm.