Clinicians generally consider fetal viability to be the point at which an infant can be resuscitated at birth and survive without significant morbidity. Often this age of viability is approximate24 weeks gestation.
Many pregnant women, especially those who have already experienced a miscarriage, look forward to this milestone and breathe a sigh of relief when they reach it. But determining when a fetus is viable is difficult, and many factors affect survival and preterm outcomes.
How far along you are in the pregnancy plays a big role in determining viability. The exact age of viability continues to pose an ethical dilemma, particularly about when and how much intervention should be performed, since the earlier the baby is born, the greater the risk of death and morbidity.
Viability is also a moving target that varies depending on the quality of healthcare a baby has access to and where in the world the baby is born.
In many hospitals, 24 weeks is the time when doctors take action to save a premature baby's life.This usually means extreme medical intervention, possibly including mechanical ventilation and other invasive treatments, followed by a prolonged stay in oneNeonatal Intensive Care Unit (NICU).
The baby may also need tubal support to eat and breathe. Some hospitals may consider it if a baby is born even earlier, despite the increased potential for complications, disability, and death.
22 to 23 weeks
In the hands of experienced specialists in state-of-the-art neonatal intensive care units, babies born around 24 weeks may have a chance of survival. But unfortunately, that chance is slim and the outcomes for those who survive are not the best.
Babies born at or before 23 weeks who survive are much more likely to suffer major complications and/or permanent disabilities than those who remain in the womb for a few weeks.A 2015 study showed that babies born at 22 weeks of age may also have little chance of survival, but are even more likely to die or have serious health problems.
Also keep in mind that according to the American College of Obstetricians and Gynecologists, babies born before 23 weeks only have a 5% to 6% survival rate. Of those who survive, between 98% and 100% experience significant complications and/or disability.
The chances of survival increase as the pregnancy progresses, and even one more week in the womb can make a big difference. Generally,prematureborn closer37 weeksthey will be better off than those born before28 weeks.
For example, one study found that overall survival and unaffected survival rates for babies born at 22 weeks' gestation ranged from 5.1% to 3.4%, respectively. For 26 weeks of gestation, the percentages were significantly higher with a survival rate of 81.4% and an impairment-free survival rate of 75.6%.
It's also important to note that these rates largely depend on several factors, including why the baby was born early and where the baby is cared for.
What is considered a preterm birth?
According to the Centers for Disease Control and Prevention (CDC), thepremature birththe rate is about 10%, with a higher incidence in younger mothers (teenagers), blacks (14.4% vs. 9.3% in white women and 10% in Hispanic women), and older mothers (35 years or older). further).
Very preterm births account for approximately 1.6% of all live births in the United States.To get a better idea of how preterm births are classified, doctors break down the gestational week intervals as follows:
- extremely premature: Gestational age equal to or less than 28 weeks
- very premature: Gestational age equal to or less than 32 weeks
- moderately premature: gestational age between 32 weeks and 33 weeks and 6 days
- late prematurity: gestational age between 34 weeks and 36 weeks and 6 days
Keep in mind that the vast majority of preterm births occur in the late preterm period.
What is leaky birth?
A preterm birth is a near viable birth, generally defined between 23 and 26 weeks of gestation. A birth before the 23rd week of pregnancy is generally considered to be foreseeable, i. h there is practically no chance of survival.
Factors Affecting Fetal Viability
Several factors can influence whether or not a baby survives a preterm birth, including:
- birth weight: Bigger babies have better survival rates.low birth weightit is independently associated with a reduced chance of survival and an increased risk of disability and health problems.
- complications: Se opremature birthResult of an induction or caesarean section due to a medical condition such asplacental solutionor lack of oxygen before birth, this condition can affect the health and survival of the baby.
- number of babies: Single preterm births are more likely to be viable than multiple preterm births.
- lack of oxygen: Complications of labor that limit fetal respiration, e.g. B. when the umbilical cord is wrapped around the neck, it can affect survival rates.
- Sex: In general, girls have higher survival rates than boys.
- prenatal steroid treatment: Steroids taken by the mother before birth accelerate lung development and improve the chances of survival. Steroids can help the baby breathe outside the womb.
A baby's brain undergoes tremendous growth and development during the last weeks of pregnancy. Therefore, babies who are born very early and survive have a high chance of experiencing some level of long-term effects.
The severity of these effects depends on many factors, including the need for and the type of treatment received. Typically, the more intense the life-saving treatments, the greater the risk factors for these extremely small and fragile babies.
However, it is difficult to say exactly which babies will have problems and how severe those problems will be later in life. Some common long-term consequences of giving birth too early are:
- Cerebral palsy: This common neurological movement disorder occurs due to abnormal brain development or injury.
- chronic health problems: These include the added risk of epilepsy, heart disease, nutritional problems, infections, asthma, and sudden infant death syndrome (SIDS).
- cognitive decline: Premature birth can affect a child's intellectual development.
- developmental delays: Premature babies often reach milestones later and grow more slowly.
- hearing or vision problems: Vision and hearing problems are common in premature babies.
- learning difficulties: These children often havelearning difficultiesor other developmental disabilities, but the severity of the impairments or impairments can vary widely.
- Mental illness: Preterm birth is associated with higher rates of social/emotional problems, such as anxiety, behavioral problems, and depression.
Some facts to keep in mind:
- Between 20% and 50% of premature babies born before 28 weeks have permanent complications.
- About 80% of babies are born in26 weeks pregnantwill have long-term physical or developmental problems.
What to ask your provider
If you are expecting to deliver an extremely premature baby, start a discussion with your baby's healthcare provider about what type of CPR you would like your baby to have at what stage of pregnancy.
This is certainly a difficult situation. However, by considering these issues before they arise, you can ask all the pertinent questions and think through these difficult decisions before they need to be made.
Questions to ask
Parents who experience preterm labor or have had one unexpectedly should ask themselves:
- At what gestational age was my baby born (or will be born)?
- Was the baby deprived of oxygen before birth? What are the expected consequences of this? What tests have been performed to verify severity?
- What issues should I be aware of after launch? In the first year? When does my child start school?
- What care does my baby need? Is there an early education program?
- What types of interventions have been or are being used in my baby's care? What are the risks and benefits of each of these treatments? What are the alternatives?
A word from Verywell
There are so many variables to consider when delivering a premature baby, both for parents and healthcare professionals. It's not just a discussion about whether the baby survives delivery, but what the long-term consequences are for your baby.
If your baby was born prematurely, or you are expecting your baby to be born prematurely, talk at length with your baby doctor so that you are as prepared and cared for as possible.the support you need. Parent support groups are invaluable to you and others.
Long-term consequences of preterm birth
Verywell Family uses only quality sources, including peer-reviewed studies, to support the facts in our articles. read ourspublishing processfor more information on how we verify our content and keep it accurate, reliable, and trustworthy.
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Krissi Danielsson, MD, is a family medicine physician and advocate for people who have suffered a miscarriage.
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