Babies born at 33 weeks are considered to be moderately preterm, and most of them require medical assistance to get healthy. Read on to learn more about the complications that babies born at 33 weeks often face and how to care for your preterm baby.
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Everything About Babies Born at 33 Weeks
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
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Find out moreOverview of a baby born at 33 weeks
Preterm births occur before week 37 of pregnancy. Premature babies are at a higher risk of having various health problems and developmental complications. These complications are usually more serious the earlier a baby is born.
Premature babies can be classified as:
- Late preterm — born between weeks 34 and 36 of pregnancy
- Moderately preterm — born between weeks 32 and 34 of pregnancy
- Very preterm — born before week 32 of pregnancy
- Extremely preterm — born at or before week 25 of pregnancy
This means that babies born at 33 weeks are considered to be moderately preterm. Fortunately, modern science has greatly improved the survival rate of babies born at 33 weeks. Babies born at this stage have a 95 percent chance of survival.
On average, babies born at 33 weeks weigh around 3 pounds and 15.5 ounces (1.8 kilograms). They are typically around 16.5 inches (42 centimeters) long.
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Causes of premature birth
The reasons why a baby is born before they reach full term aren’t always clear. Many pregnant women experience premature birth without any prior risk factors. However, there are certain risks factors for premature birth, including:
- Multiple pregnancies
- Maternal infections, such as urinary tract infections, vaginal infections, and amniotic fluid infections
- Diabetes
- Maternal abnormalities of the reproductive system
- High blood pressure
- A short interval between pregnancies (six months or less)
- Past history of preterm deliveries
- Smoking during pregnancy
- Alcohol or drug use during pregnancy
- Nutrition problems before pregnancy, such as being underweight or overweight
- Poor prenatal care
- Recurrent pregnancy loss
- Stressful life events during pregnancy
- Physical trauma during pregnancy
In some cases, doctors need to induce premature labor when the mother has serious health complications such as preeclampsia.
Complications for a baby born at 33 weeks
Babies born at 33 weeks of pregnancy can face different complications immediately after birth and during their long-term development. Some of the most common complications associated with premature birth before 34 weeks include:
- Small size
- Sepsis (infection)
- Hypoglycemia (low blood sugar)
- Respiratory distress
- Pneumonia
- Patent ductus arteriosus (an opening between major blood vessels in the heart)
- Jaundice
- Anemia
- Temperature instability
- Retinopathy or damage to the retina
- Necrotizing enterocolitis (a bacterial infection of the intestines)
- Feeding problems
- Intraventricular hemorrhage (bleeding) of the brain
- Bronchopulmonary dysplasia (chronic lung disease)
Moderately preterm babies can also develop long-term complications that may need early intervention and continuous support, such as special education or different types of therapy. These developmental complications can include:
- Delayed cognitive development
- Delayed motor and language skill development
- Impaired attention, focus, and memory
- Behavioral problems
- Cerebral palsy
How to take care of a premie
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A baby born at 33 weeks will probably need to spend some time in the neonatal intensive care unit, even if their condition is stable after birth. This allows your baby’s doctors to keep a close eye on them.
Your baby will probably be placed in an incubator to help regulate their body temperature. Once they’re stable, you’ll probably be encouraged to provide skin-to-skin contact. Doctors and nurses will monitor your baby’s vital signs and use equipment to help them breathe if necessary.
At first, your baby may need some help to get enough nutrition. They may receive intravenous fluids, nutrients, and electrolytes, or a nasogastric tube may be passed from their stomach to their nose to feed them milk. Once they’re strong enough to eat on their own, breastfeeding or bottle feeding will be encouraged.
Jaundice is a common complication of preterm birth, and your baby could be placed under special lights to prevent or treat this issue. A nurse will place a mask over your baby’s eyes to protect them while they’re under the bilirubin lights. If necessary, your baby could also receive blood transfusions.
Your baby may also require certain medications, which could include:
- The surfactant to treat respiratory distress
- Antibiotics to treat or prevent infections
- Diuretics to increase their urine output
- Eye medications to prevent retinopathy
- Medications to close patent ductus arteriosus
Some moderately premature babies may require surgical procedures to treat different complications. Communicate with your baby’s medical team to get more information about their condition and stay updated on their treatment plan.
Your baby’s medical team may announce that your baby is ready to go home when they:
- Can breathe on their own
- Can regulate their body temperature
- Can eat, whether they breastfeed or bottle feed
- Are gaining weight satisfactorily
- Don’t have any infectious complications
Your baby’s team will talk to you about how you should monitor your baby and any care requirements. They’ll also tell you when to bring them in for a checkup after being discharged and how to organize living and care arrangements for your baby.
Babies born at 33 weeks, in summary
Sometimes, pregnancy can seem very long. However, it’s always ideal for your baby to be born full term. Babies born at 33 weeks may face complex medical issues that require a stay in intensive care and continued treatment. However, modern treatments have greatly improved the prognosis for preterm babies.
References
History of updates
Current version (27 August 2021)
Published (04 January 2020)
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