Understanding Preterm Birth: Risk Factors, Prevention and What to Expect
By Dr Greg Jenkins | Sydney-based specialist in Fertility, Obstetrics and Gynaecology
When you are expecting a baby, reaching full term is always the goal. Most pregnancies last about 40 weeks, but sometimes babies arrive earlier than planned. Preterm birth is when a baby is born before 37 completed weeks of pregnancy. As an obstetrician in Sydney, I have supported many families through the unique challenges of preterm birth. This article will help you understand the risk factors, ways to reduce the chance of early delivery and what to expect if your baby arrives early.
What is Preterm Birth?
Preterm birth is classified into three main categories:
Late preterm: Babies born between 34 and 36 weeks.
Very preterm: Babies born between 28 and 33 weeks.
Extremely preterm: Babies born before 28 weeks.
The earlier a baby is born, the greater the chance of needing specialist care such as time in a neonatal intensive care unit (NICU). However, with modern obstetric and neonatal care, survival rates have improved significantly, even for very early babies.
Risk Factors for Preterm Birth
Some risk factors are outside your control, while others can be managed with medical care and lifestyle changes. Common risk factors include:
Multiple pregnancy: Twins or triplets are more likely to arrive early.
Previous preterm birth: A history of early delivery can increase future risk.
Medical conditions: High blood pressure, diabetes, or infections during pregnancy.
Uterine or cervical factors: Conditions like a short cervix or structural concerns.
Placental complications: Such as placental abruption or placenta previa.
Lifestyle factors: Smoking, poor nutrition, illicit drug use.
Most commonly there is no clear cause. Even with no known risk factors, preterm birth can still occur.
Signs of Preterm Labour
Knowing the warning signs can help you act quickly. Contact your care team if you experience:
Regular contractions before 37 weeks.
Vaginal bleeding or fluid leakage.
Pelvic pressure or cramping that feels unusual.
Early assessment is important because sometimes preterm labour can be delayed or prevented with the right treatment.
Preventing Preterm Birth
Not every case can be prevented, but there are steps that can reduce the risk.
Regular antenatal care: Early and consistent check-ups help identify risks sooner.
Treating infections: Prompt treatment of urinary tract or other infections is essential.
Managing chronic conditions: Good control of diabetes, hypertension, or thyroid disease.
Targeted Cervical length monitoring: For women with a history of preterm birth vaginal progesterone medication should be considered, ultrasounds may guide other treatments like cervical cerclage (a stitch to help keep the cervix closed).
Lifestyle factors: Stopping smoking, improving nutrition and reducing stress levels all support a healthy pregnancy.
Routine cervical length monitoring: routine measurement of the length of the cervix should be offered to all women at the time of the 20 week pregnancy ultrasound. If the cervix is less than 25mm long there may be an increased risk of preterm birth and there are some treatments which can reduce this risk.
For some high-risk patients, additional scans or specialist referrals may be part of the plan.
What to Expect if Your Baby is Born Early
If preterm birth looks likely, we prepare carefully. This often includes:
Corticosteroid injections: To help your baby’s lungs mature more quickly.
Magnesium sulphate: For brain protection if delivery is expected before 32 weeks.
Choosing the right hospital: Facilities with a NICU give your baby access to the best immediate care.
After birth, many premature babies spend time in a NICU or special care nursery. The length of stay depends on how early the baby was born and their progress with feeding, breathing and maintaining temperature.
Long-Term Outcomes
Most babies born after 32–34 weeks do very well with modern care. Extremely premature babies may face more challenges, but advances in neonatal medicine mean survival and quality of life have improved dramatically over the past two decades. It is essential that for very preterm and extremely preterm babies discussions be individualised to your particular circumstance.
Emotional Support for Families
Preterm birth can be overwhelming. Families often need emotional as well as medical support. Counselling services, parent support groups and social workers linked to the hospital can help guide you through the early days and weeks.
Final Thoughts
Preterm birth is something no parent plans for, but with early detection, specialist care and good planning, outcomes are often excellent. If you have concerns about your pregnancy or risk factors for preterm birth, talk to your obstetrician early so we can create a plan tailored to you and your baby’s needs.
Meet Dr. Greg Jenkins: Your Partner in Fertility and Obstetrics
Dr Greg Jenkins is a specialist obstetrician, fertility specialist and gynaecologist, and the Head of Obstetrics and Gynaecology at Westmead Public Hospital. He provides personalised care for women and couples across fertility treatment, pregnancy and birth — with the unique advantage of continuity of care from conception through to delivery.
Dr Jenkins consults privately at Norwest Private Hospital in Bella Vista and works in partnership with Minerva Fertility at Bond Day Hospital. He offers delivery at Norwest Private, Westmead Private and Westmead Public Hospital, giving families flexibility in choosing the setting that best suits their needs.
