Preterm birth, Causes, signs, and prevention

Preterm birth, Causes, signs and prevention


Preterm birth is defined as babies born alive before 37 weeks of pregnancy are completed. Preterm birth is also sub-categories based on gestational age as extremely preterm (less than 28 weeks), very preterm (28-32 weeks), moderate to late preterm (32-37 weeks. According to World Health Organization (WHO); every year, an estimated 15 million babies are born preterm, preterm birth problems accounted for just around 1 million fatalities in 2015; as a result, globally, it is the greatest cause of mortality in children under the age of five. The neonatal phase is when preterm infants are most at risk for serious illness or death. Those who survive are more likely to have a poor quality of life and a lifelong impairment without the proper care. Here, we have the Introduction to Preterm birth it’s Causes, signs and prevention topic given in this blog.

Pathophysiology of preterm birth:

Causes of preterm birth are complex and the pathophysiology that triggers preterm birth is largely unknown, however, contributing maternal, fetal, and placental predisposing factors have been identified.

  • The most common of these include
  • Antepartum hemorrhage or abruption
  • Mechanical factors such as uterine over-distention and cervical incompetence
  • Hormonal changes
  • Bacterial infection and inflammation
  • Some of the studies also show risk factors such as maternal age being less than 17 years and more than 35 years, being underweight/overweight pre-pregnancy body mass index.

The availability of assisted reproductive technology (ART) in many high-income nations during the past 20 years has led to an increase in multiple births and overall premature delivery rates. Preterm births from spontaneous labor or premature rupture of the membranes (PROM), or from maternal illnesses such as pre-eclampsia or fetal abnormalities, are more common in children delivered from multiple pregnancies.

The following tables show the median birth weight, length and head circumference of premature babies at different gestational ages for each sex:

Photo Source Mayoclinic
Photo Source Mayoclinic

You may also be interested in the State of Inequality in the World Reproductive Maternal Newborn and Child Health

Warning signs of preterm labor (CDC)

Preterm labor (labor that starts too soon, before 37 weeks of pregnancy) typically starts suddenly and without apparent explanation. Similar to early labor, these are early labor signs:

  • Contractions (the abdomen tightens like a fist) every 10 minutes or more often
  • Change in vaginal discharge ( a significant increase in the amount of discharge or leaking fluid or bleeding from the vagina)
  • Pelvic pressure-the feeling that the baby is pushing down
  • Cramps that feel like a menstrual period
  • Abdominal cramps with or without diarrhea


Premature babies are more likely to die and experience a range of health and developmental issues than babies delivered at term. Acute respiratory, gastrointestinal, immune, nervous system, hearing, and vision issues are among the complications, as are long-term issues with movement, cognition, vision, hearing, behavior, social-emotional health, and development. Preterm delivery can have an impact on public-sector services including health insurance, education, and other social support networks, as well as significant emotional and financial consequences to families. Preterm birth is a complicated collection of issues with a number of overlapping influences. Its reasons might include biological variables, genetics, neighborhood traits, environmental exposures, medical issues, infertility treatments, and individual-level behavioral and psychological aspects. Especially in people who are socioeconomically disadvantaged or who belong to racial or ethnic minority groups, several of these characteristics coexist in combination.


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  5. Cite this Page
  6. National Guideline Alliance (UK). Preterm labour and birth: [A] Evidence review for clinical effectiveness of prophylactic progesterone in preventing preterm labour. London: National Institute for Health and Care Excellence (NICE);