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Preterm Labor

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by Kohnle D

Risk Factors

The chance of preterm-labor is greatest in women under the 18 years or over 35 years. Other maternal factors that may increase the chance of preterm labor include:
Pregnancy complications that may increase your risk of preterm labor include:
  • Pre-eclampsia
  • Placental abruption
  • Premature rupture of the membranes
  • Carrying more than one baby
  • Vaginal bleeding after 16 weeks, or during more than one trimester
  • Infection in the cervix, uterus, vagina, or urinary tract including sexually transmitted diseases (STDs)
  • Being pregnant with a single fetus after in vitro fertilization (IVF)
  • Presence of a retained intrauterine device
  • Incompetent cervix
  • Too much or too little fluid surrounding the baby
  • Surgery on your abdomen during pregnancy
  • Amniotic fluid infection
  • Intrauterine fetal death
  • Intrauterine growth delay
  • Birth defects in the baby
Other factors associated with an increased chance of preterm labor include:
  • History of one or more spontaneous second-trimester abortions
  • Less than six months between giving birth and the beginning of the next pregnancy
  • A previous preterm birth
  • Uterine fibroids
  • Abnormally shaped uterus
  • Previous bariatric surgery
  • Procedures to remove abnormal cervical cells


Fluids in the cervix will also be tested for sign of labor progression. A tocometer may be placed to help monitor contractions.


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The American College of Obstetricians and Gynecologists



Health Canada

The Society of Obstetricians and Gynaecologists of Canada



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