Chapter 32 Labor and Birth Complications

OB test 3

preterm labor (PTL)

regular contractions along with a change in cervical effacement or dilation or both or presentation with regular uterine contractions and cervical dilation of at least 2 cm

preterm birth

any birth that occurs between 20 weeks and 36 weeks & 6 days of gestation; birth is before completion of 37 weeks

very preterm

less than 32 weeks of gestation

moderately preterm

between 32-34 weeks of gestation

late preterm

34wks-36wks & 6 days of gestation

low birth weight

less than or equal to 2500g at birth (5.5lbs)

factors that influence survival rates of infants born premature

fetal number (single vs multiples), sex, use of antenatal corticosteroids and birth weight

what causes decreased uteroplacental perfusion?

hypertension and smoking

why is preterm birth more dangerous than low birth weight?

preterm birth is the length of gestation regardless of birth weight; it is more dangerous than birth weight alone because less time in the uterus correlates with immaturity of body systems

what are some potential causes of low birth weight?

preterm birth, IUGR or decreased uteroplacental perfusion

spontaneous preterm birth

preterm birth occurs following an early initiation of the labor process in the apparent absence of maternal or fetal illness

what is the only definitive factor for the cause of spontaneous preterm birth?

INFECTIONS!!! (genital tract infections, appendicitis, any type of infection)

what are other causes of spontaneous preterm birth?

placental causes, maternal and fetal stress, uterine overdistention, congenital structural abnormalities of the uterus, history of previous preterm birth or due to decrease in progesterone

indicated preterm birth

preterm birth occurs as a means to resolve maternal or fetal risk related to continuing the pregnancy

what are causes of indicated preterm birth?

gestational diabetes, preeclampsia or chronic HTN, previous c-section birth with a classical incision, seizures and thromboembolism