tailieunhanh - Ebook Clinics in obstetrics: Part 2

Part 2 book “Clinics in obstetrics” has contents: Breech presentation, cardiac disease in pregnancy, pyrexia in pregnancy, postpartum hemorrhage, convulsions in pregnancy, RH negative pregnancy, thyroid disorders in pregnancy, jaundice in pregnancy, and other contents. | CHAPTER 12 Breech Presentation Tania G Singh DEFINITION • Defined as a fetus in a longitudinal lie with the buttocks or feet closest to the cervix (at the maternal pelvic outlet) • Commonest of all the malpresentations. INCIDENCE • • • • • • 3–4% of all deliveries Decreases with advancing gestational age: – 22–25% of births prior to 28 weeks gestation – 7% of births at 32 weeks gestation – 1–3% of births at term Fetal abnormalities are observed in: – 17% of preterm breech deliveries – 9% of term breech deliveries Cord prolapse occurs in: – 0–2% with frank breech – 5–10% with complete breech – 10–25% with footling breech – 6% in multigravidas – 3% in primigravidas Nuchal arms (one or both arms are wrapped around the back of the neck) are present in: – 0–5% of vaginal breech deliveries – 9% of breech extractions Fetal head entrapment (results from an incompletely dilated cervix and head that lacks time to mold to the maternal pelvis): – 0– of vaginal breech deliveries • Perinatal mortality: – Increased 2–4 fold with breech presentation, regardless of mode of delivery – Commonest causes: - Malformations - Prematurity - Intrauterine demise. 404 Section 1: Long Cases PREDISPOSING FACTORS • • • • • • • • • • • • • Prematurity (most common cause) Uterine malformations (septate; bicornuate uterus) Fibroids and cysts Polyhydramnios Oligohydramnios Placenta previa Cornual or fundal placement of placenta Fetal abnormalities (. CNS malformations—anencephaly, Down’s syndrome, hydrocephalus; myotonic dystrophy, neck masses, heart and GIT disorders) Multiple gestation Multiparity Breech presentation in the previous pregnancy Stretched and weakened uterine muscle Short umbilical cord. TYPES OF BREECHES • Frank or extended breech (50–70%)—Hips flexed, knees extended (pike position). Least associated with cord prolapse. Good dilator of the cervix • Flexed or complete breech (5–10%)—Hips flexed, knees flexed (cannon