POSTTERM PREGNANCY Dr Mona Shroff Dept of OG

POST-TERM PREGNANCY Dr. Mona Shroff (Dept. of O&G. SMIMER)

DEFINITION l POSTTERM: (>294 d) l POST >42 completed weeks DATE: >40 completed weeks(280 d) MATURITY: Specific syndrome of infant associated with postterm preg

INCIDENCE l BY LMP : 7. 5 % l BY USG : 2. 6 % l BY LMP + USG : 1. 1 % l Previous 1 postterm : 27 % l Previous 2 postterm : 39 %

AETIOLOGY l Wrong dates l Biological-previous prolonged preg. l Irregular ovulation l Decreased fetal estrogen production Placental sulfatase deficiency Anencephaly Fetal adrenal hypoplasia l Extrauterine preg (v. rare)

PHYSILOGICAL CHANGES ASS. WITH POSTTERM GESTATION l PLACENTAL CHANGES : senescence/ageing (increased grading on usg) infarcts, calcification AMNIOTIC FLUID CHANGES : Oligohydramnios (diminished fetal urination) cloudy (flakes of vernix) L/S ratio => 4: 1 presence of meconium l FETAL CHANGES : 45%-Macrosomia 10%-IU malnutrition l

COMPLICATIONS l l MATERNAL Anxiety Traumatic vaginal delivery-shoulder dystocia Increased CS rate PPH risk l l l FETAL Fetal distress MAS Fetal trauma brachial plexus injuries, clavicle fracture Increased perinatal mortality Dysmaturity syndrome

MANAGEMENT CONFIRMATION OF GESTATIONAL AGE 1. Reliable LMP Date known No OCP for 3 mnths Regular cycles 2. First trimester CRL(+/-7 d) 3. Second trimester BPD (+/- 14 d) 4. First trimester P/V examination 5. Doppler FHT 10 wks 6. Quickening 16 -18 wks

l USG AFI <5 oligohydramnios Macrosomia Placental grading l P/V examination Assess inducibility-BISHOPS score

Identification of patients that need delivery Ripe cervix Oligohydramnios Macrosomia Abnormal NST/BPP/CST Meconium stained liquor DELIVERY Unripe cx Normal fluid Normal NST/CST Normal fetal size Cervical assessment, NST, AFI Weekly at 40 & 41 wks Twice wkly thereafter Ripe cx Oligo Abn NST 42 WKS DELIVERY

INTRAPARTUM MANAGEMENT l Left lateral position l Continuous electronic fetal monitoring l Early ARM in active phase (hastens progress, detects meconium) l LSCS if CPD/macrosomia, fetal distress l Amnioinfusion (750 -1000 ml NS/RL) –If meconium stained liquor, variable deccelerations l Paediatrician called at delivery

PREVENTION Sweeping/stripping of membranes at term if no vaginitis, malpresentation or placenta praevia