Final-Fundal Height Abnormalities Flashcards
How do you measure fundal height?
Woman supine w/ straight legs
Empty bladder
Measure from top of symphysis pubis to top of fundus (level of xyphoid process)
Relationship of fundal height with weeks gestation
10-20 weeks: nonpalpable to ~20cm by 20 weeks
20-30 weeks: fundal height about equal to her weeks
20-36 weeks: uterus grows ~3.5cm/month
30-43 weeks: uterine growth slows so she is between 38-40cm by term
DDx Increased Fundal Height
- wrong EDD
- multiple gestation
- macrosomia
- polyhydramios
- hydatiform mole
- obesity or ascites
- uterine, abdominal or adnexal mass
- idiopathic
DDX Decreased Fundal Height
- wrong EDD
- oligohydramnios
- IUGR
- transverse presentation
- idiopathic
EDD
LMP + 280 days = EDD
Factors that effect accuracy of EDD calculation
- irregular cycles
- long cycles
- unknown LMP
- have a period during 1st month of pregnancy
When can you detect fetal heart tone with doppler?
10-12 weeks from LMP
Ultrasound and EDD
very accurate before 20 weeks, gives due date +/- 5 days
Early US around 10-12 weeks can give +/- 2 or 3 days
Multiple Gestation Types
- Identical (monozygotic, monovular)
- Fraternal (dizygotic, binovular)
- Triplets
Identical twins
1 ovum fertilized by one sperm, separates early in development into 2 or more embryos
incomplete separation results in conjoined twins
placentas usu fused w/ 2 umbilical cord, 2 amnions, 1 chorion
Greater incidence of congenital abnormalities in fraternal or identical twins?
Identical
Fraternal twins
2 or more ova fertilized by 2 or more sperm with normal division
placentas sometimes fuse, 2 chorions and 2 amnions
Factors influencing fraternal twins
- increased use of fertility agents like Clomid, Perganol (stimulate ovary to release eggs)
- increased usage of in-vitro fertilization
- possible cocaine use
Triplets
most often associated with fertility agents and in-vitro fertilization
Maternal risks of multiple gestation
- Hyperemesis
- Pressure sxs: varicose veins, hemorrhoids, dyspnea, heartburn
- Anemia
- Preeclampsia
- Polyhydramnios
- Post partum hemorrhage
Fetal risks of multiple gestation
- placenta previa
- placental abruptions either prenatally or in labor and delivery
- prematurity due to premature labor or early induction
- PROM
- prolapsed cord
- malpresentation or entanglements
- low birth weight or IUGR
- malformations
- fetal to fetal transfusions
- Death
Dx of multiple gestation: History
- increased incidence w/ multiple births in mom’s family or mom is a twin
- age >35 y/o
- increased parity
- use of infertility drugs or in-vitro fertilization
Dx of multiple gestation: sxs
- excessive vomiting
2. rapid weight gain
Dx of multiple gestation: signs
- large fundal height (usu apparent by 28-32 weeks)
- difficult interpretation of fetal parts
- may detect 2 different fetal heart tones w/ 2 different dopplers
Definitive dx of multiple gestation
US!
Triple Test
Multiple gestation test where mom may have increased bHCG, HPL, estriol
Prenatal management of multiple gestation
- increased nutrition
2. possible bedrest to prolong pregnancy
Criteria for possible hospital vaginal birth w/ multiple gestation
- multip
- vertex presentations
- no other complications
- otherwise often pre-term C-section
Macrosomia definition
Large for gestational age
>90% greater than 9lb
Macrosomia etiology
- Gestational diabetes or DM
- maternal obesity or excess weight gain
- post-term pregnancy
- large parental size or family hx of macrosomia
- erythroblastosis fetalis
Macrosomia dx
- palpate large fetus abdominally
- large fundal height (greater than 38 cm)
- US is concerning if: fetus >9lbs, biparietal diameter >10cm, biparietal diameter or abdominal circumference equal to 44 week fetus at term
Risks of macrosomia
- Cephalopelvic disproportion (CPD) leading to C-section
- Shoulder dystocia
- Birth injuries due to instrumentation or broken clavicles
- idiopathic respiratory distress
- hypoglycemia
- hypocalcemia
- congenital abnormalities
Polyhydramnios definition
Excess amniotic fluid (greater than 2000 ml)
Etiology of polyhydramnios
- acute polyhydramnios: usu w/ identical twins in 2nd trimester
- chronic polyhydramnios: idiopathic 50%
- congenital anomalies
- failure of fetus to swallow: CNS defects from infxn, fetal hydrops, extended head (anencephaly)
- Maternal dz
Fetal hydrops
Excess fluid in fetus usu secondary to hemolytic anemia
Clinical presentation of polyhydramnios
- rapid increase in abdominal size and fundal height appearing large for dates
- rapid weight gain
- fetus difficult to palpate
- tense uterus
- difficult auscultation of FHT
Polyhydramnios dx
- 4 quadrant sum via US
- EHS-greater than 23
- emanuel 20-25 borderline; 25 definite polyhydramnios
Management of polyhydramnios
- US for dx and to r/o most congenital anomalies and check cord location
- Lab: glucose screen, ab screen if Rh neg, TORCH panel to r/o infxn
- If fetus normal on US, lab normal, polyhydramnios borderline and cord not over head consider OOH birth
- If criteria not met, refer for hospital birth
Perinatal risks of polyhydramnios
- perinatal mortality for non-idiopathic cases is 50%
- congenital anomalies
- premature labor
- prolapsed cord with ROM
- placental abruption
- dysfunctional labor due to over distended uterus
Maternal risks of polyhydramnios
- post partum hemmorhage due to uterine atony from over distended uterus
- severe dyspnea
- varicose veins and hemorrhoids
Oligohydramnios definition
Too little amniotic fluid (less than 200ml)
Oligohydramnios etiology
- Idiopathic
- palcental failure associated with IUGR and placental insufficiency
- Fetal malformation: renal agenesis, lower UTI obstructions
Oligohydramnios clinical presentation
- low fundal height
2. fetal parts very easily palpated
Oligohydramnios dx
- less than 5 on a 4-quadrant sum via US
2. also gives placental grade, biophysical profile and checks for some anomalies of urinary tract
Management of oligohydramnios before 37 weeks
Watch fetus carefully with daily fetal movement counts and repeat biophysical profiles and/or NST every 1-2 weeks
Management of oligohydramnios from 37-40 weeks
continue close fetal surveillance and consider natural induction
Management of oligohydramnios from 40+ weeks
Immediate natural induction & if unsuccessful do not wait long to refer to pitocin
Risks of oligohydramnios
- IUGR from prenatal hypoxia
- Fetal hypoxia in labor
- Urinary tract malformations
- Amniotic bands causing abnormal contractions in labor
- cramping deformities
IUGR definition
Less than 10th percentile of weight for gestational age
IUGR weight categories
- 5 lb at 38 weeks
- 5.6 lb at 40 weeks
- 6 lb at 42 weeks
Asymmetric IUGR
- Relatively normal head size and body length w/ abormal weight and soft tissue mass
- usu due to problem in 2nd or 3rd trimester
- 80% of IUGR
- better prognosis
Symmetric IUGR
- proportionately small all over for gestational age
- usu due to problem in 1st or early 2nd trimester
- 20% of IUGR
- poor prognosis
Mortality of IUGR
- twice that of well grown mature baby
- half that of preterm baby
- death most likely during last 2-3 weeks of pregnancy usu due to placental malfunction
IUGR increases the risk of..
- perinatal asphyxia
- congenital malformations
- fetal infxns
- post natal polycythemia
- post natal hypoglycemia (2/3 of IUGR)
- long term learning disabilities
What percentage of IUGR is idiopathic?
33%
IUGR Etiologies: fetal
- chromosomal disorders
- chronic fetal infxn
- congenital abnormalities
IURG etiologies: placental
- small placenta
- infarcted placenta
- abrupted placenta
- premature calcification of placenta
- choriohemangiomas
- villitis
- placenta previa
IUGR etiologies: maternal
- Hypertension: 35%
- Chronic dz
- Malnutrition, usu w/ inadequate weight gain
- chemical addiction
- hemoglobinopathies
- ethnic/familial/small stature of mom
- multiparity
- less than 15 y/o
- environmental: high altitude, heavy radiation exposure
IUGR clinical presentation
- fundal height drops below 10th percentile on fundal height growth chart OR
- fundal height stays the same over 2-4 weeks
- lack of or decreased rate of weight gain
US dx of IUGR
head vs. abdomen and head vs. femur length is assessed most often
-Dx made much easier with accurate early EDD
Prevention of IUGR
Good nutrition and prenatal supplementation
No smoking, drugs or alohol
Management of IUGR: Lifestyle changes
- cease working
- stress management/counseling
- rest in left lateral recumbent position to increase fetal oxygenation
- no sexual intercourse
- ensure good nutrition and caloric intake, carbs & protein
- cessation of smoking, drugs, alcohol and caffeine
Management of IUGR: Lab
- TORCH panel
- consider amniocentesis
- watch for signs of maternal dz
- monitor fetal well being
- refer appropriately
- labor often induced early
