Jan Charmaine Almonte-Saret M.D., FPOGS, FPSUOG

equal or less than 13 weeks

Indications and advantages:- confirmation of intrauterine pregnancy/

early pregnancy failure- best estimation of G.A.- Evaluation of vaginal bleeding- Evaluation of ectopic pregnancy- Confirmation of multiple pregnancy- Evaluation of pelvic, ovarian or uterine

pathology

GUIDELINES FOR DATING PREGNANCYSTAGE OF DEVELOPMENT

GESTATIO-NAL AGE (WEEKS)

LEVEL OF B-HCG

Gestational sac 5 weeks 1,000-2,000 mIU/L

Gestational sac with yolk sac

5.5 weeks 7,200 mIU/L

Gestational sac with yolk sac & embryo

6 weeks 10,800 mIU/L

NUCHAL TRANSLUCENCY

11 to 14 wks =/> 3 mm Screening for fetal chromosomal

abnormalities screening for trisomy 21

NON-BIOMETRIC PARAMETERS

Uncertain of menstrual dates Measurement disparity in late trimester Narrow down error in estimation gestational

age

TRANSCEREBELLAR DIAMETER (TCD)- Numerically equivalent to the number of weeks

of gestation

NON-BIOMETRIC PARAMETERS

COLONIC GRADE• >/= 16 weeks- grade 1, anechoic lumen

• at 26 weeks & more- grade 2- lumen appears more echoic

• >/= 36 weeks- grade 3, lumen becomes brigther

DISTAL FEMORAL EPIPHYSES (DFE)• at least 32-33 weeks

PROXIMAL TIBIAL EPIPHYSES (PTE)• Seen at 35 weeks

PROXIMAL HUMERAL EPIPHYSES (PHE)

• at 38 weeks or more• reliable predictor of term gestation

SECOND & THIRD TRIMESTER

SIGNIFICANCE OF THE RATIOS

Cephalic Index (CI)-

BPD/OFD X 100 (74-83) > 83- brachycephaly –may suggest a

genetic abnormality < 74 – dolichocephaly – seen with

oilgohydramnios & breech presentation

FL/AC RATIO –evaluating skeletal dysplasia

- < 0.16 suggestive of a lethal type

HC/ AC RATIO- determines growth lag; high ratio –implies fetal malnutrition/IUGR

FL/BPD RATIO- can be used as one of the screening parameters for Down’s syndrome ( short femur & normal BPD= high ratio)

- Gold standard for antepartum fetal surveillance

WHEN TO REQUEST?-Antepartum testing started @ 26-28 weeks if

with maternal complications-@ 32-34 weeks for high risk patients

HOW FREQUENT? - Repeated weekly- Most authors suggest 2x/week BPS

&NST for:1. IDDM2. GDM with previous stillborn3. IUGR4. Post term pregnancy5. Preeclampsia

What are the signs of fetal hypoxia?Chronic Hypoxia (compensated)

1. Oligohydramnios2. Asymmetric (head-sparing) IUGR

Acute Hypoxia (non-compensated)1. Abnormal fetal heart rate changes

Non-reactive NST (+) CST

MODIFIED BPS-uses 2 parameters, NST ( acute marker of fetal compromise) & AFV (chronic marker)

BIOPHYSICALPARAMETER

CNS CENTER GESTATIONAL AGE

Fetal tone Cortex- subcortical area

7.5-8.5 wks

Fetal movement Cortex- nuclei 9 wks

Fetal breathing Ventral surface of 4th ventricle

20-21 wks

Fetal Heart Reactivity

Medulla & Posterior Hypothalamus

24-26 wks

Nueral Control of Fetal Biophysical Activities

Note: In pregnancy complicated by IUGR,

DOPPLER VELOCIMETRY studies will enhance the perfomance of BPS – changes in Doppler findings occur 4 days prior to the deterioration of BPS

A sonologic procedure to assess maternal A sonologic procedure to assess maternal

and fetal vascular resistance and fetal vascular resistance

(vasoconstricted/vasodilated) (vasoconstricted/vasodilated) the state the state

of fetal perfusion. of fetal perfusion.

To whom should we request it for? 1. Diabetes 2. Maternal HPN 3. Autoimmune Diseases - SLE, APAS,

Collagen vascular disease 4. Anemia 5. Post term Pregnancy 6. Unexplained Recurrent Pregnancy losses

7. Discordant multifetal pregnancy8. IUGR

UTERINE ARTERY WHAT ARE THE ABNORMAL RESULTS? Presence of notching Increase indices (SD, RI, PI)

AND IT’S SIGNIFICANCE?- Increase in the utero-placental resistance

(vasoconstriction)- Higher chance of pregnancy

complications

UMBILICAL ARTERY vasoconstriction

increase intraplacental resistance

elevated indices

decreased fetal perfusion fetal hypoxia then IUGR

ABSENT END DIASTOLIC FLOW (AEDF)

highest risk to develop adverse perinatal outcome

the mean duration from AEDF to onset of fetal distress is 6-8 days

REVERSED END DIASTOLIC FLOW (REDF)

most extreme form of intraplacental vascular resistance

diagnosis to distress interval 4.2 +/- 1.4 days with perinatal moratality rate of 50%

MIDDLE CEREBRAL ARTERYWhat is an abnormal result?

DECREASED INDICES- brain sparing reflex

Remember: fetal hypoxia induces compensatory

reflex preferential blood flow to the brain (MCA dilatation=decreased indices) while vasoconstriction in the less vital organs

NOTE: A sudden restoration of MCA indices to

normal or higher or increasing indices from a serial decreasing pattern is omninous= failure of the fetal cerebral vessels to vasodilate = acute fetal brain injury

Patients who are at high risk to develop abnormally adherent placenta includes:

Multiparity Hx of previous CS Hx of previous curettage Placenta previa implanted anteriorly in the

LUS

1. Unusually intense blood flow within the sonolucent space beneath the placenta

2. Hypervascularization within the placenta and non placental tissues

3. Turbulence of flow in areas where placentas appears to have lost parenchyma and within placenta lacunae

Should be done routinely in a 20-24 weeks gestation

Lowers perinatal mortality Lethal malformations-corrected early or

appropriate timing of delivery to allow surgical intervention; if not amenable to surgery, early counseling

ADVANTAGES OF TVS OVER TAS

1. Patient discomfort

2.Clearer images

3. Eliciting pain and tenderness

4.Earlier diagnosis of pelvic pathology

5. Good for obese patients and with abdominal scars

DISADVANTAGES OF TVS OVER TAS

1. Discomfort & pain to pxs with intact hymen and postmenopausal

2. Large pelvic masses 3. Refusal of the procedure

MENSTRUAL CYCLE

ENDOMETRIUM OVARY

Menstrual phase

Thin echogenic line

Developing follicles (5-10)

Early proliferative

Isoechoic Leading follicles

Late proliferative

Trilaminar Dominant follicles (18-24)

Secretory phase

Thick & Hyperechoic

Corpus luteum

Evaluates tubal patency primary investigative tool for infertility

When it is performed?First part of the menstrual cycle (Day 10-12)

advantage of eliminating the risk of X-ray

exposure & hypersensitivity to radiographic contrast media

Evaluation of endometrial pathology Evaluation of ovaries for follicular growth Evaluation of pelvic organs & structures for

lessions and masses