Widespread Obstetric Procedures and Interventions in Maternal and Fetal Healthcare
OBSTETRICAL ULTRASOUND
Obstetrical ultrasound makes use of low-energy, high-frequency sound waves.
• Early first-trimester ultrasound makes use of a crown–rump (CRL) measurement.
• Later second- and third-trimester ultrasound makes use of 4 measurements: biparietal
diameter (BPD), head circumference (HC), stomach circumference (AC), and femur
size (FL).
Modalities
• Transvaginal sonogram is utilized in first trimester, producing high-resolution photographs
that aren’t influenced by maternal BMI. Relationship accuracy of early first-trimester
sonogram is +/- 5–7 days.
• Transabdominal sonogram is used any time in the course of the being pregnant, however picture high quality
could also be restricted by maternal weight problems. No hostile fetal results have been famous throughout
many years of analysis research. Relationship accuracy of early second trimester sonogram is
+/- 7–10 days.
• Doppler ultrasound research is used to evaluate umbilical artery (UA) and center cerebral
artery (MCA) blood stream. This modality assesses fetal well-being in IUGR pregnan-
cies, in addition to fetal anemia in alloimmunized pregnancies.
Indications
There are various causes to make use of obstetrical ultrasound.
• Being pregnant location & viability, gestational age relationship
• A number of gestation (zygosity, chorionicity, amnionicity)
• Amniotic fluid quantity (oligohydramnios, polyhydramnios)
• Fetal progress (IUGR, macrosomia)
• Fetal anomalies, fetal well-being
• Being pregnant bleeding, fetal anemia
Genetic Sonogram
Genetic sonogram, ideally carried out at 18–20 weeks, seems to be for anatomic markers of fetal
aneuploidy which embody:
• Generic: any structural abnormalities
• Particular: nuchal pores and skin fold thickness (strongest predictor), quick lengthy bones, pyelectasis,
echogenic intracardiac focus, hyperechoic bowel.
Nuchal Translucency
Nuchal translucency (NT) measurement is a screening take a look at carried out with sonogram
between 10–14 weeks, measuring the fetal fluid assortment behind the neck.
• A thickened NT will increase the probability of aneuploidy and cardiac illness.
• It’s mixed with two maternal blood assessments (free β-hCG & PAPP-A) in first-
trimester screening to extend the sensitivity and specificity for aneuploidy screening.
INVASIVE PROCEDURES
Chorionic Villus Sampling
Chorionic villus sampling (CVS) is a diagnostic outpatient workplace process carried out underneath
ultrasound (U/S) steerage with out anesthesia. Being pregnant loss fee is 0.7%.
• The catheter is positioned instantly into the placental tissue with out getting into the amniotic
cavity. Chorionic villi, that are placental precursors, are aspirated from a pregnant
uterus between 10 and 12 weeks’ gestation.
• The tissue is shipped to the laboratory for karyotyping. The chromosomes of the villi are
nearly at all times equivalent to these of the embryo.
• The process will be carried out both transcervically or transabdominally. Since
the fetus and chorionic villi are each derived from a standard origin (the zygote), their
karyotype is equivalent greater than 99% of the time.
Amniocentesis
Amniocentesis is a diagnostic, outpatient workplace process carried out after 15 weeks underneath U/S
steerage with out anesthesia. Being pregnant loss fee is 0.5%
• A needle is positioned right into a pocket of amniotic fluid underneath direct U/S steerage, aspirat-
ing amniotic fluid containing desquamated residing fetal cells (amniocytes).
• Fetal karyotyping is carried out on amniocytes. NTD (neural tube defect) screening is
carried out on amniotic fluid with biochemical evaluation (AFP and acetylcholinesterase).
Percutaneous Umbilical Blood Pattern (PUBS)
This transabdominal process, carried out underneath U/S steerage, aspirates fetal blood from the
umbilical vein after 20 weeks’ gestation. It may be diagnostic (e.g., blood gases, karyotype, IgG
and IgM antibodies) or therapeutic (e.g., intrauterine transfusion for fetal anemia). Being pregnant
loss fee is 1–2%.
Fetoscopy
A fetoscopy is a transabdominal process carried out with a fiberoptic scope within the working
room after 20 weeks underneath regional or basic anesthesia. Indications for fetoscopy embody
intrauterine surgical procedure or fetal pores and skin biopsy.
Laser is used for coagulating placental vessels in twin−twin transfusion syndrome (TTTS). Pores and skin
biopsy could also be carried out for suspected fetal ichthyosis. Dangers are bleeding, an infection, mem-
brane rupture, fetal loss. Being pregnant loss fee is 2−5%.
Cell-Free DNA
This can be a noninvasive screening process by which a maternal blood pattern is drawn after 9
weeks’ gestation.
• The take a look at measures small fragments of fetal/placental DNA in maternal blood to deter-
mine the chance of fetal aneuploidy.
• If the outcomes point out an elevated threat of abnormalities, a definitive take a look at ought to be
carried out, corresponding to chorionic villus sampling or amniocentesis.
