2025 – PAGE 93 – OB/GYN AND SOME STDs

BIOPHYSICAL PROFILE (BPP)

A Biophysical Profile refers to an ultrasound that is done to check breathing, tone, movement, amniotic fluid, and heart rate.

STRESS TEST (AKA CONTRACTION STRESS TEST)

A contraction stress test evaluates fetal response to contractions. It assesses the fetus for uteroplacental insufficiency and tolerance of labor.

MNEMONIC: Contractions are STRESSFUL!

FOLIC ACID

All women of childbearing age should consume 0.4 mg (400 mcg) of folic acid per day. If a woman has already had a child with a neural tube defect and is now planning on becoming pregnant, she should consume 4 mg of folic acid per day starting 1 month before trying to get pregnant.

LUNG MATURITY

• ­PHOSPHATIDYLGLYCEROLis the best predictor of fetal lung maturity. Why? Because it’s not made until after the 35^th week of gestation.
• ­LECITHIN-SPHINGOMYELINRATIO: An L/S ratio > 2 (from the amniotic fluid) indicates fetal lung maturity.

MONOZYGOTIC TWINS

In monozygotic twins, one zygote splits into two, so they must be identical twins. There can be ONE or TWO amniotic sacs, and the twins can share ONE placenta, or they can have TWO (one for each).

• ­MONOAMNIOTIC = 1 Amniotic sac is contained in the uterus and houses both twins
• ­DIAMNIOTIC = 2 Amniotic sacs are contained in the uterus, each housing one twin
• ­MONOCHORIONIC = 1 Placenta in the uterus supports both twins
• ­DICHORIONIC = 2 Placentas are in the uterus, one for each twin
• ­PEARL/SHORTCUT: The one permutation that is NOT POSSIBLE is MONOAMNIOTIC/DICHORIONIC. So, just remember that if both twins are in ONE amniotic sac, they will share ONE placenta. All other com­bi­na­tions are possible.

• ­PEARL: Confused? Break down the words, and you’ll be fine (Zygotic, Amniotic, Chorionic).