A 26-year-old woman presents to her obstetrician-gynecologist with a positive home pregnancy test. She is unsure of her last menstrual period (LMP) due to irregular cycles. She has experienced abdominal pain and vaginal bleeding for the last 3 days. Which of the following is an indication for performing a pelvic ultrasound to determine gestational age?
Jane, a 28-year-old woman, presents to her obstetrician-gynecologist with a positive home pregnancy test. She is unsure of her last menstrual period (LMP) due to irregular cycles. A pelvic ultrasound is performed to estimate the gestational age. Which measurement is considered the gold standard for estimating gestational age in the first trimester?
A 28-year-old woman presents for her first prenatal visit, uncertain about her last menstrual period (LMP) due to irregular cycles. She has a positive home pregnancy test and requests a pelvic ultrasound to determine gestational age. On examination, her uterus is consistent with early pregnancy, but fetal heart sounds are not audible with a Doppler device. The patient denies abdominal pain or bleeding. In which trimester is pelvic ultrasound the most accurate for determining gestational age?
A 32-year-old woman, G2P1, at 12 weeks gestation undergoes chorionic villus sampling (CVS) due to an increased risk of chromosomal abnormalities detected during her first-trimester ultrasound and screening tests. Findings: CVS Karyotype: Mosaic trisomy 16 in the placental sample, suggesting confined placental mosaicism (CPM). Amniocentesis: Fetal karyotype is normal (46,XX). Placental Tissue Analysis: Mosaicism for trisomy 21 confirmed. Which of the following outcomes is most likely in cases of confined placental mosaicism with a normal fetal karyotype?
A 35-year-old woman at 12 weeks gestation undergoes non-invasive prenatal testing (NIPT), which reveals a high risk for trisomy 21. Due to her advanced maternal age and abnormal NIPT result, she undergoes invasive prenatal testing. Findings: Amniocentesis: Fetal karyotype is normal (46,XX). Placental Tissue Analysis: Mosaicism for trisomy 21. What is a common maternal complication associated with confined placental mosaicism (CPM)?
A 32-year-old woman, gravida 2 para 1, at 12 weeks’ gestation is referred for chorionic villus sampling (CVS) due to an increased risk of chromosomal abnormalities noted during her first-trimester ultrasound and screening tests. She has no significant medical history and had a normal pregnancy with her first child. CVS Findings: Karyotype Results: Mosaic trisomy 16 detected in the placental sample. Interpretation: Confined placental mosaicism (CPM) suspected, but fetal involvement cannot be ruled out. What is the primary follow-up test to confirm whether the placental mosaicism detected on chorionic villus sampling (CVS) involves the fetus?
Which maternal serum marker is typically elevated in cases of neural tube defects such as spina bifida?
A 35-year-old woman presents for her first prenatal visit at 12 weeks gestation. She has a family history of Down syndrome, with her sister having a child with the condition. Given her advanced maternal age and family history, the patient is offered first-trimester screening for Down syndrome. The patient undergoes a combined screening test, which includes a nuchal translucency ultrasound and maternal serum screening for pregnancy-associated plasma protein-A (PAPP-A), inhibin-A, and free beta-human chorionic gonadotropin (β-hCG). Which combination of maternal serum markers is most commonly associated with Down syndrome (Trisomy 21)?
A 32-year-old pregnant woman (G2P1) presents for routine prenatal care at 17 weeks of gestation, confirmed by her last menstrual period and an earlier ultrasound. She has no significant medical or genetic history, and her first pregnancy was uncomplicated, resulting in the delivery of a healthy baby. Her family history is also unremarkable for genetic disorders or birth defects. During this visit, she undergoes a second-trimester maternal serum screening (quadruple screen) as part of routine prenatal care. The alpha-fetoprotein (AFP) level is above the 95th percentile. Which follow-up test can confirm the diagnosis of neural tube defects after elevated AFP in maternal serum screening?
