Pregnancy Weeks & Timing – OB Exam Must-Knows

These flashcards cover essential facts and timelines related to pregnancy stages, fetal development, maternal changes, and key prenatal screenings.

Implantation

Occurs ~6 days after ovulation, marking the beginning of pregnancy.

Fetal heart tones (FHTs)

Detectable by Doppler around 6 weeks of pregnancy.

cfDNA screening

Can be performed around 10 weeks of gestation.

Quickening

The first noticeable movement of the fetus felt by the mother, typically around 20 weeks.

Viability

A fetus is considered viable at around 24 weeks gestation.

Braxton Hicks contractions

May begin around 14 weeks of pregnancy.

Fundus

The top of the uterus; reaches the level of the umbilicus around 20 weeks.

Gestational diabetes screening

Conducted between 24-28 weeks of pregnancy.

Neonatal period

The stage from birth to 28 days after delivery.

Teratogens

Substances that can cause defects during embryonic and fetal development, with the highest risk between days 15-60 (weeks 3-8).