Stillbirth occurs when a baby dies after 20-28 weeks of pregnancy. Worldwide, 1.9 million stillbirths occurred in 2021. Most stillbirths occur in low- and middle-income countries. Rates have declined by 35% since 2000
Fetus is unborn mammalian offspring developing from embryo. Human fetal development begins 9 weeks after fertilization. Full-term fetus is between 37-40 weeks when sufficiently developed
Morning sickness affects 70-80% of pregnant women, with 60% experiencing vomiting. Symptoms typically occur between 4th and 16th weeks, subsiding by 20th week. About 10% of women continue symptoms after 20th week. Severe form (hyperemesis gravidarum) causes weight loss
Perinatal mortality refers to deaths of fetuses or neonates during first 28 days. WHO defines it as deaths per 1,000 births, starting at 22 weeks gestation. UK rate is about 8 per 1,000 births, highest in Asian women
Fertilization occurs when sperm fuses with egg cell in fallopian tubes. Zygote divides through mitosis into blastocyst, which implants in uterus. Gastrulation forms three germ layers: ectoderm, mesoderm, and endoderm. Neural plate folds into neural tube during fourth week
Uterus is pear-shaped organ located between rectum and bladder. Before pregnancy, uterus measures 3x2 inches, 1 inch thick, 1 ounce. By end of pregnancy, uterus can reach size of watermelon