- A A pregnancy that involves two separate fetuses developing simultaneously together in the uterus
- B Implantation of embryo outside the uterus (usually in fallopian tube); life-threatening as tube can rupture
- C An early miscarriage occurring within the first few weeks of gestation, before any implantation issue
- D A pregnancy that results mainly from in vitro fertilization treatment in some cases
Correct answer: B. Implantation of embryo outside the uterus (usually in fallopian tube); life-threatening as tube can rupture
Explanation: Ectopic pregnancy: implantation outside the uterus. Most common site: fallopian tube (tubal pregnancy, ~95%). Risk factors: previous pelvic inflammatory disease, STIs. Life-threatening because the tube ruptures as embryo grows, causing internal bleeding. Diagnosed by ultrasound and hCG levels.
Concept context
Male and female reproductive systems, gametogenesis, fertilization, implantation, pregnancy, and reproductive health.