CHAPTER 8 - ASSESSMENT OF FETAL GROWTH AND DEVELOPMENT

Question 1

Fetal period begins; crown-rump length 5 cm; weight 8 g

Answer 1

9 weeks

Question 2

External genitalia are distinguishable

Answer 2

12 weeks

Question 3

First missed menstrual period; mesoderm appears (trilaminar embryo); somites begin to form

Answer 3

3 weeks

Question 4

Eyelids begin; crown-rump length is 2 cm

Answer 4

7 weeks

Question 5

Lens placode; primitive mouth, digital rays on hands

Answer 5

5 weeks

Question 6

Fertilization and implantation; beginning of embryonic period

Answer 6

1 week

Question 7

Bilaminar embryo; endoderm and ectoderm appear

Answer 7

2 weeks

Question 8

Term

Answer 8

38 weeks

Question 9

Eyes open; fetus turns head down; weight 1,000-1,300 g

Answer 9

28 weeks

Question 10

Usual lower limit of viability; weight 460 g; length 19 cm

Answer 10

20 weeks

Question 11

Third trimester begins; weight 900 g; length 24 cm

Answer 11

25 weeks

Question 12

Ovaries and testes distinguishable

Answer 12

8 weeks

Question 13

Primitive nose, philtrum, primary palate

Answer 13

6 weeks

Question 14

Neural folds fuse; folding of embryo into human-like shape; arm and leg buds appear; crown-rump length 4-5 mm

Answer 14

4 weeks