Maternal Structure

Question 1

What four bones make up the female pelvis?

Answer 1

Sacrum, coccyx, and the 2 innominate bones

Question 2

What are the joints of the pelvis?

Answer 2

Symphysis pubis, sacrococcygeal, sacroiliac joints (2)

Question 3

What is significant about ischial spines?

Answer 3

• The ischial spines afford important evidence of the size of the pelvic outlet
• Spines of the ischium project medially into the pelvic cavity
• The imaginary line drawn from one ischial spine is used to assess how far the baby’s head has descended into the pelvis when examining vaginally

Question 4

What is the smallest diameter of the maternal pelvic outlet?

Answer 4

The transverse diameter

Question 5

What is the most common pelvis? Describe its features

Answer 5

Gynecoid
Best for child birth

Question 6

How many cms is the oblique aspect of the pelvic brim, cavity, and outlet?

Answer 6

12cm

Question 7

What is the largest diameter of the maternal pelvic outlet?

Answer 7

anteroposterior

Question 8

What is the smallest diameter of the maternal pelvic inlet?

Answer 8

anteroposterior

Question 9

What is the largest diameter of the maternal pelvic inlet?

Answer 9

Transverse

Question 10

What part of the pelvis is all the same measurement?

Answer 10

pelvic cavity (perfect circle)

Question 11

What angle within the pelvis is always 12cm?

Answer 11

The oblique

Question 12

What are the four pelvis shapes?

Answer 12

Gynaecoid, android, anthropoid, platypelloid

Question 13

Describe the android pelvis shape?

Answer 13

heart shaped, small inlet, least suitable for childbirth

Question 14

Describe the anthropoid pelvis shape?

Answer 14

Large, anteroposterior diameter larger than transverse

Question 15

Describe the platypelloid pelvis shape?

Answer 15

Flat oval shape, cavity is shallow, reduced anteroposterior diameter