measurements & dates for obgyn

The graafian follicle will measure __-__ mm.

15-30 mm

How thick is the endometrium during menses?

1-4 mm

How thick is the endometrium during proliferative?

4-8 mm

How thick is the endometrium during secretory?

8-16 mm

How long is the average menstrual cycle?

28 days

FSH will be released on days…

1-13

LH will be released on day…

14

When does the follicular phase occur?

Days 1-13

What day does ovulation occur on?

14

When does the luteal phase occur?

Days 15-28

When does the menses phase occur?

Days 1-5

When does the proliferative phase occur?

Days 6-14

When does the secretory phase occur?

Days 15-28

How large would the vaginal cuff typically measure?

Less than 2 cm AP

How large is a Nabothian cyst typically?

Less than 2 cm

A premenarche patient has a uterine length up to…

3-4 cm

A menarche patient has a uterine length up to…

6-8 cm

A postmenopausal patient has a uterine length up to…

4-6 cm

After giving birth, the uterine length can increase by approximately __ cm per child.

1 cm

A menarche patient has an ovarian length up to…

3-3.5 cm

A postmenopausal patient has an ovarian length up to…

2 cm

What is the ovarian volume range for a premenarche patient?

3-8 cm³

What is the ovarian volume range for a menarche patient?

9.8-22 cm³

What is the ovarian volume range for a postmenopausal patient?

5.8-8 cm³

What is the endometrium thickness for a postmenopausal patient not on HRT?

Less than 5 mm

What is the endometrium thickness for a postmenopausal patient on HRT or tamoxifen?

Up to 8 mm

Women who take a continuous/combined form of estrogen and progesterone have an endometrium that measures what?

Less than 8 mm

Small echogenic foci seen in the ovaries are not considered significant if they measure between…

1-3 mm

Cumulus oophorus will measure less than…

1 mm

Varicose veins with pelvic congestion syndrome will measure greater than…

5 mm

The graafian follicle can become how large by the time of ovulation?

2-2.5 cm

The graafian follicle will normally measure…

1.5-3 cm

1. Post menopausal cysts will measure less than…

2. But a cyst less than… should be followed

1. 3 cm

2. 5 cm

A simple cyst in the ovary than is less than __ cm is considered within normal limits.

3 cm

A cyst in the ovary that is greater than __ cm will require surgical intervention or aspiration.

5 cm

The corpus luteum can typically measure between __-__ cm.

1-10 cm

An ovarian dermoid can measure as large as __ cm.

40 cm

1. Cervical incompetence will show a cervical length less than __ mm.

2. OR a dilation of the cervix greater than __ mm at the internal os.

1. 25 mm

2. 25 mm

The gestational sac and embryo can grow up to __ mm per day.

1 mm

1. How can gestational age be calculated in days?

2. How about in weeks?

1. MSD (mm) + 30 = GA in days

2. Divide by 7

How is gestational age calculated in days with CRL?

CRL (mm) +42 = GA in days

When does the embryonic period end?

Week 10

When does the fetal period begin?

Week 10

Until what week should CRL be taken?

Week 12

The CRL can be obtained as early as what week TV?

Week 5.5

During the 2nd and 3rd trimester, AFI should be measured after what week?

Week 24

During the 2nd and 3rd trimester, anatomic survey should be measured after what week?

Week 18-22

The femoral diaphysis length can be reliably used after how many weeks?

14 weeks

The yolk sac should be visualized when the MSD is greater than __ mm TA.

20 mm

The yolk sac should be visualized when the MSD is greater than __ mm TV.

8-10 mm

A nuchal translucency greater than __ mm may be found with trisomy 13, 18, 21; cardiac defects; and genetic syndromes.

3 mm

All major internal and external fetal structures develop by what week?

Week 10

What weeks make up the first trimester?

0-12

What weeks make up the second trimester?

13-28

What weeks make up the third trimester?

29-40

1. Normal hCG levels double every __-__ days.

2. It will do this until week __-__.

1. 2-3

2. 9-10

The yolk sac can be visualized at what week?

Week 5

By what week is yolk sac reabsorbed and no longer seen on US?

Week 12

At what week will the amnion and chorion fuse?

Week 16

The double bleb sign is typically visualized around what weeks?

Week 5-7

The first initial heart beat and endocardial fused tubes will be seen at __-__ weeks.

5 ½ - 6 weeks

When is the rhombencephalon seen?

Week 8-11

The bowel migrates into the base of the umbilical cord at what week?

Week 8-12

The midgut returns to the abdominal cavity by week…

Week 12

The limb buds may be detected from week…

Week 7

The developing sign is first visualized at week…

Week 6

1. What week should the fetus be at to measure the nuchal translucency?

2. What should CRL measure?

1. Week 11-13

2. 45-84 mm

What is the formula for Naegele’s rule?

EDD = LMP- 3 months + 7 days + 1 year

Retained products of conception will have a thickened endometrium measuring greater than __-__ mm.

8-10 mm

An anembryonic pregnancy is diagnosed when the gestational sac is greater than __ mm.

25 mm

An interstitial ectopic pregnancy will have a myometrium measuring less than __ mm surrounding the gestational sac.

5 mm

A threatened abortion is experiencing a bleed __ weeks before pregnancy.

20 weeks

What finding would rule out an ectopic pregnancy?

Doubled hCG every 2-3 days

What is the normal lateral ventricle measurement?

6.5 mm

If the posterior portion (atrium) of the lateral ventricle measures greater than __ mm, the fetus would need further evaluation.

10 mm

A normal cisterna magna should measure greater than (1)__ mm, but less than (2)__ mm.

1. 3 mm

2. 10 mm

A normal nuchal fold is less than (1)__ mm between (2)__-__ weeks.

1. 6 mm

2. 18-22

A nuchal fold greater than __ mm has shown an association with trisomy 21 and other syndromes.

6 mm

What is the measurements for a mildly abnormal renal pelvis at 16-27 weeks?

4-7 mm

What is the measurements for a moderately abnormal renal pelvis at 16-27 weeks?

7-10 mm

What is the measurements for a severely abnormal renal pelvis at 16-27 weeks?

Greater than 10 mm

What is the measurements for a mildly abnormal renal pelvis greater than 28 weeks?

7-9 mm

What is the measurements for a moderately abnormal renal pelvis greater than 28 weeks?

9-15 mm

What is the measurements for a severely abnormal renal pelvis greater than 28 weeks?

Greater than 15 mm

The neural tube should be completely closed by __ weeks.

6 weeks

Measurement of the cerebellum equals gestational age until about __ weeks.

23 weeks

1. The nuchal fold can be measured between __-__ weeks.

2. Some experts say you can measure it between __-__ weeks.

1. 18-22

2. 14-24

At what week of gestation can the gallbladder be seen?

Week 20

1. The stomach can be visualized by __ weeks gestation.

2. BUT it should always be seen by __ weeks gestation.

1. 13

2. 16

The fetal abdominal wall can be evaluated after weeks __-__.

12-14

The kidneys are developed by week…

9

1. The kidneys will start to be visible around __-__ weeks.

2. BUT they will consistently be seen after __ weeks.

1. 13-15

2. 20

The bladder should be seen by week…

Week 16

The proximal humerus epiphysis is seen at __-__ weeks.

38-39

The proximal tibial epiphysis is seen at __ weeks.

35

The distal femoral epiphysis is seen at __ weeks.

33

The CNS arises from the neural plate at __ gestational days.

18

The CNS at around __-__ gestational days will have neural folds growing towards each other.

24-26

1. A score of 2 is given for amniotic fluid when the largest vertical pocket measures at least __ cm.

2. OR when amniotic fluid measures __-__ cm.

1. 2 cm

2. 5-22 cm

Oligohydramnios correlates with an AFI less than…

5 cm