Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OBSTETRICS AND GYNAECOLOGY COPY > MULTIPLE PREGNANCY > Flashcards

MULTIPLE PREGNANCY Flashcards

1
Q

What is the incidence of twin pregnancy?

A

1 in 80 pregnancies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the incidence of spontaneous triplets?

A

1 in 6400 pregnancies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What factors increase the likelihood of having a multiple pregnancy?

A

Increasing maternal age

Increasing parity

More common in African

Improved nutrition

Assisted conception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How and when are multiple pregnancies usually diagnosed?

A

Routine dating ultrasound scan at 11-14 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What percentage of twins are dizygotic?

A

75%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the most important clinical issue to work out on discovery of twins?

A

The chorionicity of the pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is chorionicity?

A

How many placenta there are for the twins - ie whether they are sharing or not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the risk of monochorionic twins?

A

Unequal distribution of blood leading to growth restriction of one twin and macrosomia in the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Are monochorionic twins always monozygotic?

A

Yes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Are monozygotic twins always monochorionic?

A

No. It depends at what stage in cell replication the split occurs.

1/3 happen in the 8 cell stage and these twins will be dichorionic, like dizygotic twins.

2/3 happen days 3-8 and are therefore monochorionic but diamniotic, as the inner mass splits to form two seperate membranes.

A small proportion happen between days 8-13 and are therefore monochorionic monoamniotic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Are most triplets monozygotic or trizygotic?

A

Neither. Most triplets come from originally two fertilised ova, where one of them splits to form monozygotic twins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do work out the chorionicity antenatally?

A

USS before 16 weeks gestation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the name of the sign seen on USS in dichorionic twins?

A

Lambda

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the name of the sign seen on USS in monochorionic diamniotic twins?

A

T sign

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How might you work out the zygosity of twins on USS?

A

Chorionicity

Different sexs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the risks and complications of multiple pregnancies?

A

Increased risk of any complication associated with singleton pregnancy - gestational diabetes; pre-eclampsia or pregnancy induced hypertension

Increased chance of fetal malformation

Intrauterine growth restriction (IUGR)

Preterm labour

Increased chance of antepartum haemorrhage (placenta abruption and praevia)

Twin-to-twin transfusion syndrome

Increased chance of postpartum haemorrhage

Locked twins

17
Q

What is the problem of finding fetal abnormalities in only one of the two twins?

A

Selective fetocide can result in the miscarriage of the apparently normal fetus as well as the abnormal one.

18
Q

How should antenatal care be increased in mothers with multiple pregnancy?

A

Serial USS every 2 to 4 weeks to exclude IUGR - especially important with monochorionic placentation.

19
Q

In what proportion of multiple pregnancies does preterm labour occur?

A

30%

20
Q

What can be used as a screening tool to work out likelihood of preterm labour in a woman with multiple pregnancy?

A

Cervical length screening by transvaginal ultrasound

21
Q

How might preterm labour be prevented in higher order multiple pregnancies?

A

Elective cervical suture at the start of the second trimester

22
Q

How do you manage a woman with multiple pregnancy who goes into preterm labour?

A

Tocolytics to allow time for steroids to be given to improve lung maturation.

23
Q

How much more common is pregnancy related hypertension in multiple pregnant women than singleton women?

A

3 times

24
Q

Why is pregnancy-induced hypertension so much more common in multiple pregnancy?

A

Larger size of the placental bed

25
Q

What is twin-to-twin syndrome?

A

Blood is shunted across fetal vascular anastomoses, such that the donor becomes anaemic and growth restricted, with oligohydramnios and the recipient becomes fluid overloaded with polyhydramnios.

26
Q

What is the incidence of twin-to-twin syndrome in monochorionic diamniotic twins?

A

15%

27
Q

When does twin-to-twin syndrome usually occur?

A

In the second trimester

28
Q

What is the risk of fetal death in untreated twin-to-twin syndrome?

A

80%

29
Q

What is the risk of handicap in the surviving twin in twin-to-twin syndrome?

A

10%

30
Q

How do we manage twin-to-twin syndrome?

A

Laser treatment to placental anastomoses (FLAP - fetoscopic laser ablation of the placenta)

Amniodrainage may be appropriate at later gestation

31
Q

What are the complications of a scenario where one fetus of a set of monochorionic twins has died and how do we manage this?

A

Puts surviving twin at risk of neurological damage

Puts mother at risk of DIC as thromboplastins are released into the circulation.

Pregnancy can be managed conservatively until surviving twin reaches a gestation with improved likelihood of survival. 80% of surviving twins can be delivered vaginally

32
Q

How is the delivery of multiple pregnancy managed?

A

Neonatal unit intensive care facilities

Allow vaginal delivery if normal pregnancy and twin 1 cephalic presentation

IV access / FBC / G+S

Regional anaesthesia - to allow for more manipulation

Continuous CTG monitoring

Fetal scalp electrode to twin 1

IV syntocinon infusion to start after delivery of twin 1

ECV can be used if twin 2 not in longitudinal presentation

IV syntocinon infusion to continue for third stage to reduce PPH

33
Q

If twin 1 is not in cephalic presentation at labour, how is delivery of multiple pregnancy managed?

A

Normally c-section

34
Q

How do we manage higher order multiple pregnancies?

A

Nearly always c-section

35
Q

What is locked twins?

A

Rare complication of vaginal deliveries when first twin is in breech. Aftercoming head of twin 1 is prevented from entering pelvis by head of cephalic presenting twin 2.

36
Q

How do we manage locked twins?

A

If first stage of labour: c-section

If second stage of labour: general anaesthesia to allow necessary manipulation

37
Q

What is selective fetocide and why is it done in higher order multiple pregnancies?

A

Intracardiac potassium chloride given to one or more fetuses under ultrasound guidance to improve outcome of remaining fetuses.

38
Q

When is selective fetocide usually performed?

A

11-14 weeks

39
Q

What is the procedure-related risk of miscarriage in selective fetocide?

A

6%

OBSTETRICS AND GYNAECOLOGY COPY (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions