Rubella In Pregnancy

Question 1

What is the incubation period for Rubella?

Answer 1

14 - 21 days

Question 2

For how long the patient is infectious in Rubella?

Answer 2

7 days before & 7 days after the onset of the rash

Question 3

How is Maternal rubella infection rash look like ?

Answer 3

Diffuse Maculopapular rash

Question 4

What are the infections characterized by maculopapular rash?

Answer 4

Rubella / measles / parvovirus B19

Question 5

What is the risk of vertical transmission of rubella at each period of pregnancy?

Answer 5

90 % before 12 w
55 % at 12 - 16 w
45 % after 16 w
Reinfection < 5 %

Question 6

What is the risk of congenital defects in rubella infected fetuses at each period of pregnancy?

Answer 6

90 % before 12 w
20 % 12 - 16 w

Question 7

Can reinfection with rubella be occur ?

Answer 7

Yes
Often subclinical / with vaccine induced rather than natural immunity
Risk to fetus is less than 5%

Question 8

What is the period of pregnancy that has a risk of deafness to fetus if maternal infection with rubella occurred?

Answer 8

Up to 20 weeks

Question 9

How is congenital rubella characterized?

Answer 9

1-Hearing loss
2-Learning disability
3-CARDIAC MALFORMATIONS ( don’t occur in CMV infection)
4- ocular defects ( cataract)
6- defects in CNS( microcephaly)
7- FGR
8- hepatospleenomegaly: jaundice, thrombocytopenia purpura, anemia
( petechiae)

Question 10

What are the late manifestations of congenital rubella?

Answer 10

Endocrinopathy, late onset deafness, ocular defects, neurodevelopmental problems

Question 11

How is rubella infection diagnosed?

Answer 11

1- seroconversion IgG
2- IgM+ve / IgG +ve with low IgG AVIDITY test
[ as with CMV - toxoplasma]

Question 12

According to maternal screening for the presence of rubella antibodies at booking , when to consider a woman susceptible to rubella infection?

Answer 12

If IgG < 10 iu/ml

Question 13

When rubella IgG,&IgM is detected?

Answer 13

IgM during 7 days of appearance of the rash : test must be repeated if negative and taken within 7 days
IgG 7 days after the onset of rash

Question 14

Can the diagnosis of acute rubella infection be made from rubella IgM?

Answer 14

With caution and with reference to:
History of rash
Exposure
History of vaccination

Question 15

If the pregnant has a history of exposure to rubella, and both IgM,IgG are negative, what is the management?

Answer 15

Repeat tests after 1 months
Consider 2 doses of MMR after pregnancy

Question 16

What is the management if rubella infection of the fetus is confirmed?

Answer 16

🚩Options include: termination of pregnancy, US to identify defects ( many features of congenital rubella aren’t detectable by US)
🚩- fetal echocardiography
- US for growth monitoring every 2w