When is assessment of chronicity most accurate?
Most accurate when ultrasound is performed in the first trimester or early second trimester
Ideally Between 11w0d and 13w6d
What maternal complications are common in women with multifetal gestation? List 4!
Hyperemesis, GDM, hypertensive disorders of pregnancy, anemia, PPH, c-section and postpartum depression
What are the known benefits of pregnancy reduction from triplets to twins as compared to those who continued with triplets?
List 3 benefits!
Lower frequencies of pregnancy loss, preterm birth, low birth weight infants, c-section and neonatal deaths with similar to those observed with women with spontaneously conceived twins.
**may decrease the risk of PEC**
What interventions have been shown to help prevent spontaneous preterm birth in women with multifetal gestations who are asymptomatic?
Trick question! NONE
TVUS cervical length, FFN, and home uterine monitoring have not been shown to help prevent PTB
What is the rate of twin-twin transfusion syndrome in mono-di pregnancies?
10-15%
What is the ultrasound sign you see with a di-chorionic twin gestation?
Lambda (aka delta or twin peak) sign: Indicates dichorionic twins with thickening at membrane insertion site
What medication aside from PNV and folate is recommended for all women with multifetal gestation and why?
Aspirin due to increased risk of PEC
What is the recommendation regarding fetal reduction in monochorionic gestations?
Recommended both fetuses of a monochorionic pair be reduced because if only one is reduced the negative effects on the development of the other fetus are unknown
What risks are associated with administering prophylactic tocolytics in women with multifetal gestations?
Greater risk of pulmonary edema
When does TTTS usually present?
Second trimester
What is the ultrasound sign you see with a monochorionic twin gestation?
T sign: Indicates monochorionic twins, with thin membrane and absence of thickening at membrane insertion site
What two complications are more common in twins born prematurely (<32 weeks) as compared to singleton pregnancies?
Twice the risk of high grade IVH and periventricular leukomalacia when compared with singletons of same gest age
(Will also accept CP as one of the answers as these likely contribute to increase prevalence of CP in multifetal gestations)
What is a feared complication of fetal reduction and how often does it occur?
Unintended loss of the pregnancy and occurs 11.1% in higher order multi-fetal gestation and 2.4% in twin gestation
When should you use tocolytics in multifetal gestation?
Clinically warranted to give brief course of tocolysis for up to 48 hours in setting of acute PTL in order to allow corticosteroids to be administered
How do you define fetal discordance and how do you calculate it?
20% difference in EFW between the larger and smaller fetus
Calculate Difference in EFW between the two fetuses/weight of larger fetus
1. How do you date spontaneously conceived twins?
2. If a woman presents beyond 14 weeks gestational age how do you date them?
1. By CRL of larger twin
2. Use head circumference of the larger twin
What is the risk of still birth and neonatal death for multifetal gestation vs singleton gestations?
5-fold increased risk of still birth and 7-fold increase risk of neonatal death primarily due to prematurity
What percentage of pregnancies conceived with ART are twins vs higher order multifetal gestations?
Data from 2017
25.5% are twins
0.9% higher order
Recently there has been a decrease in higher order multifetal birth rate
All relates to different variations in embryo-transfer practices among fertility clinics
When should you give a rescue course of betamethasone and how long after a prior course can you give a rescue course?
A single repeat course of antenatal steroids should be considered for women less than 34 weeks gestation who have imminent risk of preterm delivery within the next 7 days and whose prior course of steroid was given more than 14 days prior, however they CAN be administered as early as 7 days from prior dose if indicated clinically.
At what gestational age does growth slow in uncomplicated twin pregnancies?
Fetal growth in uncomplicated twin pregnancies occurs at similar rate as singletons until approx. 28-32 weeks at which time is slows
At what point does cleavage occur in di/di twins, mono-di twins, mono-mono twins, and conjoined twins?
Di di- Cleaves days 1-3
Mono-di- Cleaves days 4-8
Mono-mono- Cleaves days 8-13
Conjoined twins: days 13-15
What is the risk of preterm birth and specifically risk of birth before 32 weeks as compared to singleton gestations?
Six times more likely to give birth preterm and 13 times more likely to give birth before 32 weeks compared to singleton pregnancies
What are the difficulties with performing cell free DNA screening in twin pregnancies? List 2!
What should be first line treatment for tocolysis when used for short-term pregnancy prolongation?
Calcium channel blockers (nifedipine) or NSAIDS (indomethacin, kertorolac)
What is the name of the staging system for TTTS? What are the stages (can be brief description)?
The Quintero staging system
Stage I- oligo and Poly
Stage II – Bladder of donor twin not visible
Stage III- Doppler abnormalities (absent/reversed end diastolic flow in UA, absent/reversed a wave in DV, UV pulsations)
Stage IV- Hydrops in 1 or both twins
Stage V- Demise of one or both twins