Twin growth discrepancy in early pregnancy

Area of Science:

• Maternal-Fetal Medicine
• Reproductive Endocrinology
• Prenatal Diagnosis

Background:

• Early pregnancy ultrasound is crucial for monitoring twin gestations.
• Assessing fetal growth and development in early pregnancy is vital for identifying potential complications.
• Understanding predictors of single fetal demise in twin pregnancies can improve management.

Purpose of the Study:

• To determine if early fetal growth restriction in twin pregnancies, indicated by crown-rump length (CRL) discrepancy, predicts subsequent single fetal loss.
• To evaluate the predictive value of intertwin CRL discrepancy in the first trimester for spontaneous reduction to a singleton.

Main Methods:

• Retrospective analysis of prospectively collected data from 77 women with viable twin pregnancies.
• Transvaginal ultrasound at 7-10 weeks gestation to measure CRL and calculate intertwin discrepancy.
• Follow-up to compare CRL discrepancy in pregnancies with single fetal loss versus those with two viable fetuses at 11-14 weeks.

Main Results:

• A larger median CRL discrepancy was significantly associated with subsequent single fetal loss (42.0% vs. 6.1%, P < 0.0001).
• The likelihood of retaining both twins decreased significantly with increasing CRL discrepancy (97% for <20% vs. 0% for >60%).
• Receiver-operating characteristics analysis showed an optimal cut-off of 16.9% CRL discrepancy for predicting single fetal loss (AUC=0.93).

Conclusions:

• First-trimester intertwin crown-rump length discrepancy is a significant predictor of subsequent single intrauterine fetal loss.
• Early fetal growth restriction in one twin may precede spontaneous demise in the first trimester.
• This finding can aid in risk stratification and management of twin pregnancies.