What is twin birthweight discordance?

Area of Science:

• Obstetrics and Gynecology
• Neonatal Perinatal Medicine
• Reproductive Health

Background:

• Twin birthweight discordance is a common concern in multiple gestations.
• Understanding the threshold of discordance associated with adverse outcomes is crucial for clinical management.
• Previous studies have yielded mixed results regarding the impact of discordance on perinatal health.

Purpose of the Study:

• To determine the specific level of twin birthweight discordance across gestational ages associated with increased perinatal morbidity, neonatal death, or congenital anomalies.
• To evaluate the independent contribution of birthweight discordance to adverse perinatal outcomes.
• To inform antepartum management strategies for twin pregnancies.

Main Methods:

• Retrospective study of 194 sets of twins born between 1982 and 1985.
• Birthweight discordance calculated as (larger birthweight - smaller birthweight) / larger birthweight x 100.
• Analysis of perinatal morbidity, neonatal death, and congenital anomaly rates in relation to discordance levels and gestational age.

Main Results:

• Mean birthweight discordance was 10.3 +/- 8.5%, with variations across gestational age groups (e.g., 11.4 +/- 8.5% for 37-42 weeks).
• Perinatal morbidity, neonatal death, and anomalies were elevated with prematurity and when both twins were small for gestational age.
• No significant association was found between the level of birthweight discordance and increased morbidity, neonatal death, or anomalies.

Conclusions:

• Prematurity and both twins being small for gestational age represent greater risks to perinatal outcomes than birthweight discordance itself.
• Current findings suggest that antepartum management should prioritize addressing prematurity and growth restriction in twins.
• Birthweight discordance alone may not be a primary indicator for intensified antepartum surveillance or intervention.