Transvaginal ultrasound-guided aspiration of unilateral twin gestation in the mare.
Authors: Govaere J L J, Hoogewijs M K, de Schauwer C, Dewulf J, de Kruif A
Journal: Equine veterinary journal
Summary
# Editorial Summary Twin pregnancies in mares pose a significant welfare and economic challenge, as dual-bearing pregnancies typically result in poor outcomes for both foals; whilst embryo reduction is highly successful before fixation (approximately day 16), pregnancies identified later require more sophisticated intervention techniques. This Belgian study evaluated transvaginal ultrasound-guided aspiration (TUGA)—a minimally invasive procedure using real-time ultrasound visualisation to aspirate one twin vesicle—across 35 clinical cases, analysing how mare age, parity and days in gestation influenced procedural success. Overall success rates were encouraging, though the authors identified that advancing gestational age presented the greatest technical challenge, with pregnancies beyond a certain timepoint demonstrating reduced likelihood of converting to viable singleton pregnancies. Multiparous mares and those of advanced reproductive age showed slightly improved outcomes compared to younger, primiparous animals, possibly reflecting uterine conformational changes that facilitate access. For practitioners managing twin pregnancies post-fixation, TUGA offers a viable middle-ground option between accepting the twin pregnancy or pursuing more invasive embryocidal techniques, provided the procedure is performed promptly once diagnosis is confirmed and with realistic client expectations regarding success rates at later gestational stages.
Read the full abstract on PubMed
Practical Takeaways
- •TUGA is a viable therapeutic option for twin reduction in mares when early embryo reduction methods have failed or are no longer applicable
- •Timing is critical—perform reduction before vesicle fixation when possible, as later procedures face greater technical challenges
- •Consider mare age and parity when counseling clients on likelihood of successful singleton pregnancy outcome
Key Findings
- •Transvaginal ultrasound-guided aspiration (TUGA) is effective for reducing unilateral twin vesicles to singleton pregnancies in mares
- •Success rate and difficulty of embryo reduction varies with gestational age, being more challenging after vesicle fixation
- •Age, parity, and days pregnant were analyzed as potential factors influencing TUGA outcome in 35 cases