132
Views
3
CrossRef citations to date
0
Altmetric
Original Article

Prediction of birth weight discordance from fetal weight estimations at 21–24 weeks' scans in monochorionic and dichorionic twins

, , , , &
Pages 1944-1947 | Received 30 Jul 2016, Accepted 03 Sep 2016, Published online: 07 Feb 2017
 

Abstract

Objective: To evaluate if inter-twin estimated fetal weight (EFW) differences at 21–24 weeks’ scans predict birth weight discordance in monochorionic and dichorionic twins born at three gestational age periods.

Methods: We counted the number of pairs with discordant EFWs (EFWs greater than the mean + 1SD; i.e. a difference above 12% in dichorionic and 21% in monochorionic twins) derived during a 21–24 weeks’ scan as compared to actual discordant birth weight (>25%) in monochorionic and dichorionic pairs born at ≤32, 33–36 and >36 weeks.

Results: We studied 416 dichorionic and 244 monochorionic twins. The frequency of EFWs discordance at 21–24 weeks was the same for dichorionic and monochorionic twins but the total number of birth weight discordant pairs was significantly smaller among dichorionic twins (OR 0.2, 95% CI 0.1, 0.6). Generally, the positive predictive values for birth weight discordance by using the EFWs difference were quite poor, but always better in monochorionic than in dichorionic twins. Whereas the negative predictive value and hence the sensitivity for monochorionic twins was 100% irrespective of gestational age at birth, it was much lower in the dichorionic pairs.

Conclusion: Concordant EFWs at 21–24 weeks exclude discordant birth weight in monochorionic twins whereas discordant EFWs are poor predictors of birth weight discordance especially in dichorionic twins irrespective when the twins were born.

Declaration of Interest

The authors report no conflict of interest.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.