Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Aug 1;163(8):bqac082.
doi: 10.1210/endocr/bqac082.

Maternal Thyroid Function and Birth Weight in Twins

Xiao Song Liu  1 , Xiu Juan Su  2 , Guo Hua Li  3 , Shi Jia Huang  1 , Yang Liu  1 , Han Xiang Sun  1 , Qiao Ling Du  1
Affiliations

Maternal Thyroid Function and Birth Weight in Twins

Xiao Song Liu et al. Endocrinology. .

Abstract

Context: Thyroid hormones are associated with birth weight in singleton pregnancy. Twin pregnancies need more thyroid hormones to maintain the normal growth and development of the fetuses compared with single pregnancy.

Objective: We aimed to investigate the association of thyroid hormones and birth weight in twins.

Methods: This was a retrospective cohort study in a Chinese population. Pregnant women who received regular antenatal health care and delivered live-born twins from 2014 to 2019 were included (n = 1626). Linear mixed model with restricted cubic splines and logistic regression models were used to estimate the association of thyroid hormones with birth weight and birth weight discordance in twins.

Results: We observed that both thyrotropin (TSH) and free thyroxine (FT4) were not associated with birth weight in twins overall, while when stratifying on fetal sex or chorionicity, there were nonlinear association between FT4 levels and birth weight in boys (Pnonlinear < .001) and in dichorionic (DC) twins (Pnonlinear = 0.03). Women with levels of FT4 lower than the 10th percentile had a higher risk of birth weight discordance in their offspring than women with normal FT4 levels (range, 2.5 to 97.5 percentiles) (odds ratio = 1.58; 95% CI, 1.05-2.33).

Conclusion: Our study suggests there was an association of FT4, but not TSH, with birth weight and birth weight discordance varied by sex and chorionicity. These findings could have implications for obstetricians to be aware of the importance of FT4 levels in preventing birth weight discordance in twin pregnancy.

Keywords: birth weight; birth weight discordance; thyroid function; twin pregnancy.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Association of thyrotropin (TSH) and free thyroxine (FT4) levels with birth weight. Linear mixed model with restricted cubic splines did not indicate a nonlinear association of birth weight with TSH level (P for nonlinear = .88 [left]) and FT4 levels (P for nonlinear = .06 [right]) after excluding the outliers (n = 8).
Figure 2.
Figure 2.
Association of thyrotropin (TSH) and free thyroxine (FT4) levels with birth weight stratified by fetal sex. We observed that there was a nonlinear association between FT4 levels and birth weight in boys (P < .001), but not in girls (P = .56), and there was no association of TSH levels with birth weight both in boys and girls (P > .05).
Figure 3.
Figure 3.
Association of thyrotropin (TSH) and free thyroxine (FT4) levels with birth weight stratified by chorionicity. We observed that there were no associations of TSH and FT4 levels with birth weight in monochorionic (MC) twins (P > .05), while there was a nonlinear association of FT4 levels with birth weight in dichorionic (DC) twins (P = 0.03).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Kampouri M, Margetaki K, Koutra K, et al. . Maternal mild thyroid dysfunction and offspring cognitive and motor development from infancy to childhood: the Rhea mother-child cohort study in Crete, Greece. J Epidemiol Community Health. 2021;75(1):29-35. doi:10.1136/jech-2019-213309 - DOI - PMC - PubMed
    1. Giannocco G, Kizys MML, Maciel RM, de Souza JS. Thyroid hormone, gene expression, and central nervous system: where we are. Semin Cell Dev Biol. 2021;114:47-56. doi:10.1016/j.semcdb.2020.09.007 - DOI - PubMed
    1. Schneuer FJ, Nassar N, Tasevski V, Morris JM, Roberts CL. Association and predictive accuracy of high TSH serum levels in first trimester and adverse pregnancy outcomes. J Clin Endocrinol Metab. 2012;97(9):3115-3122. doi:10.1210/jc.2012-1193 - DOI - PubMed
    1. Shinohara DR, Santos TDS, de Carvalho HC, et al. . Pregnancy complications associated with maternal hypothyroidism: a systematic review. Obstet Gynecol Surv. 2018;73(4):219-230. doi:10.1097/OGX.0000000000000547 - DOI - PubMed
    1. Idris I, Srinivasan R, Simm A, Page RC. Maternal hypothyroidism in early and late gestation: effects on neonatal and obstetric outcome. Clin Endocrinol (Oxf). 2005;63(5):560-565. doi:10.1111/j.1365-2265.2005.02382.x - DOI - PubMed

Publication types

Substances