Lactation duration and long-term thyroid function: A study among women with gestational diabetes

Pranati L. Panuganti, Stefanie N. Hinkle, Shristi Rawal, Louise G. Grunnet, Yuan Lin, Aiyi Liu, Anne C.B. Thuesen, Sylvia H. Ley, Sjurdur F. Olesen, Cuilin Zhang

Research output: Contribution to journalArticle

3 Scopus citations


Lactation is associated with reduced postpartum weight retention and a lower risk of several cardiometabolic disorders in population-based studies. We examined the association between lactation and long-term thyroid function among women with history of gestational diabetes mellitus (GDM), a high-risk population for subsequent metabolic complications. The study included 550 women who developed GDM in the Danish National Birth Cohort (1996–2002) and followed-up in the Diabetes & Women’s Health Study (2012–2014). We assessed adjusted associations between cumulative lactation duration and concentrations of thyroid stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) measured at follow-up. Women with longer cumulative lactation duration tended to have higher fT3 levels (adjusted β and 95% confidence interval (CI) for ≥12 months vs. none: 0.19 (0.03–0.36); p-trend = 0.05). When restricted to women with a single lifetime pregnancy to control for parity (n = 70), women who lactated for >6 months (vs. none) had higher fT3 levels (0.46 pmol/L (0.12–0.80); p-trend = 0.02) and a higher fT3:fT4 ratio (0.61 (0.17–1.05); p-trend = 0.007). Our findings suggested that a longer duration of lactation may be related to greater serum fT3 levels and fT3:fT4 ratio 9–16 years postpartum among Danish women with a history of GDM. The association was particularly pronounced among women who only had one lifetime pregnancy.

Original languageEnglish (US)
Article number938
Issue number7
StatePublished - Jul 21 2018



  • GDM
  • Lactation
  • Thyroid
  • Thyroid antibodies
  • Thyroxine
  • Triiodothyronine

ASJC Scopus subject areas

  • Food Science
  • Nutrition and Dietetics

Cite this

Panuganti, P. L., Hinkle, S. N., Rawal, S., Grunnet, L. G., Lin, Y., Liu, A., Thuesen, A. C. B., Ley, S. H., Olesen, S. F., & Zhang, C. (2018). Lactation duration and long-term thyroid function: A study among women with gestational diabetes. Nutrients, 10(7), [938].