10% of postpartum women are at risk of developing a depression and untreated postpartum depression has serious consequences.Thyroid dysfunction is associated with anxiety and depression.pregnancy is a time of significant changes in thyroid function.
Increased estrogen level lead to increased thyroid-binding globulin (TBG) levels .Increased renal clearance may decrease iodine levels.placenta produce several thyroid stimulating factors. Free T3 and free T4 usually remain within normal limits. Levels of TSH fall at the end of the first trimester and rise again to pre-pregnancy levels, and typically remain stable throughout the pregnancy.
Would TFT done at delivery tell us anything about PPD?
Sara M. Sylve n and colleagues investigated the association between TFT at delivery and risk for postpartum depressive symptoms at 5 days, 6 weeks and 6 months after delivery in a population based sample of 347 Swedish women.
1.6.4% of sample had TSH more than 4.0 mU/L . 3.6% had Thyroid antibody above normal levels.
2. There was a positive association between high TSH levels (defined as >4 mIU/L), with fT4 within the normal pre-pregnancy range at delivery and the development of self-reported depressive symptoms six months postpartum.It is unclear why this association does not become statistically significant until 6 months after delivery.
3.Negative association between free thyroxin levels and the risk for postpartum blues.
4. Lack of an association between TSH levels at delivery and depressive symptoms in the early postpartum period
Thyroid function was only assessed by a single blood sample at delivery.Changes in thyroid turnover is common during pregnancy.What is normal range in pregnancy is unclear (:Need for trimester or pregnancy specific values have been raised).
Conclusions: TFT may be used as a screening tool to identify individuals at risk of developing PPD and further psychiatric evaluation can be offered to those identified. However, further prospective study is required to confirm this findings and its usefulness.
Summary of the article:
Sylvén SM, Elenis E, Michelakos T, Larsson A, Olovsson M, Poromaa IS, Skalkidou A.Psychoneuroendocrinology. 2013 Jul;38(7):1007-13.