In this Spanish study, 119 women were prospectively included: 32 egg donors donors, 31 patients with Unexplained Infertility (UI), 26 with IF (Implantation Failure) and 30 with RSA (Recurrent Spontaneous Abortion—i.e., recurrent miscarriages). The prevalence of thyroid autoimmunity in women with IF (anti-TPO antibodies, P = 0.009) and UI (anti-TPO, P = 0.002) was significantly increased in comparison to those with RSA. There was also a trend towards a higher prevalence of thyroid autoimmunity in the UI and IF groups than in the control group. TSH and free thyroxine levels all remained within a normal range.
The authors conclude "thyroid autoimmunity is strongly related to UI and IF (Infertility)."
The good news is that this is incredibly easy to address using thyroid hormone in any women whose "Anti-TPO Antibody" blood test is elevated. As a fringe benefit, giving thyroid to pregnant women with this blood test abnormality (which is common) decreases miscarriage rates from over 13% to less than 2%.
If this therapy and testing were expensive instead of dirt cheap, every doctor would know about it. No one pays for us to learn about the cheap stuff.
BOTTOM LINE: Any one with unexplained infertility or miscarriages deserves a trial of thyroid hormone (60 mg Armour Thyroid, or 100 mcg Synthroid if your doctor has been brainwashed to avoid natural thyroid). Also, all pregnant women should have an Anti-TPO antibody blood test and receive thyroid hormone if it is elevated. Period! (see my article discussing thyroid tests and pregnancy).
"The role of thrombophilia and thyroid autoimmunity in unexplained infertility, implantation failure and recurrent spontaneous abortion," Hum Reprod. 2008; 23(2):278-84 (ISSN: 1460-2350) Bellver J; Soares SR; Alvarez C; Muñoz E; Ramírez A; Rubio C; Serra V; Remohí J; Pellicer A
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