Table 3.
Thyroid-related fertility studies.
| Authors (reference) | Type of study | Study design | Aim | Results | Conclusion |
|---|---|---|---|---|---|
| Vaquero et al. (126) |
in vivo human female |
Clinical trial | Evaluation of the role of benign thyroid abnormalities in recurrent spontaneous abortion and evaluation of the effects of two different therapeutic protocols | Treatment of mild thyroid disorders with immunoglobulins resulted in termination of pregnancy in 54.5% of cases, while the use of replacement therapy in 81.2% of cases | Thyroid replacement therapy is more effective in the obstetric context than intravenous immunoglobulin |
| Kakita-Kobayashi et al. (127) |
in vitro human female |
Clinical experiment | Evaluation of the effect of thyroid hormone on decidualization in human endometrial stromal cells (hescs) and determination of its physiological roles in vitro through gene targeting | A significant increase in decidual response was observed after combined treatment with ovarian steroid hormones and thyroid hormone | Deciduality impairment is a possible cause of infertility in patients with subclinical hypothyroidism (SCH) |
| Barber et al. (128) |
in vitro human female |
Clinical experiment | Determination of the expression of thyroid hormone receptors in the extranodal trophoblast, elucidation of the effect of T3 on both the proliferation and differentiation of human trophoblast cells of various origins, and the determination of a potential interaction between EGF and T3 | T3 and EGF have an anti-proliferative effect on cells of the extranodal-like lineage (SGHPL-4), with a concomitant proliferation-promoting effect on JEG-3 choriocarcinoma cells | EGF and T3 have a synergistic effect in regulating human trophoblast proliferation and differentiation. |
| Giuliani et al. (129) |
in vitro animal (rat) female |
Clinical experiment | Evaluation of the effect of quercetin on the expression of genes encoding thyroid hormones and radioiodine uptake | Quercetin reduces the expression of the thyrotropin receptor, thyroid peroxidase and thyroglobulin genes, and also reduces the uptake of radioiodine by thyroid cells | Quercetin may act as a thyroid disruptor, supplementation should be used with caution |
| Condorelli et al. (130) |
in vitro human male |
Clinical experiment | Assessment the in vitro effects of levothyroxine (LT4) on conventional and biofunctional sperm parameters and its implications on fertility | Thyroid hormones have a beneficial effect on sperm mitochondrial function, oxidative stress and DNA integrity | Restoring the normal secretion of thyroid hormones is important in idiopathic male infertility |