In this study, we found that FT4 was significantly lower and CRP was significantly higher in the group with hypothyroidism in pregnancy combined with SIBO compared to the group without SIBO, suggesting that the mechanisms associated between hypothyroidism in early pregnancy and SIBO may involve alterations in small intestinal bacteria, inflammatory factors, etc. On the one hand, hypothyroidism‐induced alterations in intestinal function relocate intestinal bacteria in the small intestine (Kun et al., 2023). The gene discussed is CRP; the disease is hypothyroidism.