It is common to observe large between-herd variation in transition management practices and reproductive performance of dairy cows under certified organic management. Metabolic and infectious diseases increase the risk of voluntary and involuntary culling within 60 d in milk (DIM) and are a major animal welfare issue for the dairy industry in both organic and conventional herds. Reproductive performance of lactating dairy cows directly influences the annual frequency of calving; thus, the number of replacement heifers and milk yield (due to extended low productivity and dry period). Recent studies involving 4,111 pre- and postpartum cows from organic herds showed that cows experiencing hypocalcemia (HYPO) at calving had greater proportion (P < 0.05) of metritis and culling rate within 60 DIM compared with non-HYPO cows. Furthermore, uterine diseases (primarily metritis and purulent vaginal discharge [PVD]) significantly increased (P < 0.05) the risk of cysts at 26 ± 3 DIM, reduced cyclicity (progesterone concentration ≥1 ng/mL) at 40 ± 3 DIM as well as the hazard of pregnancy up to 300 DIM, and increased the risk for pregnancy loss. Regardless of parity, uterine diseases (RP, metritis and PVD) had an additive effect on milk loss and quality for at least one of the first 4 DHIA test-days (P < 0.05), but was not different at later tests. Many factors such as feed management (i.e., diets, dry matter intake and water quality) and comfort (e.g., resting time) of transition cows determine the energy (e.g., BHBA, NEFA) and calcium balance. These factors also determine the status of the immune system of the animal; thus, the prevalence of infectious diseases in postpartum cows (e.g., metritis). Implementing a proactive transition cow program that focuses on preventing metabolic diseases by managing the leading risk factors (e.g., diets, resting time of cows per day, dry matter intake) will significantly reduce calving-related losses and improve uterine environment and ovarian structures (cyclicity); thus, improving the overall performance of lactating dairy cows and profitability of the herd, regardless of size.