Zinc is a very important element in the reproductive cycle of species. In humans, it is necessary for the formation and maturation of spermatozoa, for ovulation, and for fertilization. During pregnancy, zinc deficiency causes a number of anomalies: spontaneous abortion, pregnancy-related toxemia, extended pregnancy or prematurity, malformations, and retarded growth. Delivery is adversely affected by deficiency. These different effects of zinc can be explained by its multiple action on the metabolism of androgen hormones, estrogen and progesterone, together with the prostaglandins. Nuclear receptors for steroids are all zinc finger proteins. Zinc supplementation has already proven beneficial in male sterility and in reducing complications during pregnancy. However, it would be worth conducting larger-scale trials to confirm these beneficial effects.