Hi punkgirl - you're asking about blood spots in the yolk of your egg - I used the BYC Search bar and found several threads about the topic, and here's some info for you. Basically, it's nothing to worry about - just remove the spots from the yolk with the tip of a fork before you cook the egg and you're good to go.
QUESTION:
What causes blood in eggs that are freshly laid?
ANSWER:
BLOOD SPOTS:
Blood spots occur when blood or a bit of tissue is released along with a yolk. Each developing yolk in a hen's ovary is enclosed in a sack containing blood vessels that supply yolk building substances. When the yolk is mature, it is normally released from the only area of the yolk sac, called the "stigma" or "suture line", that is free of blood vessels. Occasionally, the yolk sac ruptures at some other point, causing blood vessels to break and blood to appear on the yolk or in the white. As an egg ages, the blood spot becomes paler, so a bright blood spot is a sign that the egg is fresh.
Blood spots may appear in a pullet's first few eggs, but are more likely to occur as hens get older, indicating that it's time to cull. Blood spots may be triggered by too little vitamin A in a hen's diet, or they may be hereditary.
MEAT SPOTS
Meat spots appear as brown, reddish brown, tan, gray or white spots in an egg, usually on or near the yolk. Such a spot may have started out as a blood spot that changed color due to chemical reaction, or it may be a bit of reproductive tissue.
Perfectly safe to eat and you can bake with them just fine. People just overreact because all our store bought eggs are strongly candled and sorted to only sell the perfect ones as is. The rest are mixed into various other things they sell so you don't notice. It's also not all that uncommon. You'll see all sorts of odd things with eggs from your own flock. Most are just fine to eat even if they don't look like the pristine store bought eggs.