When you are 4 weeks pregnant you are sure that you are pregnant. You have already peed on the stick and the pregnancy hormone has been revealed to you. Anyhow, you are still very active as you have not gained any weight. At this point, anyone who will know that you are pregnant will have been told by you as there is no way a layman will know that you are pregnant in one month.
Your baby is beginning to have form, although nothing much will happen this week. His little heart will start beating but it is going to be a few months before you can get that scan and listen to the fast movement of his heart in your womb. Your heartbeat will surprisingly increase a lot at this time. You can still maintain your very active lifestyle if you were very active. You can still run a mile if your body allows you but do not be disappointed if the next few months you will have to give up your training shoes for something flatter and more comfortable for your increasing weight. You may have to limit your exercises to just a walk in a day in the next few months. Anyhow, in the first month of pregnancy, implantation has already taken place and you will still have morning sickness accompanied by mood swings, which may or may not be severe. But each person is an individual so it may be very different for different women.
Morning sickness and mood swings are caused by the imbalance of hormones that are now taking their special place to support the pregnancy. They will also cause your breasts to become tender and you will feel as if you no longer fit into your regular bra. Your baby is about an inch in length and may not be scanned. Keep in mind that you will only be able to scan and see your baby when it is about three months in your womb. As has been said before, there is no part of the pregnancy that is as crucial as the first month. This is the time when you need to be taking your supplements and improving your quality of food. You may sabotage the health of your child for its lifetime if you smoke or drink heavily when you are in the first months of your pregnancy. Some developmental disorders are exacerbated by smoking and drinking so you need to drop the habit when you realize that you are pregnant. Avoid second-hand smoke as well, since it could also bring health problems to you and your baby.
Take your supplements and eat well; in quality and quantity. In essence, you need to look for the advice of a nutritionist when you want to know what to eat and in what quantity. This is highly depending on your activity levels and your daily needs now that you are eating for two. Take iron supplements and vitamin supplements if you are not able to provide all the needed nutrients in your meals-but let the nutritionist decide this for you.