One of the essential things that a pregnant woman should do is to devise a pregnancy diet plan that consists of all the nutrients her body and the little life growing inside her need. It doesn’t have to be a very detailed day-to-day guide. A general diet plan would suffice, outlining which food groups she should have in her diet, which ones to minimize, and which food items to completely avoid.
Ideally, a doctor or a dietitian should help her devise such a pregnancy diet plan. But in many cases, the doctor whom she sees 
on her regular prenatal checkups will just give a quick overview of what she should be, and should not be, eating. The doctor will likely emphasize the nutrients that are critical for a healthy pregnancy. Furthermore, the doctor will also tell her if she is gaining weight as she should, or if some diet modifications are needed so that she can gain or lose more weight, as the case may be.
A pregnant woman needs more calories to support the growing demands of her body. Typically, she now needs an additional 100 to 300 calories per day. If she was underweight before she became pregnant, or if she leads a physically active lifestyle, she could need a larger amount of additional calories. Ideally, this should allow her to gain about two to four pounds in the first three months of her pregnancy. In the latter two trimesters, she should gain something like one pound each week.
The weight gain should be gradual. Too much weight gain is not good, because this will make it difficult to deliver the baby, who will also likely be born overweight. The pregnant woman shouldn’t experience any weight loss, except for a small drop in weight that sometimes occurs in the last week or two of pregnancy, which is considered normal.
The most important nutrients that the pregnancy diet plan should provide are: calcium, iron, protein, vitamins A, B-1, B-12, C, and folate. These nutrients can be found in foods such as milk, cheese, sardines, yogurt, lean red meat, fish, poultry meat, liver, beans, peas, iron-fortified cereal, dark green vegetables, carrots, sweet potatoes, citrus fruits, bananas, whole grain cereals, nuts, prune juice and orange juice.
It doesn’t mean that a pregnant woman needs only those specific nutrients. Apart from them, she should also partake of balanced meals that supply all the nutritional demands of a normal person.
Prenatal supplements are also necessary, just to ensure that she gets all the vital nutrients, in the right amounts, in case her diet is deficient. A lot of people, including pregnant women, don’t have the luxury of carefully planning and preparing every meal; sometimes there isn’t even enough time to sit down to a proper meal. So, taking prenatal supplements is really a very useful safeguard.
Proper hydration is another essential component of a good pregnancy diet. Because a pregnant woman urinates a lot, she should replenish the amount lost by drinking plenty of fluids. Sufficient water intake also helps prevent constipation, another common problem in pregnancy. Eating lots of fiber is also very helpful in preventing or easing constipation.
Finally, to help decrease nausea and vomiting in pregnancy, it is better to eat about six smaller meals throughout the day rather than the traditional three square meals. This also ensures that her energy demands are met satisfactorily, and her blood sugar levels are kept stable. A pregnant woman is prone to hormonal mood swings; this could be made much worse if she experiences unstable highs and lows in her glucose levels.
The pregnancy diet plan should incorporate all these considerations. Similarly, there are specific nutritional requirements for a post-pregnancy diet and a breastfeeding diet that should be carefully considered to ensure the new mother’s continued health after she gives birth.