The first trimester of pregnancy is the most difficult part in my opinion and one can expect a barrage of symptoms, physical and emotional changes. This is when the various pregnancy hormone levels start rising and they are partly responsible for the symptoms you may experience. However these changes vary from one person to the other and even from one pregnancy to the next. Some of what to watch out for include:
Nausea and Vomiting
This is often referred to as "morning sickness" but this is a kind of misnomer as it isn't always limited to the morning. It may be provoked by sights and smells of food and a wide variety of other stimuli, including after finishing a meal. Some women may have a severe form known as hyperemesis gravidarum (simply means excessive vomiting of pregnancy) and thus require medical treatment. Majority of cases of morning sickness however can be managed by eating small frequent light meals and regular fluid intake.
Abdominal pain/Discomfort
One may also have a non-specific abdominal pain that is difficult to characterize, or more commonly bloating and discomfort. It typically comes up after eating but you may feel bloated all day long. Note that if you are having a specific cramping pain that is moderate to severe, or it is accompanied by vaginal bleeding, this may indicate something more problematic and you need to seek medical help immediately.
Fatigue
You may find yourself being unusually tired after little or no exertion. One reason for this is dilutional anemia, a situation in which your blood volume increases relative to the amount of red cells. There is also the tendency to sleep more often. If you were someone who previously had difficulty sleeping during the daytime, you can sure expect this to come easily to you during early pregnancy. The hormone progesterone has been implicated as a cause of this increased sleepiness.
Heartburn and Constipation
These are also due to rising levels of progesterone. Progesterone causes the muscles of the esophagus and bowels to be more relaxed and hence they tend to be more sluggish in emptying their contents leading to aforementioned problems.
Physical Changes
Breast tenderness and fullness is also a symptom of early pregnancy. However this shouldn't be too much of a problem as long as one wears comfortable bras. It is similar to breast changes one experiences during cyclical menses. You may also notice darkening of the area around your nipple. This will continue throughout pregnancy. Also, your lower abdomen starts rounding up as your uterus progressively enlarges to accommodate the growing fetus. At this stage though, most people can't tell from just looking that you are pregnant.
Food Cravings
These are almost classic and I have yet to meet anyone who didn't have one form or another of food cravings, from desiring foods that you were once very averse to, to always wanting to eat only your favorite food. Some women may crave non food substances such as clay; this is known as pica and could be an indication of an underlying iron deficiency. If this occurs, you need to mention it to your health care provider so appropriate tests can be carried out. There is also the reverse scenario in which you can't stand foods you previously adored and every time you see or so much as smell these foods, it brings a wave of nausea and or vomiting.
Emotional Changes
The first trimester is a time of some emotional upheaval. You are likely going to be more prone to mood swings, easy tearing, and increased anxiety. A wide variety of emotional distress is possible. Some women have reported feeling mildly depressed.
Finally, you can expect to have some, all or none of the above mentioned symptoms. If you do have the annoying symptoms, expect them to get better as you ease your way into the second trimester but don't expect a hard and fast cut off at three months. You may not get entire relief until the 5th month, and one or two may persist until you deliver for example heartburn.
So all said and done, is the first trimester all pains and no gains? In a way but of course the ultimate gain is your wonderful little baby developing in you. Legend also has it that women who experience this period in this trying fashion are more likely to have a natural, uncomplicated delivery!