Introduction to Pregnancy Symptoms
A missed menstrual period is often the first recognizable sign of a possible pregnancy, but there are other signs and symptoms of early pregnancy as well. Not all women have all symptoms or experience them in the same way. The most common first trimester symptoms are discussed in the following slides.
The first sign many women recognize as an early sign of pregnancy is a missed menstrual period (amenorrhea). Some women may experience lighter-than-normal periods, and they may also have spotting that can occur 1 to 2 weeks following conception.
A missed menstrual period can be caused by other conditions aside from pregnancy, so it is not always a definitive sign.
Breast Swelling, Tenderness, and Pain
Breast enlargement, tenderness, or pain similar to premenstrual symptoms, can occur early on during pregnancy. The breasts may feel full or heavy, and the area around the nipple (areola) may darken. A dark line called the linea nigra that runs from the middle of the abdomen to the pubic area may appear.
Nausea and Vomiting
"Morning sickness," or nausea and vomiting that usually occurs in the morning in early pregnancy usually happens between weeks two and eight of pregnancy. It's a misnomer because the nausea and vomiting can actually happen at any time. It's thought changes in levels of estrogen may play a role in developing nausea.
Another early pregnancy sign may be food cravings or aversions. Women may have an unusual urge to eat a particular food, even one she previously did not like, or she may be completely repulsed by a food she used to love. This is common and usually the food aversions fade with the first trimester.
Fatigue and Tiredness
The extra progesterone in a woman's body during pregnancy may cause her to feel fatigued and tired, and the need for naps increases. By the second trimester, energy levels usually rise again.
The rise in progesterone during pregnancy can also cause abdominal bloating, fullness, and gas. The weight gain in the first trimester is usually minimal, but cramping and bloating may make you feel as if you have gained more than the typical one pound per month.
The urge to urinate more frequently starts about six weeks into pregnancy, thanks to the hormone human chorionic gonadotrophin (hCG), which causes increased blood flow to the pelvic area and can stimulate the urge to urinate. Later in pregnancy, the urge to urinate may be increased by the growing baby in the enlarging uterus putting pressure on the bladder.
Elevated Basal Body Temperature
Many women hoping to become pregnant will chart their basal body temperature (the lowest body temperature in a 24-hour period, usually first thing in the morning after waking). The basal body temperature usually rises around ovulation and lasts until the next menstrual period. If the basal body temperature stays high for longer than that, it may indicate pregnancy.
Melasma (Darkening of the Skin)
During the first trimester, the skin on the forehead, bridge of the nose, upper lip, or cheekbones may darken. This is often referred to as the "mask of pregnancy," and the medical term is melasma or chloasma. It is more common in darker skinned women and those with a family history of melasma.
Mood Swings and Stress
Rapid changes in hormone levels during pregnancy may be responsible for mood swings and feelings of stress. Women may feel very emotional, anxious, or depressed, and have crying spells. Mood swings may be worst in the first trimester, easing up somewhat in the second, and coming back as the pregnancy nears the end.