What Is Considered the First Trimester?: The first trimester of pregnancy lasts roughly three months. During this time, the baby is the smallest and yet grows the most. The embryonic stage (when the baby is called an embryo) of pregnancy begins and runs from about the 5th to the 10th week of pregnancy.

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Are Headaches Normal in the First Trimester

Headaches are common in the first trimester of pregnancy, which are typically caused by increased hormones and increased blood volume. For some women who often experience migraine headaches, they may have fewer migraines once they become pregnant, while others may have the same or more migraines.
Pregnancy, Bleeding

Bleeding during all phases of pregnancy may be dangerous, even though it can be caused by a large variety of factors. You should call your health care professional if you have any signs of vaginal bleeding during your pregnancy.
Ectopic Pregnancy

Ectopic pregnancy is a condition in which a pregnancy develops inside of a Fallopian tube or outside of a woman's uterus. Causes and risk factors for ectopic pregnancy include previous Fallopian tube infections (pelvic inflammatory disease, Chlamydia, gonorrhea), previous surgery to the abdomen, use of fertility medications, prior tubal pregnancy, and use of an IUD. Symptoms of ectopic pregnancy include pelvic pain and vaginal bleeding. If you suspect you have an ectopic pregnancy, medical care should be sought urgently.
Home Pregnancy Test

Home pregnancy tests are kits that contain a test to determine if a female is pregnant. Home pregnancy tests are available over-the-counter (OTC) and do not need a prescription. There are a variety of home pregnancy tests available. The accuracy of home pregnancy tests depend upon how well instructions are followed, and how the test kit was used. A pregnancy test performed in a doctor's office is the most accurate test to determine if you are pregnant.
How Much Weight Do You Gain During Pregnancy

When a woman gains too much weight during pregnancy, it can increase the risk of complications such as gestational diabetes, preeclampsia, and cesarean delivery. Healthy weight gain during pregnancy, which depends on pre-pregnancy Body Mass Index (BMI), however, can reduce the risk.
How Much Weight Gain Is Normal in First Trimester

In the first trimester of pregnancy, a woman will not gain much weight because the baby is still very small at this stage. During this time, women are advised to gain between 1 to 4 pounds, which can sometimes be difficult if they experience morning sickness.
How Soon Will A Pregnancy Test Read Positive

Pregnancy tests may be taken after a woman’s menstrual period is late. Implantation bleeding happens at 6 to 12 days into the pregnancy when the fertilized egg attaches to the inner lining of the uterus, causing light vaginal bleeding. About four to five days after implantation bleeding, pregnancy hormones in the body reach detectable levels in the blood. For at-home urine pregnancy tests, it may take up to 7 days post-implantation to reach detectable levels for testing.
Pregnancy, Vomiting

Morning sickness, or vomiting during pregnancy, is very common during the first three months of pregnancy. "Morning sickness" does not mean that nausea and vomiting only occur in the morning; symptoms can occur at any time of day. Talk with your doctor if you have persistent vomiting and/or nausea during pregnancy.
PMS vs Pregnancy Symptoms and Signs

Premenstrual syndrome (PMS) is a variety of symptoms and signs that about 90% of women experience within the two weeks up to the start of her menstrual period. Pregnancy is the period in which a fetus develops in a woman's uterus, usually lasting about nine months (about 40 weeks). PMS and early pregnancy share symptoms and signs like mood changes, headaches, back pain, weight gain, breast pain or tenderness, and abdominal cramping. Some of the main differences between PMS and early pregnancy symptoms are the amount of vaginal bleeding, how long fatigue lasts, and the strength of the abdominal cramping. PMS symptoms that don't occur during pregnancy are joint pain and acne flare-ups. Moreover, PMS symptoms are fairly predictable. Early pregnancy symptoms and signs that do not occur with PMS are a vaginal discharge and darkening of the nipples. The only way to find out if you are pregnant is with a pregnancy test.
Pregnancy Week by Week

Pregnancy occurs when an egg is fertilized by a sperm, grows inside a woman's uterus (womb), and develops into a baby. In humans, this process takes about 280 days.
Pregnancy, Round Ligament Pain

Many pregnant women experience abdominal pain for a number of reasons. Often, round ligment stretching is to blame. The round ligament is a muscle that holds the uterus in place, and it stretches as the fetus grows, causing pain. Treatment includes acetaminophen (Tylenol) and activity modification. Though round ligament pain is a completely natural an benign condition of pregnancy, other types of abdominal pain can indicate serious problems; seek medical care if symptoms become serious, for instance, if you have a fever, chills, painful urination or difficulty walking.
Pregnancy Symptoms

The symptoms of early pregnancy a pregnant woman may experience include missed periods, abdominal bloating, nausea and vomiting, breast tenderness and pain, food cravings, fatigue, frequent urination, elevated body temperature, changes in nipple color, darkening of the skin (melasma), mood swings, stress, headaches, and other symptoms.
What Does the First Trimester Screening Test For

Between the 11th and 13th week of pregnancy, a woman will have an ultrasound and blood screening test to estimate the probability a genetic disorder and identify risks for specific chromosomal abnormalities, including Down Syndrome (trisomy-21), trisomy-18, and trisomy 13. The first trimester screening test is not a diagnostic test and does not provide a definitive diagnosis.
What Happens to the Baby in the First Trimester

The first trimester of pregnancy is the first three months of pregnancy, or up until about Week 12. The baby grows the most during the first trimester, which includes the formation and development of the body's major organs, the heartbeat being able to be heard on a Doppler, external genitalia formed, and more.
What Should I Avoid During My First Trimester

During the first trimester of pregnancy, there are many things you should avoid to stay healthy and protect your baby. Lifestyle habits to stop or avoid during pregnancy include smoking, drinking alcohol, gaining too much weight, consuming too much caffeine, eating certain foods like raw or undercooked meat and eggs, raw sprouts, some seafood, and others.
What Week Do Pregnancy Symptoms Start

Pregnancy usually takes about two to three weeks after sex to occur. Pregnancy begins when a fertilized egg attaches to the wall of the uterus, and symptoms may start in some people as early as a week after this occurs. Other people may have no signs other than a missed period until a few months into the pregnancy.
When to Take a Pregnancy Test If You Have PCOS

Polycystic ovary syndrome (PCOS) is a hormonal condition in women in which levels of androgens (male hormones) are elevated, resulting in irregular menstrual periods because monthly ovulation is not occurring. Women with PCOS are usually advised not to take pregnancy tests before a missed period and to avoid using “early result” pregnancy tests because false negatives are more likely to occur with those types of tests.

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Morning Sickness (Vomiting During Pregnancy) Morning sickness, or vomiting during pregnancy, is very common during the first three months of pregnancy. "Morning sickness" does not mean that nausea and vomiting only occur in the morning; symptoms can occur at any time of day. Talk with your doctor if you have persistent vomiting and/or nausea during pregnancy.