What to Expect During Your 1st Trimester

Week by Week Timeline >> What to Expect During Your 1st Trimester

First Trimester Symptoms & the Embryonic Phase

In Part 4 we reviewed early fetal development in the weeks following implantation, as well as basic early pregnancy symptoms. As noted, the first signs of pregnancy, besides confirmation from a pregnancy test, include implantation bleeding, a missed period, morning sickness, fatigue, tender breasts and nipples, increased frequency of urination, and curious food cravings and hunger pangs.

Now we are at around 3 to 4 weeks since you ovulated and conceived. The embryo is now developing quickly and already the fundaments of organ, tissue, spine, and nervous system development are well underway. This stage of pregnancy is called the embryonic phase and lasts through your 8th week. .During this important stage, most of the critical organs have "sprouted", as have tiny, incipient arms. The neural tube (which will become the spine and nervous system) is also developing, as are the basic structures for blood circulation. In fact, the circulatory system begins to form in concert with, and underlying, the neural tube. During the 4th week of pregnancy, the fetal heart begins to beat, moving blood from the yolk sack into the placenta. Within the central part of the neural tube, we now see the early formation of the spinal cord and the brain.

Already, the sensory organs and tissues are on the move. As the brain develops, "sensory placodes" form in close proximity, including lens structures that will eventually develop into the eyes, and nasal and tiny aural features that will evolve into the nose and ears. Around the 4th week, we also see the appearance of "pharyngeal arches", which resemble the gills of a fish but have an entirely different function, ultimately exfoliating into several different physiological structures, including the jaw, mouth, teeth, tongue, neck, voicebox, throat, and several key glandular features.

First Trimester Pregnancy Signs and Symptoms: With all this activity going on, you must be feeling something! Besides the early signs indicated above, you should have a great deal of the hCG hormone rushing through your system. This will result in a positive pregnancy test - and you should see a very bold test line. The amount of hCG in your system can be an indicator of early pregnancy health and fetal development. Low amounts of hCG may even be an indication of pregnancy complications, including ectopic pregnancy. That said, a urine pregnancy test cannot yield quantitative hCG data; only a doctor can determine and interpret the results of a quantitative hCG pregnancy blood test.

During the embryonic phase, you may naturally find yourself on the hungry side. However, you also experience certain negative responses to specific foods that have nothing to do with morning sickness. Strong food and odor aversions may occur, and if you find the idea of eating a type of food disgusting, then simply avoid that food. Other strong food cravings may compensate.

Speaking of morning sickness, this pregnancy sign may increase as hCG and progesterone continue to course strongly through your system. A proven remedy like Preggie Pops or Preggie Pop Drops are effective in mitigating nausea. Typically, morning sickness will decrease as you near the end of your first trimester. Despite any ill-feelings or stomach discomfort, one obvious aspect of pregnancy is weight gain. During the first trimester, you can expect to gain anywhere from six to eleven pounds. Your doctor will be able to help you with nutritional questions and key pregnancy benchmarks that indicate good health.

Finally, during the first trimester, miscarriage (spontaneous termination of pregnancy within the first 20 weeks) is possible. Though many women are not aware of the fact, miscarriage is relatively common, and as many as twenty percent of pregnancies may end in miscarriage. Some pregnancies end even before you experience your first pregnancy symptoms. This can result in a phenomenon known as a "chemical pregnancy" in which enough hCG is produced to register a positive pregnancy test, but following tests indicate negative results (as hCG production stops following a very early miscarriage).

Often a miscarriage occurs because of abnormalities or early pregnancy complications. It is believed that about half of miscarriages occur to due chromosomal abnormalities. Signs and symptoms of miscarriage include abdominal cramping or pains, aches in the lower back area, and vaginal bleeding. However, vaginal bleeding by itself during pregnancy does not necessarily mean that you have had a miscarriage. In fact, in cases of bleeding during pregnancy, only 50% of cases will result in miscarriage. If you do experience bleeding, contact your doctor. While a miscarriage can be traumatic and very sad, it is a common experience so you are certainly not alone. Your doctor can answer any questions regarding miscarriage.

During this phase of critical embryonic development, a sound pregnancy diet and good health are cornerstones of pregnancy health. Eat right, eat healthy, and eat natural, preferably organic foods. Also, avoid certain types of seafood that may contain high amounts of mercury. Also avoid raw or undercooked meat or fish. Yes, sushi and sashimi are off the menu for a while... Organic or free-range meets are ideal, as they do not contain hormones or feed additives. Again, folic-acid containing leafy greens or prenatal vitamins are a essential during early pregnancy, particularly for neural tube formation. A high-quality prenatal vitamin with ideal dosing of folic acid, like Pregnancy Plus, is a must as well.

Go Back To...

> TTC Weeks 1 and 2: From Menstruation to Ovulation
> TTC Week 3: From Ovulation to Conception
> TTC Week 4: Implantation and the Luteal Phase
> Pregnancy Week 1: Early Pregnancy Symptoms & Fetal Development
> Pregnancy Calendar Home