The nine months of pregnancy are divided into three trimesters. A single trimester comprises of three months.
3M(First Trimester) + 3M(second Trimester) + 3M(Third Trimester) = 9 Months
♦The I(first) trimester is the time when the basic structure of your baby is formed, II(second) trimester is the time when the structures matures & refines and becomes complete and in the III(third) trimester the baby grows, it gains length & weight and nutrition.
In the III trimester especially in the last month the placenta becomes freely permeable and allows all the nutrients to transfer freely from mother to baby, hence the last month too is very important to the health of baby.
- In the first 3 months your body makes adaptations to accept the growing fetus. This is hence the most crucial part of pregnancy.
- Ovum and Sperm Fertilize to form a zygote ( in the fallopian tube) which moves towards uterus, reaches uterine cavity and attaches itself to the inner lining of uterus ,this is called IMPLANTATION, and occurs by day 21 from LMP (Last menstrual period).
- From here the durable and multilayer relations between mother and fetus is set.
Why so many miscarriages occur in First trimester?
- The steps from fertilization to implantation are very important and since at this time the baby is just a very small bundle of cells, it is highly likely that some things do not go quite right and the conception does not occur!
- Also many a times the fertilized conceptus has chromosomal aberrations or other defects which lead to rejection and non implantation of fetus by the body itself.
- Added to these, this is the time when the internal organs of fetus are being formed and exposure to any stress, alcohol, tobacco, drugs, medicines,infections, radiation etc are absolutely damaging and have the maximum impact!
Hence first trimester is the time of maximum incidence of miscarriages
Points To Note-
- At 4 weeks from your LMP (On the first day after missing your periods) one can test pregnancy by a home pregnancy test kit.The test should be taken on morning’s first urine sample, which measures the beta HCG levels in urine. On the test kit two lines indicate a Positive test.
- Beta HCG level < 5mlu/ml = negative
5-25 = equivocal
>25 = positive
- Home pregnancy test should be repeated after 2-3 days to get a strongly positive test.
- Next important thing to keep in mind in the first trimester is the risk of ectopic pregnancy! It happens if the fertilized zygote does not travel all the way from fallopian tube to inside the uterine cavity and gets attached on the way. This is a life threatning situation for the mother and if found should be treated immediately.
Symptoms of Pregnancy in First Trimester:
- At 5weeks, symptoms of pregnancy start appearing like :
-Bigger & more sensitive breasts
-nagging pain in abdomen
-increased sensitivity to smells
– Drowsiness, fatigue etc.
- During the 5th week respiratory and nervous system along with blood vessels and heart begin to form.
- At 6 weeks fetus heart starts to beat. It is at this time that the first ultrasound is done and fetal heart beat is looked for! The first Ultrasound (Sonography) thus, is vital to confirm the presence of a live fetus in its appropriate place in uterus.
- The fetal cardiac activity can be seen at 6 weeks on trans vaginal ultrasound and at 8 weeks on trans abdominal ultrasound(because at 6 weeks uterus is not large enough to be accurately viewed per abdomen).
- At 6-8 weeks (in the 2nd month of pregnancy), one should get herself booked he in an antenatal clinic. On yours visit your doctor will take your weight, pelvic sizes, urine and blood samples, tests for HIV, hepatitis, thyroid etc. and check your Blood Pressure.
- Again you will be advised to take extreme care; avoid stress,exertion, infections, trauma, alcohol, drugs, tobacco self-medicines; have good rest, stay active and take a balanced diet.
- One should continue folic acid supplementation throughout the first trimester.
- By completion of 8 weeks the outer structure of baby is quite formed and it starts looking like human and is called a “fetus” now!
- By the 9th week brain continues to develop and baby’s limb movements become more co-ordinated. It is the size of a cherry now.
- At 12 weeks the foetus is completely formed externally and looks like a little man. Its internal organs have also been formed
This is the reason why at the completion of 12 weeks ( I Trimester), the second USG is done to look for any gross congenital anomaly. Also it is at this time that the size & condition of uterus, location of placenta, fetal size, single or multiple gestation, gestational sac etc. are looked and commented upon. Various fetal parameters are measured and approximate fetal age and EDD( Expected Date of Delivery) is given.
- By this time( completion of first trimester) a women should gain 2-3 kgs, but sometimes due to excessive nausea and vomiting there is no weight gain; which is covered up by the body later, in second trimester since nausea and vomiting wane by then.
- In the first trimester, there could be occasional bleeding /spotting at your scheduled due date, but one should be very cautious regarding unexplained vaginal bleeding because it could be caused by:
3)Local causes ( polyp, cervical cancer)
Hence any vaginal bleeding /spotting should be immediately reported to the doctor.
- Minor nausea & vomiting are a part and parcel of pregnancy and are a sign of hormonal changes made by body to accept pregnancy. Medications should be avoided to treat the same.
However “Hyperemesis Gravid arum” is a complication of pregnancy characterized by intractable nausea, vomiting and dehydration. It affects 0.5-2% of pregnant women and is usually encountered in 8-12weeks of pregnancy when Beta HCG levels are highest.For this iv(intravenous) hydration and medicines are needed and hence should be immediately reported to a doctor.
Care to taken in first Trimester-
- Applying Bio oils on the skin specially of tummy area ,back and buttocks should be started by 10-12 weeks to prevent stretch marks later on. The basic idea is to keep the skin well-oiled and to not let it dry ,to avoid stretch marks. Any oil like coconut oil or olive oil can also be used. It should be applied twice, once after bathing and second before going to bed.
- As repeatedly told that first trimester is the time of maximum care! It is the time when from a single cell to the complete fetus is formed! from free floatation in female vaginal tract to attachment to the inner uterine lining to formation of placenta for nutritional exchange between mother and child, all happen during these weeks hence it is imperative to maintain caution during this time!