A full guide on the Stages of Pregnancy

A full guide on the Stages of Pregnancy

Pregnancy, also called gestation, is a period after the fertilization of the egg when the fetus grows in the mother's womb till the baby is delivered. It usually lasts about 9 months or 40 weeks from the last day of your menstrual flow. 

This guide will help you understand everything you need to know about the stages of pregnancy. 

Stages of Pregnancy

The stages of pregnancy is divided into three called trimesters. As such, the first trimester lasts from week one to week twelve, the second trimester from week thirteen to week twenty-six, lastly the third trimester lasts from week twenty-seven to the end of pregnancy birth.

Each part of the trimester is marked by its peculiarities, as you will soon discover for both mother and baby. 

When does pregnancy start?

When does pregnancy start?

Before we go further, we want to address a question that has stirred a lot of debate in recent times especially between the pro-life and pro-choicers side of the pregnancy termination. 

When does pregnancy start? The truth is, there are a lot of variables that make answering this question tricky at best. For you to land a verdict that is somewhat accurate or satisfactory you will need to consider the events that gave rise to pregnancy in the first place conception and implantation.


After intercourse, 300 million sperm are released in the medium called semen. This is the story of an epic battle for one of the sperms to fertilize the egg in the face of incredible odds. For this fertilization to turn a success, the egg has to be first released in the process called "ovulation" aided by the interplay of the female hormones.

This number is cut short when a good number of sperm are flowing out of the vagina and some other millions die due to the acidity of the vagina.

Notwithstanding, a lot still survive, courtesy of the alkalinity of the semen. Those who survive swim towards the cervix. The cervix is a cylindrical tissue lower part of the tissue that connects the uterus to the vagina. The cervix is normally tightly closed to keep the pregnancy in place and only dilates when it is time to deliver. It also slightly opens when the woman ovulates letting her drain menstrual flow.

The sperms pass through the lumen of the cervix to get to their distinction to the egg in the fallopian tubes. Some millions are caught up in the cervical mucus and subsequently die off, others fall behind and in time will be the backup, while some keep the foot on the gas to get the destination.

The remainder swims towards the tubes, one-half swim towards the tube containing unfertilized egg while the other half swim towards the other tube containing fertilized egg. 

In the fallopian tubes, the motion of sperm is facilitated by the female genital tract that also releases certain chemical factors that cause changes in the sperm and makes them swim faster. 

The sperms reach their destination, the egg. The sperm later fuses with the egg in a process called conception or fertilization. This is when the life of a little one has started. It should also be remembered that it is now that the sex of the baby is determined.


Implantation is the aftermath of the events of fertilization. The fertilized egg stays in the fallopian tube and starts active exponential division. After 6-7 days after fertilization, the zygote, now embryo, moves to and implants on the lining of the uterus. The motion of the fertilized egg is aided by the motion of the cilia that directs it to the uterus. In a related development, the uterus gets thicker and the cervix is sealed off by a mucus plug.

This implantation is accompanied by spotty bleeding called implantation bleeding after 1 or 2 days  And sometimes cramps that most women mistake for the usual menstrual cramps. 

There is a lot that can happen between point A fertilization and point B implantation. The egg can be implanted in the wrong site ectopic pregnancy and cause serious complications in the mother if not medically addressed in the proper manner and time. As a rule of the thumb, any pregnancy that implants in the wrong site must be removed surgically. Hence, an egg may be fertilized by not implanting properly, and this sums up the argument. Fertilization is as important as implantation.

When to contact a healthcare provider about a new pregnancy?

When to contact a healthcare provider about a new pregnancy?

The best time to contact your doctor is when you start to notice the symptoms of pregnancy. The initial symptoms of pregnancy are not specific and can differ between mothers. Nevertheless, the most common ones include:

Spotty bleeds and mild cramps 

A good number of women experience spotty bleeding on the first day after implantation. This can be followed by mild cramps in the first few weeks post conception.

Missed menstrual flow: Most people believe that this is the telltale sign of pregnancy, it is entirely not true as other disease entities can manifest such symptoms. Nevertheless, if you miss your period, report to your doctor who should recommend relevant pregnancy tests.

Changes in the breast and Nipple 

The interplay and increases in hormones cause the breast to become fuller, heavier, and sometimes painful to touch. This is paralleled by the darkening of the areola 


This feeling is commonplace with pregnant women. Funnily enough, unsuspectingly pregnant are alarmed at this point and may seek advice that may be futile at this stage of unknowns. 

The hormones are also at play here as always. They lower blood sugar in pregnancy. And no blood sugar means no energy! Hence it is expected you may want to eat more than you used to. 

Morning Sickness

This is the most known pregnancy symptoms, it is marked by nausea and incessant vomiting especially in the early hours of the morning, hence the name.

There is a related aversion to foodstuff that pregnant people used to eat before pregnancy. There is also what is known as pica, an unusual craving for non-nutritive substances such as paper, dirt, chalk, etc.

Frequent Urination

 Around the sixth week of pregnancy, you may notice that you may start to urine more frequently. Just relax! It is probably the pregnancy.


The hormonal changes could also stifle bowel movements making it harder to poop at times. Try eating food that is rich in fiber and drinking enough water.

Other common symptoms include headaches and back pain. If you notice any of these Symptoms listed above, especially missed periods and morning sickness, consult your doctor. He should run relevant tests, if he confirms the pregnancy, then booking starts. Booking is a 4 or 5-weekly appointment with the doctor and midwives to monitor the progress of your pregnancy and administer necessary medications. As such making sure that you deliver safely at long last.

Stages of Pregnancy by Trimester

Stages of Pregnancy by Trimester

The period of pregnancy is largely divided into three sections each is approximately 13 weeks and is marked for important events that form and shape the baby's development. As for changes, the mother is not left out as diverse modifications are made to help her cope with the pregnancy and for what to come when she finally puts to bed. Keep in mind, that weeks are usually counted from the last date of your menstrual flow. The stages are:

First trimester

The first trimester Usually starts from week one of pregnancy and ends at week 12. 

Changes in the mother

Most mothers notice they are pregnant 4-6 weeks after fertilization. Common signs include:

  • Morning sickness
  • Increased heart rate
  • Tiredness
  • Headaches
  • Constipation

Changes in the baby

The fertilized eggs start to actively divide into a mass of cells. Soon after, it implants to the walls of the uterus when it continues its division. 

This is a time of rapid growth, as such you must avoid drinking alcoholics or smoking as that may, hopefully not, mess with the baby's development and culminate in serious complications in the baby. Try as much as possible to maintain a healthy diet. Your baby needs it!

In the first trimester, the primordial forms the foundations of all the organs are formed. As early as week six, these changes happen:

  • The baby's heart starts beating for the first time
  • The baby's face starts to look more human
  • The ears migrate from the front of the heads to the side of the head
  • The external genitalia develops to a degree making it possible to know the sex of the baby via ultrasound
  • The guts loop formation kickstarts

Second trimester

This period starts from week 13 to week 27. 

Changes in the mother

Most mothers describe it as the most comfortable trimester of the three. Reason being that most symptoms of pregnancy start disappearing at this stage, plus there is a boost in your energy levels. 

This is when you start putting on a few pounds, and finally, the baby bump appears. 

However, symptoms like heartburn increased appetite, and leg cramps started. There are also varicose veins, backaches, nasal congestion. These symptoms are caused by the pressure the growing fetus applies on different organs in the body.

Changes in the baby

One of the most beautiful things in the second trimester is when the mother can feel the baby kicking. This beautiful event starts around the fifth month. In addition, the baby lengthens and gains more weight. Organs like the heart, the brain, kidney, the lungs continue their development.

Third trimester

The third trimester usually from week 28 till birth. 

Changes in the mother

The D-day is finally approaching, hence the need to see the doctors more often. The doctors run series of tests to determine your urine protein levels to rule out kidney pathology, blood pressure to rule out hypertension.

They also check the competency of your cervix, the baby's position, etc. You must restrict traveling to the minimum. This helps the pregnancy.

Changes in the baby

Some changes in the baby at this stage include:

  • The baby adds more weight and lengthens
  • The baby is covered with a white substance called vernix caseosa
  • At seven months the baby attains a state of viability. That means the baby can survive if delivered

Stages of pregnancy FAQs

Can I Drink While Am Pregnant?

The FDA has not established a safe level of alcohol in pregnancy. This means that it is in you and your baby's best interests that you avoid alcohol completely.

Alcohol has been linked with fetal alcohol syndrome. Fetal alcohol syndrome is a spectrum of disorders caused by exposing the fetus to alcohol. The symptoms include poor coordination, low weight, hyperactivity, growth deficiency, learning disabilities, atypical face, mental retardation, difficulty in school, etc. 

What Activities Should I Avoid While I'm Pregnant?

Activities like skydiving, skiing should be avoided. At the third traveling should be restricted. However, most other exercises like jogging, swimming are allowed.

Is Intercourse Safe During Pregnancy?

Yes, it is. Sex has not to be linked with miscarriage. The only time to avoid is in cases of complications in the pregnancy like threatened abortion, premature rupture of membrane, preeclampsia, etc.

I Feel So Tired. Is It Normal?

Feeling tired is commonplace in pregnancy. There is a lot of shift in the hormones plus the demands of the growing baby results in low blood sugar.


Ears form, eyes form, mouth forms, nose, hands, everything. Pregnancy is an event-filled period in the life of A mother. This period is divided into trimesters, each of which bears its peculiarities.

Most pregnancies first manifest with the mom starting to feel weird with persistent vomiting, nausea, and missing periods. You should check in with your doctor at this point. 

If—hopefully!—the pregnancy is confirmed, then your booking starts. This strong of appointments make certain everything checks out.