Most of the pregnancy calendars or guides chart baby’s growth during pregnancy week by week. Though the baby continues to grow with every passing day, but changes and development of baby usually becomes manifest over a week’s time. Therefore, the complete pregnancy period has been divided into three trimesters comprising 40 weeks. By following the baby’s growth in pregnancy week-by-week information and or pregnancy calendars, you can have an idea as to what your baby looks like at a particular point in time. Moreover, if you find something lacking, you can get medical advice promptly. Let’s take a glance at some salient developments of your little one’s growth during the forty weeks.

The First Trimester

The first trimester of pregnancy week by week covers week 1 to week 14. First 2 weeks of this trimester denote the period from your last menses till conception or till that time when the sperm fertilizes the egg. By the end of week 3, the fertilized egg is metamorphosed into an embryo. During week 4 you begin to feel the early pregnancy symptom of nausea. Week 5 marks the beginning of formation of all major organs of the baby’s body. In fact this is the week, when the embryo’s metamorphosis into a baby begins. Come week 6 and your baby’s heart beats for the first time. Your baby doubles in size during week 7. By week 9, baby’s sex can be determined and your embryo becomes a small baby by week 10. Week 14 will make manifest another sign of pregnancy – enlarging and darkening of the area around your nipples.

The Second Trimester

The second trimester comprises week 15 to week 26. In the beginning of this trimester i.e. week 15, the baby begins movement of head, lips, and feet. Due to upward movement of uterus, the pregnancy symptom of frequent urination would abate by week 16. Baby begins blinking, sucking, and swallowing in week 17. Due to myelinization of nerves, nerve cell transmission registers a significant increase making body reflexes quicker. During week 20, baby begins to sleep and wake on regular basis. By week 24, baby’s heart beat becomes so distinct that it can be heard by placing an ear on stomach. And before the second trimester ends, brain wave activity commences for ears and eyes.

The Third Trimester

The third trimester as per pregnancy week by week commences with week 27 and ends with the birth of baby i.e. approximately week 40. Week 27 heralds increased movements of the baby. Senses of sound, smell, and taste develop by week 29. During week 34, baby’s own immune system begins to develop. Most of the babies are born around this period. By this week, look out for any signs of labor. In any case, your baby is born by the end of week 40. Sometimes, this period may extend by two more weeks.

By keeping yourself updated with the help of pregnancy week by week information, you can keep watch over various signs of pregnancy and your baby’s growth. If you feel your baby’s growth is not in consonance with the week by week chart, you can immediately get medical advice.

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