Stages of Pregnancy Development Month-by-Month (2023)

FAQs

What are the pregnancy developmental stages? ›

The process of prenatal development occurs in three main stages. The first two weeks after conception are known as the germinal stage, the third through the eighth week is known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.

The first trimester is the most crucial to your baby's development. During this period, your baby's body structure and organ systems develop. Most miscarriages and birth defects occur during this period. Your body also undergoes major changes during the first trimester.

Month 1 (weeks 1 through 4)

As the fertilized egg grows, a water-tight sac forms around it, gradually filling with fluid. This is called the amniotic sac, and it helps cushion the growing embryo. During this time, the placenta also develops.

Weeks 0 to 6

These early weeks mark the highest risk of miscarriage. A woman can have a miscarriage in the first week or two without realizing she's pregnant. It may even seem like a late period.

You're most fertile at the time of ovulation (when an egg is released from your ovaries), which usually occurs 12 to 14 days before your next period starts. This is the time of the month when you're most likely to get pregnant.

A fetal heartbeat may first be detected by a vaginal ultrasound as early as 5 1/2 to 6 weeks after gestation. That's when a fetal pole, the first visible sign of a developing embryo, can sometimes be seen. But between 6 1/2 to 7 weeks after gestation, a heartbeat can be better assessed.

Just four weeks after conception, the neural tube along your baby's back is closing. The baby's brain and spinal cord will develop from the neural tube. The heart and other organs also are starting to form. Structures necessary to the formation of the eyes and ears develop.

In these early weeks of pregnancy, the embryo is attached to a tiny yolk sac that provides nourishment. A few weeks later, the placenta will be fully formed and take over the transfer of nutrients to the embryo. The embryo is surrounded by fluid inside the amniotic sac.

What develops in the first 2 weeks of pregnancy? ›

Between the first and second week of conception, the blastocyst attaches into the uterine lining, thus beginning the embryonic stage. After these first weeks of fetal development, basic growth begins, as the brain, spinal cord, heart and gastrointestinal tract begin to form.

For a lot of people, the first sign of pregnancy is a missed period. Most pregnancy tests will be positive by the time you've missed your period. Other early pregnancy symptoms include feeling tired, feeling bloated, peeing more than usual, mood swings, nausea, and tender or swollen breasts.

During the third trimester, your fetus continues to grow in size and weight. The lungs are still maturing, and the fetus begins to position itself head down. By the end of the third trimester, the fetus is about 19 to 21 inches long and weighs, on average, 6 to 9 pounds.

These components are grouped into 4Ps: power, which refers to uterine contractions and maternal pushing efforts; passage, which refers to the maternal pelvis that the baby passes through during labor; passenger, which refers to the fetus and placenta; and psyche, which refers to the client's psychological status during ...

More than 80% of miscarriages occur within the first 12 weeks of pregnancy. After 12 weeks, the rate decreases rapidly (Dante et al, 2013; Houry and Salhy, 2014).

You'll likely notice the first signs of a bump early in the second trimester, between weeks 12 and 16. You might start showing closer to 12 weeks if you are a person of lower weight with a smaller midsection, and closer to 16 weeks if you're a person with more weight.

Some health conditions can cause a miscarriage

Certain types of uterine infections and sexually transmitted infections (STIs) can also play a role. Problems with the uterus or cervix such as fibroids and cervical insufficiency, which is when the cervix dilates too soon during pregnancy, can also lead to miscarriage.

Which trimester is high risk of miscarriage? ›

Most miscarriages happen in the first trimester before the 12^th week of pregnancy. Miscarriage in the second trimester (between 13 and 19 weeks) happens in 1 to 5 in 100 (1 to 5 percent) pregnancies. As many as half of all pregnancies may end in miscarriage.

The fetal brain begins to develop during the third week of gestation. Neural progenitor cells begin to divide and differentiate into neurons and glia, the two cell types that form the basis of the nervous system. By the ninth week, the brain appears as a small, smooth structure.

Your Baby's Development at 8 Weeks

At 8 weeks, a baby is typically between 1/2 and 3/4 inch long (1.5 to 2 centimeters),1 about the size and shape of kidney bean. Some parents even nickname their baby "the little bean" around this time, especially after catching a glimpse of the baby on an early ultrasound.

At this stage, the only things you'll likely see are the yolk sac and the gestational sac. It's possible that the sonographer might be able to point out the embryo, which at this stage is likely a tiny white curled object. Surrounding the embryo is the yolk sac, which will look like a small white circle.

What Happens at 3 Months of Pregnancy? 12 Weeks Pregnant.

How Big Is Your Baby When You're 3 Months Pregnant? At the start of this month your baby will be about ½ an inch long, and by the end of this month she'll be almost 2 inches long and weigh about ½ an ounce.

Your baby, or embryo, is about 2mm long (about the size of a poppy seed) and growing rapidly in your womb. It's protected by an amniotic sac, which is filled with cushioning fluid, and attached to a tiny yolk sac that provides all the nourishment it needs.

Your baby's nervous system is already developing, and the foundations for its major organs are in place. At this stage, the embryo is around 2mm long.

At 4 weeks pregnant, baby is smaller than a poppy seed—practically microscopic. Baby is now known as a blastocyst, a teeny ball of cells, and is busy settling into their new home (your uterus), prepping for all the crucial development that will happen over the next six weeks.

Your weeks of pregnancy are dated from the first day of your last period. This means that in the first 2 weeks or so, you are not actually pregnant – your body is preparing for ovulation (releasing an egg from one of your ovaries) as usual. Your "getting pregnant" timeline is: day 1: the first day of your period.

What happens in week 1 and 2 of pregnancy? ›

Gearing up to ovulate

But in weeks 1 and 2 of pregnancy — the week of and immediately following your last menstrual period — your body is working hard to gear up for the event that paves the way for baby: the big O, or ovulation.

4 weeks pregnant belly

You probably still won't look pregnant, so the cat's not quite out of the bag yet! Most first-time pregnancies don't show until around week 12. If you've had previous pregnancies you may show earlier as a result of stretching of the muscles in your uterus and belly.

The correct sequence in development is Fertilization → Zygote → Cleavage → Morula → Blastula → Gastrula.

Normal prenatal development lasts about 38 weeks and is divided into three stages: germinal, embryonic, and fetal. During these three stages of gestation, the original single-celled zygote develops into an embryo and then fetus [1, 2].

Our new Thrive philosophy is born from six stages of human development: social-emotional, intellectual, moral, psychological, physical, and spiritual.

After conception, your baby begins a period of dramatic change known as the embryonic stage. This stage runs from the 5th through the 10th week of pregnancy.

Infancy (neonate and up to one year age) Toddler ( one to five years of age) Childhood (three to eleven years old) - early childhood is from three to eight years old, and middle childhood is from nine to eleven years old.

But a lot is still happening. During the third stage of labor, you will deliver the placenta. How long it lasts: The placenta is typically delivered in 30 minutes, but the process can last as long as an hour.

What is the 5th stage of pregnancy? ›

The fifth week of pregnancy marks the start of the embryonic period. This is when baby's body systems and structures begin to form, such as the heart, brain, and spinal cord. Your baby's heart beats at a steady rate now, though it may not be detected by ultrasound for another 1 or 2 weeks.

1st stage of labour. During the 1st stage of labour, contractions make your cervix gradually open (dilate). This is usually the longest stage of labour. At the start of labour, your cervix starts to soften so it can open.