Second trimester

The Second Trimester The second trimester of pregnancy is when pregnant women often feel their best.

Second trimester

Breast tenderness is common during the first trimester, and is more common in women who are pregnant at a young age. Sometimes, timing may also use the fertilization age which is the age of the embryo.

Start of gestational age According to American Congress of Obstetricians and Gynecologiststhe main methods to calculate gestational age are: Early obstetric ultrasoundcomparing the size of an embryo or fetus to that of a reference group of pregnancies of known gestational age such as calculated from last menstrual periodsand using the mean gestational age of other embryos or fetuses of the same size.

If the gestational age as calculated from an early ultrasound is contradictory to the one calculated directly from the last menstrual period, it is still the one from the early ultrasound that is used for the rest of the pregnancy. Estimated date of confinement Due date estimation basically follows two steps: Determination of which time point is Second trimester be used as origin for gestational ageas described in section above.

Adding the estimated gestational age at childbirth to the above time point. Second trimester on average occurs at a gestational age of days 40 weekswhich is therefore often used as a standard estimation for individual pregnancies.

Naegele's rule is a standard way of calculating the due date for a pregnancy when assuming a gestational age of days at childbirth. The rule estimates the expected date of delivery EDD by adding a year, subtracting three months, and adding seven days to the origin of gestational age.

Second trimester

Alternatively there are mobile appswhich essentially always give consistent estimations compared to each other and correct for leap yearwhile pregnancy wheels made of paper can differ from each other by 7 days and generally do not correct for leap year.

A study of singleton live births came to the result that childbirth has a standard deviation of 14 days when gestational age is estimated by first trimester ultrasoundand 16 days when estimated directly by last menstrual period.

Human fertilization Fertilization and implantation in humans Through an interplay of hormones that includes follicle stimulating hormone that stimulates folliculogenesis and oogenesis creates a mature egg cellthe female gamete. Fertilization is the event where the egg cell fuses with the male gamete, spermatozoon.

After the point of fertilization, the fused product of the female and male gamete is referred to as a zygote or fertilized egg. The fusion of male and female gametes usually occurs following the act of sexual intercourse. Pregnancy rates for sexual intercourse are highest during the menstrual cycle time from some 5 days before until 1 to 2 days after ovulation.

Fertilization conception is sometimes used as the initiation of pregnancy, with the derived age being termed fertilization age. Fertilization usually occurs about two weeks before the next expected menstrual period. A third point in time is also considered by some people to be the true beginning of a pregnancy: This is time of implantation, when the future fetus attaches to the lining of the uterus.

This is about a week to ten days after fertilization. Development of embryo and fetus The initial stages of human embryogenesis The sperm and the egg cell, which has been released from one of the female's two ovariesunite in one of the two fallopian tubes.

The fertilized egg, known as a zygotethen moves toward the uterus, a journey that can take up to a week to complete. Cell division begins approximately 24 to 36 hours after the male and female cells unite.

Cell division continues at a rapid rate and the cells then develop into what is known as a blastocyst. The blastocyst arrives at the uterus and attaches to the uterine wall, a process known as implantation. The development of the mass of cells that will become the infant is called embryogenesis during the first approximately ten weeks of gestation.

During this time, cells begin to differentiate into the various body systems. The basic outlines of the organ, body, and nervous systems are established. By the end of the embryonic stage, the beginnings of features such as fingers, eyes, mouth, and ears become visible.

Also during this time, there is development of structures important to the support of the embryo, including the placenta and umbilical cord.Tia Mowry is bumpin’ along in her pregnancy!

The Sister, Sister alum — who is expecting her second child with husband Cory Hardrict — showed off her baby bump on Instagram Tuesday with a.

Second trimester

A woman’s body continues to change in the second trimester of her pregnancy. The second trimester is often defined as weeks 13 through During this time, your baby continues to grow and develop almost daily. Sep 17,  · When does the second trimester start and end?

Fetal development: The 2nd trimester - Mayo Clinic

The second trimester starts in week 14 of pregnancy and lasts through the end of week Baby's growth in the second trimester. Your baby is very, very busy in the second trimester.

By week 18 of pregnancy, he weighs about as much as a chicken breast, and can even yawn and Whattoexpect. Fetal development: The 2nd trimester Fetal development takes on new meaning in the second trimester. Highlights might include finding out your baby's sex and feeling your baby move.

Braxton Hicks contractions are described as the contractions that occur before real labor.

Second Trimester: Weeks 14 through 27 of Pregnancy | What to Expect

Braxton Hicks can begin as early as the second trimester. A miscarriage in the second trimester is a pregnancy loss that happens specifically between 12 and 20 weeks of gestation. (After this time, the loss is more accurately classified as a stillbirth or neonatal death.)No matter the timing, it's only natural to want answers when such an event occurs.

Second trimester: weeks 13 to 28 | Tommy’s