Your Baby's Development
This may sound strange, but you're still not pregnant!
Fertilization of your egg by the sperm will only take place near
the end of this week - read more about fertilization in the Your
Body section below.
Although you'll have to wait to find out what color to paint
the nursery, your baby's gender will be determined at the
moment of fertilization. Out of the 46
chromosomes
that make up a baby's genetic material, only two - one from the
sperm and one from the egg - determine the baby's sex. These
are known as the sex chromosomes. Every egg has an X sex
chromosome; a sperm can have either an X or a Y sex chromosome. If
the sperm that fertilizes your egg has an X chromosome, you'll
have a girl; if it has a Y chromosome, your baby will be a boy.
Your Body
Your uterine lining, which will nourish the baby, is developing,
and your body secretes follicle-stimulating hormone (FSH), which
stimulates an egg to mature. At the end of this week, you will be
at the midpoint of your menstrual cycle (if you have a regular
28-day cycle), and ovulation will occur (your ovary will release an
egg into the fallopian tube).
This is when you're most likely to conceive. If you have
sexual intercourse without protection around the time that you
ovulate, you can become pregnant. After your partner ejaculates,
millions of sperm travel through the vagina, and hundreds make it
to the fallopian tube, where your egg is waiting. One sperm
generally succeeds in penetrating the egg, and fertilization takes
place. When that happens, you will be pregnant - although you will
not be feeling any body changes just yet.
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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