Your 2nd week
THIS IS DAY 8 OF YOUR MENSTRUAL CYCLE
272 days to go...
WHAT’S HAPPENING INSIDE ?
Here, three developing ovarian follicles can be seen in white. The inner circle of
each is the egg. Of the follicles shown, it is likely that only one will fully mature
at ovulation (see p.49) and release an egg.
By the end of this week you’re likely to have ovulated. It’s a good
idea to know the signs that indicate you’re at your most fertile.
This is week two of your cycle.
You will probably ovulateby the end of
this week and will therefore be fertile.
However, the fertile window can be from
5 days before ovulation to 12–24 hours
after as sperm can survive for 5 days
inside you. If your periods are regular,
ovulation can be easier to track, but you
may want to use other methods, such as
looking out for natural signs (see box,
right) or using an ovulation kit.
Remember, however, the best way to
conceive is to have sex regularly.
While they are useful, testing kits are
expensive and can be counterproductive
because they make sex more clinical and less enjoyable. They work by testing
the urine to detect a surge in LH, the
hormone that triggers egg release.
Always follow the instructions given.
Testing between 10 am and 8 pm should
be fine, but try to aim for roughly the
same time every day. After a positive
test, you should ovulate 12–36 hours
later. Results are about 99 percent
accurate but occasionally the result is a
false positive. Results can occasionally
give a false negative, especially if you’ve
drunk a lot of water. If your test was
negative, do another one the next day.
Once you have a positive result, you can
stop testing for that month.
ARE YOU OVULATING?
This week, look out for:
- Lower abdominal pain at ovulation, called mittelschmerz (the German for “pain in the middle”).
- Basal body temperature (your temperature when you first wake in the morning) rising slightly.
- Cervical mucus—the cervix produces secretions, which become wetter, clearer in color, and stretchy, resembling raw egg white, just before ovulation. This indicates the start of your fertile phase.
THIS IS DAY 9 OF YOUR MENSTRUAL CYCLE
271 days to go...
WHAT’S HAPPENING INSIDE?
In your partner’s body, sperm is constantly being produced. Here the sperm cells
can be seen: they consist of a head (green), which contains the genetic material,
and fertilizes the egg, and a tail (blue), which propels the sperm along.
While you wait to ovulate, fascinating changes are occurring
in your ovaries as your follicles mature to release an egg.
In the time leading up to
ovulation, which will happen later
this week, the most advanced follicle
moves to the surface of the ovary, ready
to release its precious cargo. While you
were having your period, around 15–20
follicles were developing in your ovaries.
Both of your ovaries contribute to
follicle growth, but usually only one
ovary brings a follicle to ovulation.
Which ovary it is seems to depend on
chance since ovaries are not on a strict
rotation. As the follicles grow, they
enlarge greatly, filling with fluid secreted
inside the follicle. Some women release
more than one egg some months and if both are fertilized, it will
mean nonidentical twins are conceived.
By the time of ovulation, the follicle
will be about 1 in (2 cm) in diameter,
while the egg is just about visible
without a microscope.
To mature, follicles need FSH (folliclestimulating hormone) produced by the
brain’s pituitary gland, but
their early growth doesn’t appear to rely
on it. It may, however, depend on other
hormones and chemicals.
FOCUS ON... DADS
Dads: your diet counts too
It’s never too late to start eating
well if you want to become a dad. But
because sperm take some weeks to
mature, ideally start eating a healthy
diet at least three months before
conception. There are supplements,
but most vitamins and minerals work
better in the form of real food.
- Antioxidants A diet rich in antioxidants, including vitamins A, C, and E, selenium, and zinc, helps prevent damage to sperm DNA.
- Selenium may also help sperm penetrate the outer layer of the egg. Eat tuna, wheatgerm, whole grains, and sesame seeds.
- Zinc is present in large amounts in semen. Eat fish, lean meat, shellfish, turkey, chicken, eggs, whole grains, rye, and oats.
- Manganese is another element that could help male fertility. Eat leafy vegetables (including broccoli) carrots, eggs, whole grains, and ginger.
- Essential fatty acids may improve sperm motility. Eat oily fish, such as mackerel, salmon, and sardines, flaxseed and linseed, and kiwi fruit.
SPECIALIZED MEDICAL ADVICE
If you have any ongoing medical
problems, go to see your doctor
before you start trying to conceive.
Conditions such as diabetes,
asthma, high blood pressure, heart
trouble, a previous bout of deep
vein thrombosis (DVT),
thyroid conditions, sickle-cell
disease, and epilepsy can all impact
a pregnancy.
The effect will depend on the
individual condition and a specialist’s
advice and care will be needed. If
you’re in any doubt about how your
own medical history may affect a
pregnancy, check with your doctor
before you start trying to conceive
THIS IS DAY 10 OF YOUR MENSTRUAL CYCLE
270 days to go...
WHAT’S HAPPENING INSIDE ?
As ovulation approaches, more cervical mucus is produced. Here it has crystallized
to form a “fern leaf” pattern. Around the time of ovulation the mucus becomes clear,
slippery, and stretchy, which makes it easier for sperm to swim through.
You may not care whether you have a boy or a girl, but
according to some theories you can influence gender.
Conceiving is all about having
sex at the right time this week,
but if you’re hoping to have a child of a
specific gender, the timing could be even
more important. Some experts claim
there is a link between when you have
sex and the baby’s gender (see below).
Recent research suggests that women
who have a high calorie intake (especially
if they eat that most phallic of fruit, the
banana) are marginally more likely to
bear a boy. Those who skip breakfast or
have a low calorie intake are more likely
to have a girl. One reason for this is
thought to be that the extra calories
consumed affect vaginal secretions and
help to give the Y sperm that makes baby
boys a vital boost.
AS A MATTER OF FACT
If you already have two same-sex children, you’re 75 percent
more likely to conceive a child
of that sex again.
Although the sex of the baby
conceived is random, conceiving
children of the same sex could be
due to the fact that some men
produce better quality X sperm,
which makes baby girls, or Y sperm,
which makes baby boys.
Statistically, couples who have two
children of different sexes are less
likely to try for a third child
MAKING BABIES... BOYS AND GIRLS
The Shettles method, devised by Dr. Landrum Shettles, is
based on the fact that Y sperm (for boys) are smaller, faster,
and less resilient than X sperm (for girls), and are less able
to withstand an acidic environment in the vagina
To conceive a boy, the Shettles method advises:
- Timing sex as close to ovulation as possible and adopting positions such as rear-entry that promote deep penetration.
- The woman should orgasm, ideally at the same time as the man to make the vagina less acidic and favor Y sperm.
- Drinking a cup or two or strong coffee just before sex to give Y-sperm an added kick.
The Whelan method, devised by Dr. Elizabeth Whelan,
suggests that having sex earlier on in the cycle, some four
to six days before ovulation, is more likely to result in a boy.
Sex nearer the time of ovulation is more likely to result in a
girl. Curiously, the Whelan way is more or less the opposite
of the advice given by Shettles.
But what works? The mainstream medical view, supported
by reports in journals such as the New England Journal of
Medicine, is that the timing of sex has little or no bearing on
gender. The possible exception is that having sex two days
before ovulation may be slightly more likely to favor a girl.
THIS IS DAY 11 OF YOUR MENSTRUAL CYCLE
269 days to go...
WHAT’S HAPPENING INSIDE?
The lining of the fallopian tube, seen here, has a moist mucous membrane.
This contains cells (brown) that protect the tube’s surface. The hairlike cilia (blue)
move the eggs along the tubes following ovulation.
If this isn’t the first month you’ve been trying to conceive,
don’t be too disappointed. It’s normal for it to take some time.
Have you been trying for a
baby for some time? It’s hard
to face the fact that we don’t always
conceive when we want to. This lack
of success may be difficult to handle,
especially if you’re someone who has
achieved in other areas of your life.
With reproduction, there’s a large
element of chance. Even for young
women at their peak of fertility, the
odds of conceiving in any one cycle are
50–50. It’s not unusual to try for six
months, or even 12 months, without
success. Around 16 percent of couples
take over a year to achieve a pregnancy.
So plan for conception over a longer
time frame, say 12 months, unless
you have any specific reasons to be
concerned about your fertility or your
health in general.
The main exception is if you are over
30. In this case, see your doctor after
trying for about six months. The first
step is likely to be a blood test for you,
and a semen analysis for your partner.
However, be reassured that if you are
over 30, you may still get pregnant in
the old-fashioned way. The average time
taken for a 39-year-old woman to
conceive is 15 months. But the snag is
that if you do end up needing assisted
fertility techniques, it all takes time.
ASK A... NUTRITIONIST
I’ve heard that green tea will help
me conceive. Is this true? So far,
studies on green tea and fertility
aren’t conclusive one way or the
other. Overall, it’s likely to benefit
your health without affecting your
fertility. However, although green tea
has a host of health benefits, it
contains small amounts of caffeine
and tannic acid, both of which have
(at least in large quantities) been
linked to fertility problems and an
increased risk of miscarriage.
STOPPING CONTRACEPTION
You can get pregnant as soon as
you stop using some contraception.
- IUD (coil): you can get pregnant if you have sex in the week before it’s removed since sperm can live 3–5 days.
- Pill: assume you’re fertile immediately. Some women seem to be extra fertile after stopping the Pill.
- Implants: fertility can return immediately after removal of the implant, but some women find it takes longer. Occasionally periods can take three to nine months to become regular. This suggests that the effects of the hormone are still lingering, but you may still conceive.
- Injections: irregular bleeding can continue for months, and you may not be able to conceive for several months either. However, as with implants, it’s possible to get pregnant before your periods return properly.
- IUD or IUS: you could get pregnant if you have sex in the week before removal of the IUS system, but because the system contains progesterone, conception is less likely than with a regular coil (see left).
THIS IS DAY 12 OF YOUR MENSTRUAL CYCLE
268 days to go...
WHAT’S HAPPENING INSIDE?
This mature ovarian follicle contains a fluid-filled cavity (pale pink) known as the
follicular antrum. At this stage, just prior to ovulation, one follicle has become much
larger than the others, and it is this follicle that will rupture to release an egg.
As your hormone level rises around this stage of your cycle,
so might your libido—it seems nature takes care of everything!
Estrogen levels are rising and
reach their peak today, based
on a 28-day menstrual cycle. The rise
in estrogen from the follicles is what
stimulates the release of the LH
hormone, which surges
about 24 hours before ovulation. FSH from the pituitary gland starts rising later this week. Progesterone
levels are low. There’s no call for this
hormone until the uterus lining needs
to thicken. In fact, high levels would
make the cervix hostile to sperm, so
they would have trouble getting through
to the uterus and the fallopian tubes
to fertilize the egg.
Women also produce the male
hormone testosterone and this reaches
a peak around ovulation. This hormone
is responsible for libido in both sexes
so, hopefully, you and your partner
should find you’re both in the mood
for making babies at this time.
ASK A... DOCTOR
I had a miscarriage four weeks
ago. Is it safe to try for another
baby right away? There is no exact
advice on when you should try
again following a miscarriage. As
a general guide, wait until you’ve
had one menstrual period. This will
help to date the pregnancy should
you conceive quickly. However,
your doctor may advise otherwise,
especially if your miscarriage was
linked with an infection. If you
are waiting for tests because you
miscarried, it makes sense to
have these first.
You and your partner may
need time to grieve for the lost
pregnancy, so it is unwise to rush
into trying to conceive again. Be
reassured that the vast majority
of women who had a single
miscarriage go on to have a baby
AS A MATTER OF FACT
Being stressed can affect your
ability to conceive.
Perhaps it’s no surprise that nature
makes it more difficult to conceive in
stressful circumstances. One reason
might be that it reduces the ovary’s
response to the hormone surge at
mid-cycle (see left). There is also a
link between stress and the failure
of fertility treatments, although the
exact reason for this isn’t known.
It’s a good idea to talk about and work through your grief together before trying to get
pregnant again. Miscarrying can be extremely tough and may put a strain on your relationship
THIS IS DAY 13 OF YOUR MENSTRUAL CYCLE
267 days to go...
WHAT’S HAPPENING INSIDE ?
The sperm cell can be seen here inside the fallopian tube. Since sperm can stay
active and alive inside you for up to 72 hours, it’s possible to get pregnant even
if you don’t ovulate for two to three days from now
This is an optimum time to conceive, but try not to think too
much about when you might be ovulating and just enjoy sex!
AS A MATTER OF FACT
Having an orgasm could boost
your chances of conception.
One theory is that the female orgasm
is an evolutionary device designed
to convey semen into the cervix as
the uterus contracts. If the woman
climaxes up to a minute before her
partner, or she doesn’t orgasm, she
will retain less semen than if she
comes at the same time or after him.
Use the time around ovulation
to put some excitement and spontaneity
back into your sex life. With all the
recommendations and restrictions,
not to mention old wives’ tales, that
supposedly maximize conception
rates, it’s easy to forget that sex is
meant to be enjoyable.
If you’re hell
bent on conceiving, then the fun can
get forgotten. You might want to try
different positions, times, or places
for sex. If you and your partner aren’t
usually that adventurous, this is a good
opportunity to try varying things a little.
Try to have sex every 24–48 hours.
If
your partner ejaculates regularly, it will
encourage the production of quality
sperm. The benefits of abstaining have
been greatly overstated in the past.
It is
true that not having sex for up to seven
days can boost the number of sperm,
but research now shows that abstinence
can impair the motility (swimming
ability) of sperm, especially if the sperm
were already borderline. The longer the
period of abstinence, the more marked
the effect will be.
So have fun and if you
conceive that’s a bonus!
It may improve your chances
of conception if you lie down for
15–20 minutes after having sex.
Lying with your legs in the air
will aid gravity further.
SEXUAL POSITIONS
It seems that how you have sex
can help conception. Positions
that maximize penetration, such
as rear entry, may work best since
sperm is then deposited as close to
the cervix as possible—languishing
too long in vaginal secretions can
lead to a sperm’s early death. If
the man is on top, the woman
could try placing a pillow under
her buttocks to raise her pelvis and
aid the movement of sperm toward
the cervix. Woman-on-top positions
may lead to leakage of sperm. Avoid
using lubricants because they can
adversely affect sperm.
THIS IS DAY 14 OF YOUR MENSTRUAL CYCLE
266 days to go...
WHAT’S HAPPENING INSIDE ?
The ovary can can be seen here at the end of the fallopian tube. At around this time
of the menstrual cycle, a follicle at the surface of the ovary releases an egg, which
is swept down the tube by clearly visible fingerlike projections called fimbriae.
You’re highly likely to ovulate today, if you haven’t already,
and if egg meets sperm you may soon be pregnant.
Typically ovulation occurs
around day 14 but it can occur
earlier or later. Ovulation is when
an egg is released from your ovaries
(sometimes two eggs are released—see
box, below). LH rises thanks to estrogen
output from the growing follicles, and it is this rise that triggers
the events that now take place in the
follicle.
LH makes the egg inside the
follicle become fully mature, ready for
release and fertilization. This is the point
at which the egg reduces its number of
chromosomes from 46 to 23.
The follicle is rich with fluid by now.
Just before ovulation, it is some 1 in
(2 cm) or more in diameter. In position,
it lies just below the surface of the
ovary. If you could see the follicle, it
would look like a blister about to burst.
Next the follicle produces enzymes that
digest its outer layer, releasing the egg
on to the surface of the ovary.
Once the egg is released from the
follicle, it’s soon swept into the nearest
fallopian tube by the fingerlike projections
that form the end of the tube, where it
will hopefully be fertilized.
At ovulation, the follicle ruptures and the
egg breaks through the surface of the ovary.
Sometimes two follicles mature to this point,
both releasing an egg.
AS A MATTER OF FACT
If you’ve had nonidentical
twins already, your chance of
having another set quadruples.
Nonidentical twins occur when
more than one follicle ripens
completely and the two eggs
released at ovulation are both
fertilized. The increased chance
of having another set of twins is
because most women who conceive
nonidentical twins (without fertility
drugs) showa pattern of releasing
more than one egg per cycle. Your
chance of having a second set of
twins is about 1 in 3000.
FOCUS ON... RELATIONSHIPS
Pressure to conceive
If you’re trying to conceive, you
may have little else on your mind
and this can put a strain on your
relationship. With the goal of
pregnancy in mind, it’s easy to
become clinical about sex. At this
point, you and your partner may be
regarding each other not so much
as sex objects, but as components
of a baby-making machine.
Enjoyment can so easily get lost.
Understandably, you may
find that your partner becomes
aggrieved if he feels pressure to
provide sperm; the distress may
have an adverse effect on a man’s
willingness and even ability to have
sex. If this happens, it can lead to
a downward spiral, which naturally
makes conception less likely, and
may cause discord.
Make an effort to be loving
and work together rather than
against each other. Consider taking
a break; couples often conceive
when they’re away on vacation and
more relaxed. Make sure you also
enjoy some stress-free sex outside
of your fertile window.
Conception
Pregnancy begins with conception, a complex process that involves the
release of one or more eggs from the ovary, successful fertilization by a
sperm in a fallopian tube, and implantation in the lining of the uterus.
The release of an egg
Each woman is born with her full quota
of follicles that contain immature eggs,
some of which will mature and be
released in her lifetime. Every month,
follicle stimulating hormone (FSH),
released from the pituitary gland,
encourages a number of the follicles
to ripen. These follicles in turn produce
the hormone estrogen, rising levels of
which encourage the uterus to thicken
to prepare for the implantation of a
fertilized egg. As the eggs mature, the
level of estrogen rises and the pituitary
gland receives a message to produce
luteinizing hormone (LH). Every month,
this surge in LH triggers one follicle (and
sometimes more than one) to release a
mature egg—the moment of ovulation.
Once the egg leaves the ovary, it
enters the fallopian tube, which lies
close by, and starts to travel through the
tube to the uterus. The fallopian tube is
just 4 in (10 cm) long and its lining has
many tiny fronds that literally brush the
egg in the direction of the uterus. Even
so, the journey takes five days or
more. In the course of this voyage,
the fertilization of the egg takes place.
The journey of the sperm
During sex, the man releases an
abundance of sperm—around 250
million at each ejaculation—into the
vagina. Each sperm has a long tail
to propel it, so it’s well equipped to
swim up to the fallopian tube, where
fertilization of the egg takes place.
The whole distance, from the vagina through the uterus and up into the fallopian tube can be accomplished in hours. However, the sperm can survive in the vagina and the uterus for 3–5 days, meaning there is a window of around 6 days in which fertilization can take place (an egg lives 12–24 hours after ovulation).
Not all of the millions of sperm make it as far as the fallopian tube; in fact, most of them die, seep out of the vagina, or get lost along the way. Around just 200 sperm, only a tiny fraction of the number originally released, arrive at the site of the egg.
The moment of fertilization
Although many sperm cluster around
the egg and try to penetrate its outer
layer, only one of them will manage
to burrow its way through the surface
and fertilize the egg. Once this happens,
the egg’s outer layer thickens quickly
to keep out other competing sperm,
so that each egg can be fertilized by
only one sperm.
.
Implantation in the uterus
By the time the fertilized egg reaches
the uterus, it has grown from a single
cell into a compact cluster of cells,
called a blastocyst. This cluster attaches
to the uterine lining very loosely at first,
then more deeply and permanently.
At this early stage, the blob of cells,
which is more than just a fertilized egg,
but not quite an embryo, is sometimes
referred to as a “conceptus.” Although
its sex is already determined, it’s not
remotely baby-shaped yet. The cells
produce enzymes that allow it to digest
its way into the uterus lining, and lie
snugly below the surface.
Assisting conception
Some couples find that conception takes
longer than anticipated. If you haven’t
become pregnant after two years of
trying, your doctor may suggest fertility
testing to identify if your fertility or that
of your partner is suboptimal. If this is
the case, you may want to embark on fertility treatment to assist conception.
The most popular treatment is in vitro
fertilization, or IVF.
This involves taking
fertility drugs to help you produce more
eggs. The eggs are harvested and fertilized
with your partner’s sperm in a laboratory
(hence the term “test-tube baby”), and
you’re given hormone treatment to
prepare the uterus to receive the fertilized
eggs.
If the quality of sperm is poor, a procedure called intracytoplasmic
sperm injection, or ICSI may be used,
whereby a single sperm is injected
directly into an egg and the fertilized egg
is transferred to the uterus. Intrauterine
insemination, or IUI, involves putting
sperm that have been selected for
viability directly into the uterus. This is
used where sperm has poor motility, or
there are problems with ovulation.
TWINS
How twins are conceived
Today in the US, one in every 31
births is a twin birth. Twins are
conceived in two ways that result in
either identical or nonidentical twins.
Identical twins occur when one
fertilized egg splits into two separate
cells. This type of twin is half as
common as nonidentical twins.
Identical twins have the same genes
and are the same sex, so they are
very alike, although subtle differences
in their environment can mean
they’re not always identical in every
way. Identical twins are known as
“monozygotic” twins, since they come
from one “zygote," or fertilized egg.
Triplets, quads, and higher multiples
can be monozygotic too. However,
triplets and more can arise from more
TWINS
complex combinations. For example,
there may have been two fertilized
eggs, one of which split into two.
Nonidentical twins occur when
two eggs are released at ovulation.
Each twin’s genes comes from the
parents, but the twins don’t share
the same mix of genes. Nonidentical
twins are also called “fraternal” twins,
since they’re no more alike than other
siblings and can be of a different sex.
They’re also referred to as “dizygotic”
twins, because they come from two
separate “zygotes,” or fertilized eggs.
Nonidentical triplets arise when
three eggs are released instead of
one. This is more likely to occur when
ovulation is induced with drugs
during fertility treatment.
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