Once a baby has been conceived, the mother’s body starts to go through some dramatic changes – all aimed at producing the best possible conditions for the embryo to grow. These changes are controlled by a number of powerful hormone signals.
When the fertilized egg implants in the lining of the, the usual pattern of hormone control that produces the menstrual cycle is disrupted. Normally, the level of the hormone progesterone would gradually fall off in the last two weeks of the cycle; however, part of the fertilized egg starts to produce a hormone [human chorionic gonadotropin HCGJwhich stimulates the ovary to continue excreting a high level of progesterone. This actually stops you ovulating again, now that the has begun.
Progesterone levels are very high in early, but the other major hormone involved, oestrogen, doesn’t rise so quickly. A certain base level continues to be excreted by the ovaries, but it rises more significantly later on, around the 12th to 14th week. At this stage, the developing placenta and embryo act together in taking over the production of both progesterone and oestrogen.
Is it true an increase in breast size is one of the first signs of pregnancy? Yes — it’s noticeable very early on. A woman may sometimes experience a feeling of fullness in the breasts even before she realizes she is pregnant. The size of the breasts increases with amazing speed, and by the 6th week of pregnancy (two weeks after your missed period) they will be very noticeably enlarged. The hormone prolactin, produced by the pituitary, causes the milk-producing glands in the breasts to get bigger, and this continues gradually throughout the pregnancy.
Most other changes in the breasts become noticeable at about the same time. Because the skin is stretched you may find they are unusually tender at this stage and an increased flow of blood through the breasts makes them tingle and throb. Don’t be surprised if you see lots of little surface veins appearing; this is also due to the increased blood supply.
The nipples will usually become more pro-minent and, in a first pregnancy, little white bumps will appear on the the pinky-brown area round the nipple. Some women again experience tender breasts in the last few weeks, combined with a leaking fluid from the nipple. This fluid is called ‘colostrum’ and is a normal and healthy sign.
The precise reasons are not known, but it’s probably due to one of the hormonal changes. There is a rapid rise in the production of variousin early pregnancy, but the high level of the hormone gonadotrophin is much reduced by the third or fourth month – and this is when most women start to feel sick. So it seems there could be a link between this hormone and the sickness.
The sickness may be partly ‘psychological’; this is not to say that anyone who is being sick is not looking forward to having her baby- simply that some of the natural anxiety a woman feels at this time shows itself through sickness.
Sickness affects about twothirds of pregnant women, in the early months. For quite a few expectant mothers it’s nothing more than a feeling of nausea when they wake up in the morning. Others may go on feeling sick at intervals throughout the day and some women actually vomit. Eating a dry biscuit or cracker before you get up in the morning does seem to help a lot of women- no one knows exactly why. Although being sick is inconvenient and un-pleasant there is no cause for alarm. Occasional vomiting cannot harm the baby or cause a, as some women fear.
Most women are totally unprepared for the tiredness that results from all the increased hormonal activity. The baby is still relatively tiny by the end of the first three months, and die tiredness seems out of all proportion to the actual ‘weight5 they are carrying. But in fact there are many other body changes going on in this time – besides what’s happening in theitself- all of which can contribute to a general feeling of fatigue.
One important change is in the pattern of blood supply. The pelvic area, containing the womb, aemands more blood to ensure rich supplies of oxygen and nutrients for the developing embryo. If this results in a decrease in blood supply to the mother’s brain, it may make her feel faint However, the sense of dizziness usually passes by mid-pregnancy, when the body has adjusted to the new pattern of blood supply.
There’s another major change which can contribute to general tiredness. The progesterone levels cause a softening of the ligaments that support the joints; this has a slightly weakening effect on the major muscles, so many activities can feel like much more of an effort than usual. The whole point of this ‘loosening’ is to allow the pelvis to expand to accommodate the baby, and make it sufficiently wide for theand delivery .
The womb in its normal state is slightly smaller than your clenched fist; by stretching of the inside cells it will gradually enlarge to hold a seven-pound baby plus placenta at full term. It enlarges quite slowly until the twelfth week, when it is usually about the size of a grapefruit At this stage it becomes too large to remain hidden in your pelvis and it can be felt through the abdominal wall.
Just when others will notice you are pregnant depends on the strength of your tummy muscles. If they have been kept strong by regular exercise, the muscles may act like a very good corset and hide the growing womb until about the 20th week. Also, if it’s your first child, your muscles may hide the growing child for longer. If they’ve been stretched by previous pregnancies you may be noticeably pregnant as early as the 14th week. However tf s an interesting point that your external size at full term doesn’t necessarily have much bearing on the size of your baby; both the amount of fluid surrounding the foetus and the strength of the tummy muscles may affect the overall size you reach.
Most women put on between 24-28lbs during pregnancy ana this is considered quite normal. As the baby usually only accounts for 6-9lbs of this, you may wonder how the rest is distributed.
The breasts and womb increase in size and therefore add to the weight of the baby itself; together with the amniotic fluid (which surrounds the baby) and the placenta, this comes to a total of around 15lbs. The natural increase in the volume of the mother’s blood accounts for some increase too, but the rest is due to increased body fat and fluid retention.
The increased level of oestrogen encourages fluid retention in the tissues, which may show as a slight puffiness in the ankles, fingers or face.
Most pregnant mothers retain some extra fluid in this way; it’s only a cause for concern if it rises too dramatically.
You may start putting on more body fat -usually as a result of eating too much. Although a healthy, balanced diet is more important than ever, it’s a common misthat you have to start ‘eating for two’. This is not necessary, and if you start eating a lot more than you used to, any excess calories will normally go into store, not into the baby!
Overall a weight gain of between 26-28lbs is usually advised. Alter this you can expect your weight to remain fairly constant until the baby is born.
Why do some women get varicose veins in pregnancy? The surface veins on the legs are responsible for draining blood up towards the heart, and the main channel through which the blood has to 41b) J pass runs up through the pelvis. In late pregnancy, when the growing womb pressed on these veins in the pelvic area, it has the effect of’damming’ the blood back into the legs, causing the skin veins to become swollen. In addition, the hor-mones produced in early pregnancy have the effect or making the veins a little saggy. Many women who get mild varicose veins during pregnancy find they improve afterwards, although in some cases they do become a permanent problem. The same sort of trouble can affect the veins at the bottom of the rectum, which is why piles are also common in pregnancy.
Is it normal for moles and freckles to get darker during pregnancy? Yes. One of the pregnancy hormones tends to make skin cells containing dark pigments enlarge and anymarks, freckles, moles or scars will become darker after about the 14th week of pregnancy. Some women-more usually the fair-haired, thin-skinned type – develop a dark-coloured area over the cheeks on either side of the nose, sometimes rather like a butterfly shape.
At about the same time you may notice a dark line- the tinea nigra – developing on the middle of your tummy, from the navel downwards. This usually fades when pregnancy is over, though occasionally a trace of it may remain. The nipples and areola also become much darker after the 14th week but this is a change which is permanent in most women.
Apart from changes in pigmentation, many women notice their skin looks in exceptionally good condition during pregnancy, and some acne sufferers find their skin troubles clear upthough the effect is not necessarily permanent.
Is it common for a woman’s sense of smell and taste to alter? Yes. This happens to nearly all women and is often another very early sign that you may be pregnant. It’s thought that the reason why many women suddenly complain of a’metallic’ taste in the mouth, and start to ‘go of? Things they’ve always liked, is due to an alteration in the blood supply to the lining of the nose and tongue. Both the sense of taste and smell seem to change, and many women can’t bear coffee,, cigarette smoke, or spicy foods.
It’s not unusual to develop a special craving for certain foods – like shellfish, pickles, or dough-nuts. Some women develop a really bizarre appetite, craving for something that’s not normall thought of as food.