Why we are Wonder Women

What our busy bodies can manage during pregnancy and beyond is astounding. Dr Nick Walker explains the changes.

The time of pregnancy, birth and beyond encompasses a really broad range of new experiences, not just socially and psychologically, but physically too! You and your body will undergo many obvious, and some not-so obvious, changes: read on to find out a bit more…

HORMONES AT WORK
The developing placenta produces copious hormones from week four. As we all know, each human being shares general similarities with others, yet also has unique differences, such as hair, skin and eye colour, facial shape, fingerprints and personality. Due to our genetic variations, these unique differences are also seen in each developing baby and in each developing placenta. This subtle variation gives rise to differing types, levels and proportions of placental hormone production, creating different symptoms and side effects. This is the reason that a woman may experience such different physical (and emotional) pregnancy-related changes during and amongst her pregnancies.

A few ‘lucky’ women will experience zero pregnancy side effects and only know they’re pregnant due to missed periods and a positive test or scan! However, most women will notice anything or everything from a very long list, including (but not limited to) nausea, vomiting, bloating, constipation, elevated or depressed mood, a heightened sense of smell, food cravings, lethargy, dry skin, loss of appetite, libido change, ptyalism (excessive mouth-watering), acne, vaginal discharge and/or thrush, frequent urination, headaches, dizzy spells, diarrhoea, varicose veins, leg swelling, vocal changes, sciatica, heartburn, nocturnal leg cramps…

Some of the links between these symptoms and the hormones responsible for them are well understood, but many remain unexplained or only partially explained. One of the main groups of hormones produced is called progestogens, and they aim to relax the uterine muscle, allowing muscle fibres to expand and stretch. Without these vital progestogens, the uterus would quickly contract and expel the pregnancy. However, the relaxing effect of the progestogens also has side effects, and these include:

1. Blood vessel walls relax, resulting in a tendency for varicose veins and haemorrhoids. These effects are also exacerbated by the several extra litres of blood in your circulation during pregnancy.

2. The lower sphincter of the gullet relaxes, causing a tendency for stomach acid to rise into the throat, creating the sensation known as heartburn.

3. The stomach slows down, resulting in a delay of the transit of food, made worse by the growing bump below, and exacerbating any tendency to nausea.

4. large bowel slows, a major factor in causing constipation – which then links back to the tendency to get those aforementioned haemorrhoids!

Other pregnancy hormones prepare your body for breastfeeding by promoting the growth of the individual milk production sacs and ducts. In actual fact, the breast growth and development that occurred during your puberty represents only a halted stage which is finally completed during your first pregnancy. Importantly, some hormones withhold milk production – because producing milk all the time would be a waste of energy. After the birth of the baby and the placenta, the lowering of these hormones initiates milk production for your new infant, just in time, around three days later.

THE ROAD TO RECOVERY
Things take time to resolve postpartum, and some physical characteristics may never return to their pre-pregnancy state.

The stretched skin which lay over the uterus and baby will not suddenly rebound, nor will the soft organs fall into the space created by their absence: in short, you’ll still look a bit pregnant. This effect differs markedly between women, due to the natural elasticity of different skin types, and the variability in the size of the bump to start with. Stretch marks may have occurred, and these may fade or may remain as a contrasting skin tone for many years to follow. This is very unpredictable and also depends on the woman’s skin type and its response to the placental hormones. This is why stretch marks differ between women, and even between pregnancies experienced by the same woman – obviously every woman is ‘stretched’ by pregnancy, it’s only the ‘marks’ that are unique.

Postpartum swelling of the legs and feet is almost universal, as extra pregnancy fluid has nowhere else to go, so follows gravity. This will take around two weeks to dissipate and neither walking nor resting will make it go away any sooner.

After a vaginal birth, the pelvic floor muscles and ligaments are often strained and loosened due to the passage of the head of the baby. This effect may be worsened in the case of assisted birth by ventouse or obstetric forceps, but will nonetheless occur to some degree with any vaginal birth. This loosening may be uncomfortable, but what is most often noticed is the unusual behaviour of your bladder, which may emit urine without you knowing or being able to control it. Some women may experience the opposite problem, finding it difficult to feel a ‘full’ bladder, and will need to consciously visit the toilet regularly. Over the subsequent weeks, as with any soft-tissue sprain or strain, your body is usually able to heal and restore itself back to normal functioning levels. Bowel control is less commonly an issue, and it’s vital you report any problems of this nature to your maternity caregiver, as it’s never normal to have no control over your faeces or flatulence. Postpartum vaginal bleeding (known as lochia) will always occur, and although fair-sized blood clots may be passed, the presence of heavy or non-stop bleeding should trigger an urgent check up. The placenta that was attached to the uterus wall left a large, raw surface there when it separated at birth. This is the source of the bleeding, and while the uterus shrinks from its immediate post-natal size (over about three weeks) the bleeding is most noticeable. In some cases, a small amount of placenta remains attached – this may be a cause of prolonged bleeding beyond the usual three- to four-week time frame. Vaginal bleeding can also be from tearing during the birth process. These wounds will usually take just one or two weeks to heal, but if pain or bleeding from vaginal or perineum skin wounds is prolonged, they should be checked by your maternity care provider.

KEEPING ABREAST
The breasts undergo yet more changes postpartum. Milk production, initiated by both the falling pregnancy hormones and the presence of a suckling baby, ramps up between two and four days after birth. While awaiting these days, your baby will suckle an early breast secretion called colostrum, which is a low-volume but high- energy fluid that has been accumulating in the breasts during pregnancy. The arrival of the milk is usually not subtle: you’ll notice a sudden heaviness and fullness over a very short time. Pain and redness during this time can be a sign of milk leaking from the ducts and into the breast tissue, which can lead to mastitis, so be sure to let someone know if you notice that. The nipples themselves have often darkened in colour during your pregnancy, and enlarged, both of which make your breast an easier target for your new baby! Having undergone these innate transformations, the baby’s suckling further alters your breasts, elongating and toughening the nipples due to constant feeding. This is why breastfeeding subsequent babies is often easier, because these changes become nearly permanent.

OUR NEW NORMAL
Menstrual cycles may resume at some stage – this one is really unpredictable from woman to woman. Breastfeeding acts somewhat as an ovulation and menstrual cycle inhibitor, though it’s by no means a reliable form of contraception (for advice on this you should ask your LMC or family doctor). Fortunately, most common birth control methods are fully compatible with breastfeeding. In relation to loss of regular menstrual function and lack of ovulation, the relatively flat postpartum hormones can lead to a state of semi-menopause, including hot flushes and vaginal dryness.

Behind these obvious bodily changes, more subtle things are also happening. Enlarged during pregnancy to cope with the extra demand, your heart will take around six months to return to normal size and function. Your pelvic floor takes four to six months to ‘bounce back’ to normal, however a degree of laxity may well be permanent. Your scalp and body hair is shed more slowly in pregnancy, and postpartum you may experience a sudden loss. Don’t be alarmed – it’s really just catching up from nine months of reduced turnover.

However you experience the changes in your body, be sure to enjoy the good parts, take lots of photos, and reflect on what a remarkable feat it is for your body to set a new human being on their own life journey.

Dr Nick Walker is a specialist obstetrician working in both public practice at National Women’s Hospital and private practice in Mt Eden, Auckland. He divides his time between these roles and helping his wife in caring for their four young children.