Fundamental hormonal changes take place during pregnancy. Future mums release a hormone, cortisol, which decreases the amount of collagen in the skin and helps to keep skin fibres stretchy. This isn't good news, as it takes place at the same time that skin is stretching due to weight gain and baby's growth!
How to prevent stretch marks
The main risk to your skin is the appearance of stretch marks, especially during the third trimester. These purple lines fade to silvery-white after birth but they never completely disappear, so the ideal solution is to prevent them appearing in the first place.
Moisturise and soften your skin. Apply anti-stretch mark cream or moisturiser both morning and night using circular motions, mainly over your stomach (not forgetting the bottom of the stomach and the belly button!), and also over your hips, breasts and bottom. Avoid putting on weight too quickly: this is the best method of prevention.
Use collagen, elastin, Vitamin A & E-based creams and apply them regularly.
Not putting on too much weight will also help limit stretch marks. Remember, the younger your skin is, the more fragile it is, so if you're under 26 you really need to be slapping on anti-stretch mark creams and nourishing oils! To further increase their effect, use a body scrub once a week. It will make your skin more resistant and help your skin absorb the active ingredients.
Reducing stretch marks through exercise
During the first three months, you can do stretching and gym exercises (provided you don't work your abs too hard). Then, as your pregnancy progresses, take up water sports: swimming or aqua-aerobics are fine right up to the end and they're excellent all round for the body. For your wellbeing, try walking, yoga and Pilates.
Other essentials for your skin: lots of water, fruit and vegetables, and sun protection whenever you're exposed.