Should women exercise when pregnant?

Should women exercise while they are pregnant?
Exercise and health experts say yes, they should.
Rotorua Zumba instructor Katrina Heywood  was recently criticised for doing Zumba while  six months pregnant with her third child.
She is no longer teaching her Zumba classes at this stage of her pregnancy but, once a fortnight or so, she has been supporting one of her Dance 2 Inspire colleagues while doing his class.
Last week she assisted one of her colleagues at the free Zumba at the lake front and, although most of the people there were supportive of her taking part while pregnant,  comment was made that it was inappropriate for her to be doing Zumba while pregnant and wearing clothes that showed her bump.
But Miss Heywood said she felt comfortable both in the clothes she was wearing and doing exercise at that stage in her pregnancy.
"I've always been active through my pregnancies," she said.
She consulted her doctor, who said it was fine to carry on exercising.
But she said she had toned down the exercise since she had been pregnant.
"I don't jump around any more.
"I'm still looking after the child I'm carrying."
Miss Heywood said she would rather be exercising than sitting around eating.
"I'm doing something positive to keep myself active."
She said other pregnant women needed to know their limits if they were exercising, and adapt the exercise to their condition.
Miss Heywood knows other women who continued with exercise while pregnant, but who  did only low-impact sports.
Director of Pilates Focus in Rotorua, Sandy Bird, agreed it was good to exercise while pregnant and said she kept exercising through both of her pregnancies.
"It's really important to keep your body moving during pregnancy."
She takes both pre-natal and post-natal pilates classes and said pilates could be good for both fitness and for correcting back pain caused by pregnancy.
Ms Bird's classes look at women's specific needs in each of the trimesters of their pregnancies and she takes into account each woman's case history to make sure they are not at any risk.
She said the stage when women continued exercising varied, with some finishing four weeks before and some carrying on right up to delivery.
Rotorua midwife Maureen O'Reilly said it was really important for pregnant women to exercise and there were few dangers.
But she said women should not take up a sport they were not doing before they were pregnant.
"If they were a sports person, they could carry on as before," Mrs O'Reilly said.
"I've known women who have done running up to seven months."
But she stressed that women needed to listen to their bodies and make sure they were not overdoing it.
She also said pregnant women needed to wear a decent sports bra and tummy support as they got bigger.
She warned that, as a pregnancy progressed, a woman's centre of gravity changed and, due to hormones,  joints and ligaments would get looser, so women needed to be aware of that and slow their exercise down.
Mrs O'Reilly suggested walking, aqua jogging, swimming and yoga as good low-impact sports for pregnant women, and they could do it right up to birth.
But overall she said women should not be worried about exercising.
"It's no more dangerous, as long as you are comfortable and take it quietly, than any other exercise would be."
Rotorua health coach, midwife and pregnancy treatment specialist Marta Sik says there are many benefits to exercising while pregnant.
She said exercise could help reduce every day stress, which could help women sleep.
She said it could also reduce pregnancy discomfort and help the body to get rid of aches and pains, ease backache and improve blood circulation.
It could also help to balance hormones and give women some positive self-esteem.
"It feels good when you know you did something for your health," Miss Sik said.