Getting your baby used to water early in his life makes sense from a safety point of view. Swimming is also great fun and good exercise. Start by getting your baby used to the water.
Learning to enjoy the water with your baby will strengthen the bond between the two of you as well as making you feel more positive about swimming.
When can you start swimming with your baby? Baby can go swimming at any time from birth.
Human babies demonstrate an innate swimming or diving reflex from birth until the age of approximately six months. Babies immersed in water will spontaneously hold their breath, slow their heart rate, and reduce blood circulation to the extremities such as fingers and toes. During the diving reflex, the infant's heart rate decreases by an average of 20%.
Pros of infant swimming lessons. In a 2009 study, participation in formal swimming lessons was associated with an 88% reduction in the risk of drowning in 1- to 4-year-old children, although the authors of the study found the conclusion imprecise. Another study showed that infant swimming lessons may improve motor skills.
http://catstreets.blogspot.com/2014/11/mother-and-baby-swimming-underwater.html