Human hair growth
The three stages of hair growth are the anagen, catagen, and telogen phases. Each strand of hair on the human body is at its own stage of development. Once the cycle is complete, it restarts and a new strand of hair begins to form. The rate or speed of hair growth is about 1.25 centimetres or 0.5 inches per month, or about 15 centimetres or 6 inches per year.
Hair care
During pregnancy and breast feeding, the normal and natural shedding process is typically suspended (starting around month three because it takes a while for the body to recognize and reset for the hormonal shifts the body goes through) for the period of gestation and extended longer if one breast feeds (this includes pumping for breast milk). Upon cessation of either of these, it typically takes around two months for the hormones to shift again to the normal hormonal settings, and hair shedding can increase exponentially, for approximately 3–6 months until hair returns to its normal volume. It is commonly noticed that hair seems thicker and shinier, even, during pregnancy and breast feeding in response to the influx of shifting hormones. It is not unusual also for hair color to change, or hair structure to change (e.g., straighter hair, curlier hair). These changes can occur more often than people may realize yet isn't often reported.