Research has found that underweight women are 72 percent more likely to experience a miscarriage in the first trimester when compared to women who had healthier BMIs.

By two months a baby’s neck muscles should have developed enough for them to support the weight of their own heads for short periods of time.

By 18 months, a baby should recognize the names of what other objects in the home or in his or her world are called. They may not be able to say the words independently, but should be able to point, pick up, or otherwise identify them.

Changes in your cervical mucus can signal when you are fertile. After your period has finished, your cervical mucus gradually increases in amount and changes in texture. This change reflects the rising levels of the hormone oestrogen in your body. It also shows you are close to ovulating.

It's widely known that folic acid (vitamin B9) reduces the risk of birth defects once you're pregnant, but some studies have also shown that women who take folic-acid supplements before becoming pregnant conceive at a higher rate.

Sufficient follicle stimulating hormone action is also needed for proper sperm production.