At around week 16, an unborn baby’s aural structures are quite well developed. He or she should be able to detect some noise, though it will be restricted to the inner noises of mom’s body. By week 24, he or she will be able to hear noises outside the womb, and may respond to mom or dads voice.

Within the uterus, the foetus is very well protected by their amniotic sac. This means that accidental blows to the stomach, or even a minor car accident should not cause any major damage to the foetus, let alone a miscarriage.

By six months old a baby’s muscles should have strengthened, and they should have mastered the ability to roll over, even several times at once.

Most women hit their fertile peak between the ages of 23 and 31, though the rate at which women conceive begins to dip slightly in their late 20s.

Some men have an immune reaction to semen, which causes them to produce anti-sperm antibodies that damage their sperm.

Retrograde ejaculation may cause infertility. However, semen can often be removed from the bladder and used during assistive reproductive techniques to achieve a pregnancy.