Some unlucky women experience the onset of morning sickness earlier, at around 4 weeks, but on average women will start to experience the symptoms of morning sickness at week 6.

All of the above anomalies can result in irregular periods following a miscarriage.

Bleeding in the early days of pregnancy is common, and is unlikely to harm your baby. About one in five mums-to-be have some bleeding in the first three months of their continuing pregnancy. It usually happens at about the same time that your period would have been due, and may last for a day or two.

Ultrasound scans are a fairly accurate way of determining your baby's sex from about 18 weeks of pregnancy.

This extra tissue growth — and the surgical removal of it — can cause scarring, which may obstruct the tube and keep the egg and sperm from uniting.

Scarring or abscesses in the fallopian tubes can make it difficult for you to get pregnant if eggs cannot pass easily into the womb.