If your first indication of pregnancy is the absence of your period, then any sign of blood during pregnancy is going to set the alarm bells ringing. Your immediate thoughts are sure to turn to miscarriage and the possibility that this could well be the end of the line. But hold on: while it's undeniable that some pregnancies do end in miscarriage, bleeding in pregnancy needn't mean disaster.
Surprisingly, one in four women bleeds during pregnancy and only about half of these women miscarry.
For some, bleeding in pregnancy is just a little spotting; for others it's more like a heavy period, and for a very few it's actually even worse - but the fact is, despite this, the pregnancy can still make it to full term.
If you have an ultrasound that shows a heartbeat between seven and 11 weeks, your chances of continuing the pregnancy are greater than 90 per cent.

What to do
Get yourself checked out: no matter how much blood you've lost, the best thing to do is see your doctor or midwife, or go to your hospital's A&E department (or early pregnancy unit, if there is one).
Here, you may be given an internal examination to check that your cervix is closed, or you may be given a scan to rule out ectopic pregnancy. They will also check the position of the placenta, and will want to find a foetal heartbeat.
You will be asked how much blood you've lost (it may be useful to keep soiled sanitary pads) and if you have experienced any pain (severe stomach cramps may be a sign of placental abruption, for example).
If all appears well, you'll be sent home, hopefully reassured. You may be advised to rest, and if you have lost a great deal of blood, it's a good idea to up your iron intake.

Reasons for bleeding
Often you will not be given an explanation for the bleeding, which can be frustrating, but as long as you and your baby are well, it's best not to worry.
These are the most common reasons given for bleeding in pregnancy, excluding miscarriage:

Implantation bleeding - at six to eight weeks, when the embryo implants into one part of the uterus, the remaining lining comes away, in much the same way as the entire lining comes away when you have a normal period.

Ectopic pregnancy - where the fertilised egg implants itself outside the uterus. If bleeding takes place, it will probably be accompanied by abdominal pain.

Placenta praevia - where the placenta fully or partially covers the entrance to the cervix. This is most likely to occur in the second and third trimesters - it will probably have been picked up at a scan and you will be monitored very closely.

Infections - a vaginal infection (such as a yeast infection or bacterial vaginosis) or a sexually transmitted infection (such as trichomoniasis, gonorrhea, chlamydia, or herpes) can cause your cervix to become irritated or inflamed, making it more susceptible to bleeding.

Cervical erosion - this can be caused by infections, childbirth, use of an IUD or oral contraceptives; during pregnancy the cervix softens and is more susceptible to bleeding. As long as your smears have been normal, the erosion in itself is nothing to worry about; the bleeding should settle by the end of the first trimester.

Cervical polyp - a benign growth. Because of the increased flow of blood to this area, if you have any polyps, they are more susceptible to bleeding, leading to 'spotting'.

Haematoma or bleeding bruise - this is rare, but can be scary as there may be quite a lot of blood.

Note: if you bleed during pregnancy and are rhesus negative, you should be offered anti-D to prevent your body forming antibodies against any fetal blood that my have got into your bloodstream.

For more support on ectopic pregnancy, check out the Ectopic Pregnancy Trust website.
You can get valuable support from the Miscarriage Association if you ever need it.