What is miscarriage

Defined by WHO (World Health Organization) as expulsion or extraction of a fetus or embryo weighing 500gm or less from its mother’s womb before 23 weeks of pregnancy. Overall, about 12–15% of clinically recognized pregnancies end in miscarriage, with the frequency increasing with rising maternal age.

Miscarriage and abortion are terms used interchangeably to describe a pregnancy loss in initial trimesters. However, most of the time the term miscarriage is attributed to an unplanned or spontaneous loss, whereas abortion is reserved for an induced termination of pregnancy.

Spontaneous miscarriage usually manifest with some form of vaginal bleeding with or without pain, it’s presentation may vary between individuals and between its types. When a pregnant lady in early trimesters with vaginal bleeding visits the doctor, an ultrasound scan is usually performed to confirm the diagnosis. Sometimes, the fetus has not completely aborted but her pregnancy is threatened, we call this threatened miscarriage. During the scan, the presence of a fetal heart beat would indicate that the pregnancy is still viable. A third of these threatened miscarriage will eventually progress and the pregnancy terminated. Depending on the type of miscarriage, surgery may be indicated.

For those who experience recurrent miscarriages, meaning 3 or more successive spontaneous miscarriage, investigation should be carried out to identify the cause. Thankfully, the risk of miscarriage reduces dramatically with each passing week and by the 7th week of pregnancy, less than 5% of pregnancy may be spontaneously aborted.

References:
http://apps.who.int/rhl/pregnancy_childbirth/antenatal_care/general/cd008679_mehtam_com/en/index.html
Definitions and indicators in family planning, maternal and child health and reproductive health. WHO Regional Strategy on Sexual and Reproductive Health. Geneva: World Health Organization, 2001.
Zinaman MJ, Clegg DE, Brown CC, O’Connor J, Selevan SG. Estimates of human fertility and pregnancy loss. Fertility and Sterility 1996;65: 503–509.