Your doctor may advice you to send some of the tissue removed at the time of abortion to lab for analysis. The result can confirm if pregnancy was inside the womb and not an ectopic pregnancy (when it grows outside the uterus). It also checks it for any abnormal changes in the placenta like molar changes. This test is useful especially in very early pregnancy when ultrasound may not be very useful for visual detection of the above conditions.
If you miscarry at home, you may bring any tissue which has been expelled for analysis. If you have been having repeated pregnancy losses (say more than three in a row), your doctor may advise further testing like karyotyping on the tissue.
However, if the pregnancy was reasonably grown and the baby was clearly visible inside the womb, you may omit any kind of testing after duly understanding the consequences. The clinic might want your consent to avoid sending tissues for analysis.
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