Vandana, sorry to hear about the miscarriages. Loss of fetus in three or more miscarriages is called recurrent miscarriage or Habitual Abortion. There can be many reasons for this. 1. Abnormal uterus is the most common cause. MRI & Laproscopy can reveal this. 2. Weak cervix is another common cause but the miscarriages due to weak cervix occur only in second trimester (after 3 months of conception). But in your case you have had early abortions. 3. Hormonal problems like thyroid problems, uncontrolled Diabetes Mellitus, Poly Cystic Ovarian Syndrome could also result in repeated abortions but these cannot be the reason for you as they could have been diagnosed by now. 4. Infections like measles, toxoplasmosis & cytomegalovirus can cause a single miscarriage & not repeated loss. 5. Maternal immune tolerance (which rejects fetal implantation) is a rare cause. blood tests can identify this problem. 5. In your case, this could be either due to progesterone deficiency during luteal phase or chromosomal abnormality. Progesterone is necessary for the continuation of pregnancy & a deficiency of progesterone in late luteal phase (period just after conception) can result in repeated loss of fetus. Chromosomal abnormality of either one of the partner results in miscarriages in the first 13 weeks. Karyogram detects chromosomal abnormality & blood tests & endometrial biopsy will reveal if the problem is due to Progesterone.