It has been proved that ladies with PCOS are more likely to miscarry. The figures show about 1 in 4 pregnancies end in MC but is almost 1 in 2 with PCOS.
Taken from a PCOS website...
" LH (luteinizing hormone) hypersecretion. Some women with PCOS have elevated LH during the follicular phase (first half of the cycle), which prematurely sends a signal to the egg that it is about to be released from its follicle. The egg then prematurely disconnects from its supporting cumulus cells, which causes the egg to pause in its maturation process.
It is thought that this interruption in the normal maturation process may result in abnormal chromosomes in the egg, which would then substantially increase the probability of a miscarriage.
Other Hormones. Of course, other hormonal imbalances besides FSH and LH may be involved.
Women who miscarry appear to have higher levels of testosterone and DHEA than women with continuing pregnancies.
Women who miscarry may tend to have higher prolactin and androgen levels during the follicular phase of their menstrual cycle.
Insulin and insulin resistance. Some women with polycystic ovarian syndrome have insulin resistance, where an excessive amount of insulin is required to control blood sugar levels. High insulin levels stimulates further production of LH and testosterone. Excessive levels of insulin, LH and testosterone are associated with poorer egg quality, thus increasing the risk of miscarriage. Insulin resistance has been linked to recurrent pregnancy loss. "
Metformin has been used in lots of ladies I know who have had MCs