Is the miscarriage rate higher in women with PCOS?
There does appear to be a higher miscarriage rate in women with PCOS, but the exact reason is still under investigation. According to some studies, the risk of miscarriage in women with PCOS is 45 percent or more. One possibility is that early loss is associated with elevated levels of luteinizing hormone — and women with PCOS often have elevated LH levels — but the reason why it relates to miscarriage is not understood. Another possibility is that elevated levels of insulin or glucose may impede implantation or cause problems with the embryonic development. There is a clear association between uncontrolled blood sugar and pregnancy loss, but the issue of insulin resistance and elevated insulin levels is relatively new and in need of further study. There is a possibility that insulin resistance reduces egg quality. That leads to another possibility — that late ovulation (after cycle day 16) may be associated with poor follicle development and decreased egg quality.
Is there anything that can be done to reduce the chance of miscarriage in a woman with PCOS?
The primary way to reduce miscarriage associated with PCOS is to normalize hormone levels. For women with low progesterone levels in the luteal phase, improving ovulation through the use of clomiphene citrate, or injectable FSH or FSH/LH may help the problem. Addressing ovulation issues is more useful than progesterone supplementation as low progesterone is usually a symptom of a problem, such a weak ovulation, rather than the actual cause of miscarriage. Normalizing blood sugar and glucose levels may help, and lead to lower androgen levels, so use of metformin (see next question) during pregnancy is increasing. Most doctors would have patients discontinue use of the glitazones.
Can metformin reduce the chance of miscarriage?
It appears that continuing metformin use at least through early pregnancy may reduce the chance of miscarriage, especially in patients with recurrent losses. A recent abstract, "Metformin throughout pregnancy in women with polycystic ovary syndrome reduces first-trimester miscarriage" (CJ Glueck et al, J Invest Med 2000), revealed a group's experience with 59 pregnant PCOS women. Of these, 23 were kept on metformin for the long haul. The other 36 did not continue metformin in pregnancy. This is a very small sample, but the miscarriage rate was 45 percent without metformin and only nine percent with metformin. Chi-square testing showed these rates to be highly significant from a statistical point of view, but their true clinical impact must await further prospective studies. As with any medication used in pregnancy, doctor and patient must assess whether the benefit outweighs any potential risk.
Does having PCOS make pregnancy high risk?
The answer to this may depend a little on the definition of high risk. Most PCOS patients can see a regular OBGYN, or perinatologist. Anyone who is severely insulin resistant, diabetic, or has high blood pressure may need to see a high-risk OBGYN. This is an issue to be decided by doctor and patient together.
Does a pregnant woman with PCOS require special monitoring?
Some special monitoring may make sense — such as earlier gestational diabetes screening or home glucose monitoring. Beyond that it depends on the PCOS symptoms experienced by the patient before pregnancy. Anyone taking medication may require additional monitoring. Many of the issues one needs to watch for are included in routine pregnancy care. For example, a woman with borderline hypertension before is more likely to have increased blood pressure in pregnancy, but most doctors check all patients for blood pressure issues.
Is low-carbohydrate dieting healthy in pregnancy?
A diet that is very low in carbohydrates is not safe during pregnancy. If the body is too low on resources, it will burn fat for calories. A byproduct of this is ketones, and these may not be healthy for the growing fetus. It is best to follow a meal plan that allows consumption of vegetables and complex carbohydrates at each meal and snack. A couple of the plans listed in the weight section are safe during pregnancy, and consultation with a nutritionist familiar with gestational diabetes may help.
Can insulin-sensitizing medications such as metformin and the glitazones be taken during pregnancy?
It has been recognized for years that high glucose levels can have a detrimental effect on the growing fetus and most doctors would suggest diet and/or insulin injections to control this, but recently there has been discussion that high insulin levels may be just as damaging.
Continuing metformin in pregnancy is an area of controversy — some doctors won't prescribe it to women who are trying to conceive, some tell patients to discontinue metformin after a positive pregnancy test, some wait for a heartbeat, some treat through the first trimester, and others continue the medication throughout the pregnancy. There are some studies that indicate continuing the medication may reduce the risk of miscarriage. The long-term risks to the baby are not known, but many apparently healthy babies have been born to women who used metformin while pregnant. Metformin is a Pregnancy Category B drug, meaning that it has not been known to cause birth defects in rats, but there are no adequate studies in pregnant women and the choice to continue metformin should be based on whether one considers the potential benefits to outweigh the risks. This is an area where a woman and her doctor have to weigh the risks and benefits together.
As for the glitazones, Avandia and Actos are considered safe to the patient using them, but both are listed as Pregnancy Category C medications. Most doctors will ask patients to discontinue use of these medications during pregnancy.
