Could Clomid cause a pregnancy loss?
It's really hard for me to blame Clomid for pregnancy loss because, normally, Clomid is given to people only whose ovaries aren't functioning perfectly normally to begin with. Or it's given to people "empirically", without a clear diagnosis, but in the hope that, whatever the problem truly is, Clomid can help! When things go wrong, chances are great that the problems had nothing to do with the Clomid. However, there have recently been some reports of paradoxical responses to Clomid that cause the uterine lining to be thinned. This can be measured by ultrasound in the second half of your cycle. I've read reports that baby aspirin treatment may improve the thickness of thin uterine linings. Clomid can indirectly raise your risk of miscarriage because it causes you to ovulate more eggs than you normally would, possibly including imperfect eggs that your body might normally censor. Since there is a greater likelihood of ovulating eggs that are defective (along with the healthy ones) there is a greater risk of miscarrying. The imperfect eggs are what might cause the pregnancy loss.
Clomid works by affecting the hormonal chain reactions that regulate the process of ovulation. At the start of each menstrual cycle, the hypothalamus (a gland in the brain) sends gonadotrophin-releasing hormone (GnRH) to the pituitary gland at the base of the brain. The pituitary then releases another hormone--follicle-stimulating hormone (FSH)--that signals your ovaries to step up their production of the hormone estrogen. Clomid binds to receptors in the brain so that your brain can't perceive that your ovaries are making estrogen. Because your brain thinks your ovaries aren't making estrogen, it continues making more follicle stimulating hormone (FSH). The FSH signals your ovaries to step up the production of more estrogen, causing your estrogen levels to rise higher than they normally would and to remain high for longer than usual. Higher estrogen levels for a longer period of time will cause more eggs to be ovulated with no guarantee that those eggs are viable.
