Clomid (Clomiphene Citrate)
To understand why Clomid increases your chances of having twins, it is helpful to know how clomid works. Clomid works by blocking estrogen receptors in your brain. Estrogen is one hormone involved in the ovulation process. During the first part of your menstrual cycle, your estrogen levels are low (during menses). Normally, eggs begin to mature during this time and when this happens they produce estrogen. Estrogen levels increase as the eggs mature and eventually your estrogen levels reach a point that signals your body to produce another hormone known as LH. A surge in LH is what ultimately triggers ovulation.
Clomid is similar to estrogen in its make-up. It is a SERM (selective estrogen-receptor modulator). The receptor cells in your brain think that Clomid is estrogen which allows the Clomid to attach to the receptor cells. When Clomid attaches to the receptor cells, it keeps your own estrogen from attaching to the cells. This causes your body to think that you are not making enough estrogen. When estrogen levels are low, your body responds by making other hormones that help nurture and mature the follicles that are growing in your ovaries. Why you might ask? Because the follicles are what produce estrogen and your body wants your estrogen levels to increase. Your body thinks your follicles are not producing enough estrogen so it starts producing more of the hormones that help the follicles mature so that they will start producing more estrogen. Its a cycle.
The reason that Clomid increases your chances of having twins is fairly easy to understand. Your body is producing extra hormones to help your follicles grow and mature, thus increasing your estrogen levels. When this happens, a woman may have so much extra stimulation and nurturing that she produces more than one mature egg. If more than one egg is released during ovulation and both eggs are fertilized, twins will result. In most cases, Clomid twins are fraternal because they are the result of two different eggs.
What are the chances of having twins while taking Clomid?
You have about a 1-3 percent chance of conceiving twins naturally. Clomid does increase your chances of having twins, but not as much as you might think. You have about an 10-12% chance of conceiving twins while taking Clomid. For couples that have faced infertility though, the increased chance of having twins might not be a huge concern; actually, they might even see it as an added bonus.
Soy Isoflavones (SI)
What makes soy isoflavones similar to Clomid
Soy isoflavones are phytoestrogens known as SERMs, or Selective Estrogen Receptor Modulators. Clomid is also a SERM. Some people believe that soy isoflavones function in the same way to block estrogen receptors as Clomid.
Researchers have found that soy isoflavones bind to estrogen receptors. This evidence may support the idea that soy isoflavones can work as a natural ovulation inducer like Clomid.