Menstrual Cycle, Luteinizing Hormone and Superfetation
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Bleeding occurs in around 20% of normal pregnancies ranging from a one-time occurrence, to period like bleeding every month. However, during a cryptic pregnancy it is much more common to have continued menstrual cycles. In fact it is one of the most commonly shared symptom among cryptic pregnancies aside from undetectable HCG. Those cycles typically change to about half of the normal length, and much lighter in flow. So if the woman is used to a 5 to 7 day cycle, she will begin experiencing a 1 to 3 day cycle. There is a very wide variety of the way these cycles will present themselves. They may come like clockwork every month or they may be sporadic. Some women may experience nonstop spotting and bleeding for weeks at a time or the woman may bleed only a few times throughout the pregnancy. They can range from heavy, medium, light, or spotting. The menstrual bleeding may be bright red, pink, orange, brown, purple or black. It may have a mucus like texture. There may be small chunks, large chunks, or no chunks at all. It can be thick or thin and watery. There may be heavy painful cramping or none at all. In short, there will usually be some sort of noticeable change in the menstrual cycle. This may be very difficult to see in women that have PCOS or other hormonal imbalances before becoming pregnant because often their cycles are already erratic.
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In a typical pregnancy, certain hormones are not produced such as the luteinizing hormone, because of the increased production of hormones such as HCG, estrogen and progesterone. LH is the hormone responsible for triggering ovulation and for thickening the uterine lining. When a woman is not pregnant, or pregnant but not producing HCG, the luteinizing hormone level drops which triggers the shedding of the uterine lining. In a typical pregnancy HCG-a mimics the luteinizing hormone and tells the woman’s body not to shed the lining. Since the HCG keeps the cycle from ending in a period, the body doesn’t go through another cycle with ovulation again. However, that is not the case with cryptic pregnancy due to the lack of HCG and the normal levels of estrogen, progesterone and prolactin in the woman’s system. The woman’s body may continue to go through a normal cycle including ovulation. There is a rare pregnancy that happens when a woman gets pregnant again while being pregnant already. It is called superfetation. The chances of that are extremely rare, happening in one woman a year for the entire world (an estimation which I believe to be wrongly stated due to undocumented cases of normal pregnancies that happen on top of cryptic pregnancies). When this type of pregnancy happens, it usually happens because the first pregnancy was a cryptic pregnancy.
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