Estrogen breakthrough bleeding occurs when excess estrogen stimulates the endometrium to proliferate in an undifferentiated manner. With insufficient progesterone to provide structural support, portions of the endometrial lining slough at irregular intervals.
Bleeding can occur due to HRT if there is too much oestrogen or too little progestogen. Other causes of bleeding can be: Poor absorption: due to bowel disorders such as Crohn's disease, lactose intolerance, patches falling off.
Estrogens can be administered orally, such as conjugated estrogens, using dosages of 1.25 to 5 mg every six hours for a 12- to 24-hour period. Alternatively, intravenous estrogens at dosages of 20 to 25 mg can be administered every four to six hours to control heavy bleeding.
Bleeding on hormone therapy is very common within the first three months of treatment, but if there is ongoing bleeding, medical advice should be sought.
When your period first starts the blood is bright red in appearance, but later in the cycle the color shifts to a dark red. This change in color is completely normal and accompanies rising estrogen levels in your blood.
The blood is usually either light red or dark reddish brown, much like the blood at the beginning or end of a period. However, depending on the cause, it may resemble regular menstrual blood.
Starting and stopping HRT
It's common to have some vaginal bleeding in the first 3 months (for women who have a womb). If you have any unexpected bleeding in the first 3 months, tell your GP at your first review appointment. If it happens after the first 3 months tell your GP straightaway.
Bleeding between periods often happens when you start to take hormonal contraceptives. This is because your hormone levels drop. It is also called breakthrough bleeding, and usually happens about 2 weeks after your last period. Breakthrough bleeding should stop after 1 or 2 months.
After menopause, the uterine lining may become too thin. This can happen when a woman has low levels of estrogen. The condition is called endometrial atrophy. As the lining thins, a woman may have abnormal bleeding.
Sequential HRT – Oestrogen is taken every day, and the progestogen is taken for (usually) half of the month. HRT taken this way results in a monthly bleed. Continuous combined HRT – So-called because the two hormones (oestrogen and progestogen) are taken together, daily. This approach results in no bleeding.
Estrogen helps protect the heart from disease, potentially by maintaining higher levels of good cholesterol, called high-density lipoprotein (HDL), in your blood. Lower estrogen levels, especially during menopause, can increase your risk of developing heart disease.
Your body needs estrogen for your reproductive, cardiovascular and bone health. Too much estrogen, though, can cause irregular periods and may worsen conditions that affect your reproductive health. Your provider can help diagnose what's causing your high estrogen levels and recommend treatments that can help.
Secondary sexual characteristics, such as pubic and armpit hair, also start to grow when estrogen levels rise. Many organ systems, including the musculoskeletal and cardiovascular systems, and the brain are affected by estrogen.
'The colour of your menstrual blood can vary from bright red to dark brown or even black. The colour changes depending on how long the blood takes to leave your body,' says Dr Rosén.
During menstruation, the body sheds tissue and blood from the uterus through the vagina. This bloody discharge can vary from bright red to dark brown or black depending on how old it is. Blood that stays in the uterus long enough will react with oxygen (oxidize). Blood that has had time to oxidize appears darker.
What causes abnormal uterine bleeding? In many women, a hormone imbalance causes bleeding. These women may have too much estrogen or not enough progesterone. Polyps or fibroids (small and large growths) in the uterus can also cause bleeding.
However, you should consult your doctor if you get heavy (rather than light) bleeding, if it lasts for more than six months, or if bleeding starts suddenly after some time without bleeding. Irregular bleeding may sometimes be improved by changing the type or route of HRT.
When women take hormone replacement, the chance of bleeding episodes increases. Nature provided for a monthly event, called menstruation (a period) in order to prevent an abnormal accumulation of tissue in the uterus. Woman who are on hormone replacement usually receive estrogen and progesterone.
Menopause hormone therapy can result in light bleeding or bleeding that's as heavy as a normal period. If your bleeding concerns you, see your doctor.
Endometriosis can also cause a person to have spotting. Spotting is when a person bleeds in small amounts between periods. Blood that occurs due to spotting may be red, pink, or brown.
Most people notice spotting as a few drops of blood on their underwear or toilet paper when wiping. In most cases, spotting should not cause concern. Often, hormonal changes due to birth control, pregnancy, or menopause can trigger it.