Exactly the opposite actually!When you do miss two periods, does the buildup of uterine lining accumulate to 2-3 months worth, making the periods you do get abnormally heavy?
I think its important to quickly review the way combined oral contraceptives (estrogen and progestin) work to suppress pregnancy.
The role of continuous estrogen is to prevent ovulation. By providing a steady state of estrogen, the body is actually tricked into thinking it is pregnant and so the complex cycle of hormones is temporarily shut down. This means no eggs mature or are released while on the OCP. And you can't get preggers!
The role of progestin is 3-fold:
- It alters cervical mucous, making it harder for sperm to enter into the uterus
- It somehow alters the natural movements of the fallopian tubes which bring eggs to the uterus (if they are released),
- and lastly, it prevents the uterine lining from building up to any appreciable level which would allow for egg implantation (again, if somehowm they are released).
This last point is the real reason for breakthrough bleeding while on the pill: your uterine lining is actually thin and fragile, which may allow small blood vessels to break and bleed. This is more so the case with lower estrogen preparations (like the ring), as estrogen stabilizies the uterine lining.
After doing back to back pills/patch/ring, your preiod should be no more heavy than it has been previously. It may just seem that way since you havent menstruated in months!