Oral contraceptive pills (OC pills) are a safe and reliable option for preventing unwanted pregnancy. It is used by almost 16% females aged 16-45 years in the US. Despite being safe and effective, even the best contraceptive pills have side effects. As various contraceptive pills have different combinations of hormones, a type of pill suitable for one female can cause side effects in others.
What are the types of oral contraceptive pills?
OC pills constitute of synthetic human hormones—estrogen and progesterone, and how to use a contraceptive pill depends on its type. Based on the type of hormones a pill has, it is classified as follows:
Combined contraceptive pills: This type of pill has both the hormones, estrogen and progestin. There are various types of contraceptive pills available:
- Monophasic pills: These are used for the monthly cycle and each pill has the same hormonal dose. Active pills are taken for 21 days, followed by inactive pills for 7 days when menstruation occurs.
- Multiphasic pills: These are used in a similar fashion to that of monophasic pills. However, these pills provide different doses of hormones during the cycle.
- Extended-cycle pills: These are typically used in a 13-week cycle. Out of which, active pills are taken for 12 weeks and inactive pills during the last week, when menstruation occurs. Thus, a female on these pills gets periods only 3-4 times in a year.
Progestin-only pill: It contains only progestin without estrogen and is a good choice in a female who cannot take estrogen, like a female suffering from a estrogen secreting tumor.
How does contraceptive pills work?
OC pills are made up of synthetic female hormones, progesterone and estrogen, which are naturally present in the body. These synthetic hormones impede the functioning of the natural hormones in the body. They prevent pregnancy by the following mechanisms:
- Preventing or delaying ovulation
- Thinning the uterine lining and inhibiting implantation
- Thickening the cervical mucus that prevents entry of sperms in the reproductive tract, hindering fertilization
Side effects of contraceptive pills
Common side effects
- Spotting in between periods: It is seen in 20–30% of the females on OC pills
- Amenorrhea: Absence of menses is observed in 2–3% of the females
- Weight gain: 22.35% of females on OC pills experience weight gain. Estrogen contributes to this transient weight gain as it causes sodium and water retention. Progesterone can also cause weight gain due to the anabolic effect.
- Gastralgia: It is reported by 14.8% females on OC pills.
- Acne and nausea: These symptoms are experienced by 7.4% females on OC pills.
- Vertigo: Only 3.7% females on OC pills report vertigo as a side effect.
Serious side effects
- Blood clots: Both, combined and progestin-only pill, increases the risk of blood clots, predisposing an individual to a stroke or a heart attack.
- Cancer: According to the American Cancer Society (ACS), females on contraceptive pills are marginally at a higher risk of developing breast cancer as compared to females who have never consumed them. The ACS also reports that consuming these pills for more than 5 years raises the risk of cervical cancer.
- Others: other serious side effects are blurred vision, severe stomach ache, and severe headache.
Oral contraceptive pills are a relatively safe option of contraception and are the best contraceptive pills as they are almost 100% effective. However, some females can face a few side-effects, and hence consulting a doctor before starting them is recommended.